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Pipette

A pipette is a laboratory instrument commonly used in chemistry, biology, and medicine to measure and transfer precise volumes of liquid, often in small quantities ranging from microliters to milliliters. These tools are essential for accurate experimental procedures, sample preparation, and diagnostic testing, where even minor volume errors can affect results. Pipettes operate on principles such as , where a creates to draw into a disposable tip, or positive for viscous or volatile fluids, minimizing and ensuring . Common types include volumetric pipettes, which deliver a single fixed volume with high accuracy for critical measurements; graduated or serological pipettes, marked with increments for variable volumes greater than 1 ml; transfer or Pasteur pipettes, simple disposable glass or plastic tubes for rough transfers or drops; and micropipettes, adjustable devices for microliter-scale work using specialized tips. They are calibrated as "to deliver" (TD) for dispensing exact amounts or "to contain" () for holding volumes, with some requiring a blow-out step to expel residual . The history of pipettes dates back over 200 years to simple glass tubes filled by suction, evolving in the with the Pasteur pipette for sterile transfers in . The modern micropipette was invented in 1957 by Heinrich Schnitger at the , , featuring a spring-loaded and disposable plastic tip to replace hazardous pipetting and enable precise microliter handling. Commercialized by Eppendorf in the , this innovation transformed biological and medical research by enabling precise handling in techniques such as preparation, , and high-throughput assays. Today, electronic and multichannel variants further enhance efficiency in automated workflows.

Overview

Definition and Purpose

A pipette is a laboratory instrument designed to transport a measured volume of , typically ranging from microliters to milliliters, ensuring high accuracy in experimental procedures. This device is indispensable for precise handling, where even minor volume discrepancies can compromise results in scientific research. The primary purposes of pipettes include accurate dosing and transfer of liquids in various scientific disciplines, such as for preparing analytical solutions and titrations, for molecular techniques like () and maintenance, and medicine for clinical examinations and pharmaceutical formulations. In these applications, pipettes enable reproducible outcomes by minimizing contamination risks and supporting sterile environments, particularly in and diagnostics. Key characteristics of pipettes encompass their construction materials, which include chemically inert for durability and plastic for disposable, sterile use; volume capacities spanning 0.1 μL to 100 mL to accommodate diverse experimental needs; and precision classifications such as Class A for high-accuracy applications and Class B for general tasks. Over time, pipettes have evolved from simple tubes to advanced models, enhancing efficiency while maintaining core principles of precision.

Basic Principles of Operation

Pipettes operate primarily through two displacement principles: air displacement and positive displacement, each suited to different properties for maintaining accuracy in volume transfer. In the air displacement principle, a within the pipette displaces air to create a partial , drawing the liquid into a disposable tip without direct contact between the instrument and the sample. This method relies on an air cushion between the piston and the liquid, ensuring precise for low-viscosity, aqueous solutions where allows reliable aspiration and dispensing. Common in air displacement micropipettes, it minimizes risks by isolating the liquid in the tip. The positive displacement principle employs a piston integrated into the disposable tip that directly contacts the liquid, eliminating any air interface and ensuring complete expulsion through a wiping action on the upstroke. This design prevents leakage or retention, making it ideal for viscous liquids that resist flow or volatile substances prone to evaporation during handling. By maintaining consistent force regardless of liquid properties, it achieves high accuracy in challenging samples. Several factors influence pipette accuracy beyond the displacement mechanism. Evaporation, particularly in volatile liquids, can reduce the dispensed volume if not mitigated by rapid operation or positive displacement systems. Temperature variations affect liquid density and pipette material expansion; a density correction Z-factor accounts for this, approximately Z \approx 1 + \alpha \times \Delta T (where α is the thermal expansion coefficient of water, ≈ 2.1 × 10^{-4} /°C, and ΔT is the temperature deviation from the reference of 20°C), but is typically obtained from tabulated values based on temperature and pressure per standards like ISO 8655, ensuring volume calculations reflect true density changes. Air buoyancy requires correction during gravimetric verification, as the density of surrounding air displaces the measured mass, typically by a factor derived from ambient pressure and temperature. Meniscus formation at the liquid-air interface in the tip or vessel can introduce reading errors if not viewed at eye level or if immersion depth is improper, leading to over- or under-aspiration. Standard operation involves three key steps to ensure contamination-free transfer. begins by immersing the 2–3 mm into the and slowly releasing the from the first stop position to draw the sample without bubbles. Dispensing follows by positioning the against the wall and pressing the to the second stop for complete ejection, including any residual . ejection removes the used via a dedicated , preventing cross-contamination in subsequent uses.

History

Early Developments

In the pre-19th century era, rudimentary glass tubes served as basic tools for liquid transfer in early chemical practices, relying on and manual suction to move small volumes between vessels. These simple implements, often crafted by glassblowers for alchemical and rudimentary experimental work, lacked precision but laid the groundwork for more refined apparatus. During the 19th century, significant advancements emerged in pipette design, particularly for microbiological applications. French chemist and microbiologist (1822–1895) is credited with developing the first practical glass Pasteur pipettes, which consisted of tapered tubes often plugged with to filter air while transferring sterile liquids, revolutionizing sample handling in his germ theory experiments. In 1877, British surgeon used a specialized glass micro-pipette to dispense precise drops of diluted bacterial solutions in his experiments demonstrating pure bacterial cultures, avoiding direct oral contact through careful handling. In the early , pipettes evolved toward greater accuracy in with the introduction of volumetric pipettes, calibrated for delivering precise fixed volumes, often using like for thermal stability. Complementing these, graduated pipettes incorporated etched markings along the tube for variable volume measurements, exemplified by designs such as the Carlsberg pipette, which featured a pulled tip for microliter-scale work. These developments shifted pipetting from qualitative transfer to . A pivotal milestone occurred in 1957 when German physician Heinrich Schnitger at the created the first piston-driven micropipette prototype, incorporating a spring-loaded and disposable tip to achieve microliter precision while eliminating the risks of mouth pipetting. Eppendorf commercialized an adjustable version of this design in 1961, making it widely available to researchers. This manual device marked a transition toward safer, more ergonomic tools that paved the way for adjustable models in subsequent decades.

Modern Advancements

In the 1970s, the development of the first commercial adjustable micropipette marked a pivotal advancement in precision liquid handling. Warren Gilson and Henry Lardy at the invented the air displacement micropipette, commercialized as the Gilson Pipetman in 1972, which allowed users to set and dispense variable volumes accurately without direct contact between the pipette and the liquid, significantly reducing contamination risks and improving reproducibility in laboratory workflows. This innovation revolutionized microliter-scale pipetting, enabling faster and more reliable experiments in fields like biochemistry and . During the and , pipette technology shifted toward enhanced sterility and efficiency through the widespread adoption of disposable tips, which minimized cross-contamination compared to reusable alternatives. This transition supported the rise of multi-channel pipettes, first patented by Osmo Suovaniemi and developed into models like the Finnpipette Multichannel, allowing simultaneous dispensing from 8 or 12 channels to accelerate in and . By the , these multi-channel designs had become standard in automated workflows, boosting productivity in large-scale assays while maintaining sub-microliter accuracy. The 2010s introduced electronic pipettes with digital displays and programmable functions, further refining user control and reducing manual errors through motorized plunger operation and volume presets. Models like those from Eppendorf and Rainin integrated screens for real-time feedback, enabling modes such as serial dilutions and mixing with precision up to ±0.5% accuracy across volumes from 0.1 μL to 10 mL. integration emerged in the 2020s, exemplified by the Thermo Scientific E1-ClipTip series, which connects to cloud-based apps like My Pipette Creator for wireless data logging, protocol sharing, and compliance tracking in regulated environments. Recent developments from 2024 to 2025 have incorporated AI-driven features for predictive error detection in automated systems, using to analyze pipetting parameters in and flag anomalies like volume discrepancies with over 95% accuracy. Contactless dispensing technologies, such as the Dispendix I. platform, enable non-invasive nanoliter transfers without tips, reducing waste and contamination in high-throughput applications like . Additionally, manufacturers like GenFollower Biotech introduced 5 mL large-volume pipette tips in 2024, featuring enhanced optical clarity for better visualization during viscous liquid handling in research.

Nomenclature and Classification

Terminology

In laboratory contexts, the term "pipette" is the preferred spelling in , while "pipet" is more commonly used in , with both referring to the same device for precise liquid transfer and no difference in meaning. A specifically denotes a pipette designed for volumes less than 1000 μL, enabling accurate handling of small liquid quantities in applications like . Serological pipettes are graduated instruments primarily used in workflows to measure and dispense milliliter-scale volumes of media or reagents. Key measurement terms distinguish pipette calibration and performance: "TD" (to deliver) indicates calibration where the pipette is designed to dispense the nominal volume, with subtypes varying on blow-out—standard volumetric (TD) account for residual in calibration and do not require blow-out, while many graduated and serological are TD but marked for blow-out (e.g., with two rings) to deliver the full ; "TC" (to contain) means the pipette holds the specified when filled to the mark, requiring blow-out for full delivery, common in types. Nominal represents the maximum capacity marked on the pipette, serving as the reference for its intended use range. Accuracy measures the closeness of dispensed to the nominal value, expressed as percentage error; quantifies reproducibility across multiple dispenses, typically as (CV%), calculated from the deviation relative to the mean. Nomenclature for piston-operated volumetric apparatus, including air-displacement , follows ISO 8655 standards, which define terminology, metrological requirements, and testing for devices like and dispensers to ensure and reliability. For , Class A denotes higher with tighter tolerances (e.g., ±0.2% for volumes over 5 mL), suitable for analytical work, while Class B offers with approximately double the tolerance, for general use. Common abbreviations include μL for microliter (10^{-6} L) and for milliliter (10^{-3} L), for pipette volumes. "Blow-out" refers to the forced expulsion of residual from the pipette to achieve complete , required for TC-calibrated devices and blow-out-marked TD types such as certain serological pipettes.

Types Overview

Pipettes are broadly classified by their operational mechanism into manual and types. Manual pipettes rely on user-applied force via a or for and dispensing, offering simplicity and cost-effectiveness for routine tasks. In contrast, pipettes incorporate battery-powered motors to automate movement, enhancing , , and while reducing physical strain on users during high-throughput applications. Material composition further delineates pipette categories, with and variants serving distinct needs. pipettes, typically made from borosilicate, provide durability and chemical resistance for reusable applications involving harsh solvents. pipettes, often constructed from or , are disposable or semi-disposable, minimizing cross-contamination risks in sterile environments like labs. Volume adjustability splits pipettes into fixed and variable subtypes; fixed-volume models deliver a predetermined amount with minimal , ideal for repetitive assays, whereas variable-volume pipettes allow range adjustments from microliters to milliliters for versatile protocols. Displacement mechanisms classify pipettes as air displacement or positive displacement. Air displacement pipettes, the most common type, employ an air cushion between the piston and liquid sample to facilitate transfer, suitable for aqueous solutions with low viscosity. Positive displacement pipettes, however, use a direct piston-sample interface via disposable tips, ensuring accurate handling of viscous, volatile, or dense fluids without air interface complications. Scaling distinctions include volumetric pipettes, which measure a single precise volume for quantitative analysis, and graduated pipettes, marked with incremental divisions for variable measurements in qualitative or semi-quantitative work. Application domains guide pipette selection, with macro-scale devices handling volumes in milliliters or larger for fields like and clinical diagnostics, where bulk transfers are routine. Micro-scale pipettes target microliter ranges, essential for techniques such as and that demand high precision at low volumes. Specialized pipettes address niche needs, including those for gas analysis or cellular manipulation, adapting designs to handle non-liquid media or delicate biological entities. As of 2025, emerging categories in liquid handling emphasize and contactless technologies to boost and sterility. Automated pipettes, extending electronic models to multichannel and robotic integrations, streamline workflows in . Contactless systems, leveraging non-invasive dispensing methods like acoustic or piezoelectric ejection, minimize and enable in advanced assays.

Common Types of Pipettes

Volumetric and Graduated Pipettes

Volumetric pipettes are precision instruments designed to deliver a fixed of in a single, accurate dispensing operation. These pipettes feature a bulbous connected to a narrow , with a single etched mark indicating the exact , such as 10 mL or 20 mL. They are calibrated "to deliver" (TD), meaning the specified is achieved after allowing the to drain freely by , without blowing out the residual in the . This is performed at 20°C to account for the of the and . Class A volumetric pipettes, the for high-precision work, adhere to strict outlined in ASTM E969, ensuring minimal error; for instance, a 10 mL pipette has a maximum of ±0.02 mL. These pipettes are typically constructed from , valued for its thermal resistance, chemical inertness, and durability, which prevents leaching or distortion during repeated use. In applications, volumetric pipettes are essential for tasks requiring exact volumes, such as preparing solutions for titrations or performing dilutions in . However, they exhibit limitations with viscous liquids, as incomplete drainage can lead to volume inaccuracies exceeding the limits. Graduated pipettes, also known as measuring pipettes, enable the delivery of variable volumes up to a maximum capacity through etched graduation marks along the stem, allowing for flexible measurements in increments such as 0.1 mL on a 10 mL pipette. There are two primary subtypes: Mohr pipettes, where graduations terminate before the tapered tip and are calibrated without a blow-out feature, requiring users to leave the final drop in the tip; and serological pipettes, which extend graduations to the tip and include a blow-out bulb or mark, permitting complete expulsion of the liquid for total volume delivery. Like volumetric pipettes, Mohr types are often made of borosilicate glass for reusability and precision, while serological pipettes are commonly produced from disposable polystyrene plastic to minimize contamination risks in sterile environments. These graduated pipettes are widely used for approximate volume transfers in procedures like solution dilutions or in titrations, where exact single volumes are not required but controlled variability is needed. variants offer convenience for single-use applications, reducing cleaning needs and cross-contamination, though they may lack the longevity of . As with volumetric types, handling viscous liquids poses challenges, as to the inner walls can cause uneven and errors.

Air Displacement Micropipettes

Air displacement micropipettes function through a piston-cylinder system that creates an air cushion to aspirate and dispense microliter volumes of without direct contact between the mechanism and the sample. The device features a thumb-operated that moves within the , displacing air to draw liquid into a detachable tip; upon dispensing, the reverses to expel the air, forcing the liquid out. This air-cushion ensures of the internal components from potentially corrosive or contaminating liquids, making it for aqueous solutions in biological and chemical laboratories. Models are available in single-channel configurations for volumes ranging from 0.1 to 1000 μL, while multi-channel versions with 8 or 12 parallel tips facilitate high-throughput processing of microplates, such as 96-well formats. Electronic variants of air displacement micropipettes employ motorized pistons for automated control, allowing programmable speeds for and dispensing to optimize across diverse viscosities and reduce variability. Systems like the Eppendorf epMotion series (introduced in 2003, with subsequent updates including a new generation in 2023), integrate these motorized air-cushion tools into compact workstations for tasks including and serial dilutions, supporting up to 15 worktable positions for complex workflows. By minimizing the physical force required from the operator compared to models, electronic pipettes help alleviate risks associated with prolonged laboratory use. These micropipettes achieve high accuracy, typically within ±1% at nominal volumes such as 10 μL, when operated near their full and with proper technique, though diminishes below 50% of the maximum volume. Low-retention , designed with hydrophobic surfaces, enhance performance for sticky or viscous samples by reducing and preventing residue retention, thereby maintaining reliability. For highly volatile or dense , positive alternatives may be considered to avoid air cushion inconsistencies. In applications like quantitative polymerase chain reaction (qPCR) and enzyme-linked immunosorbent assays (), air displacement micropipettes enable precise reagent addition to microplates, supporting reproducible results in and immunoassays. As of 2025, emerging trends feature Bluetooth-enabled electronic models that provide connectivity for real-time pipetting data tracking and integration with laboratory information management systems, improving and in regulated environments.

Positive Displacement Pipettes

Positive displacement pipettes function through a mechanism where the piston directly contacts and displaces the liquid sample, eliminating the air gap or cushion found in other pipette types. This is achieved using a disposable capillary piston integrated into a specialized tip, which creates a direct seal with the sample and allows precise volume control via the piston's movement. The process involves immersing the tip slightly into the liquid and pressing the plunger to the first stop to draw the sample directly into the capillary without introducing air; dispensing occurs by pressing the plunger to the first stop, forcing the liquid out directly. This direct-contact approach prevents aerosol formation, making it especially suitable for volatile liquids like ethanol, where evaporation or contamination risks are high. These pipettes are available in both manual and designs, with examples including the Gilson E for electronic operation and manual models like the Eppendorf Multipette series. Volume ranges typically span from 0.5 μL to 5000 μL, accommodating a variety of applications while maintaining compatibility with specific disposable tips that incorporate the capillary piston. The design ensures that the pipette body remains uncontaminated, as the disposable components handle all interaction. The primary advantages of positive displacement pipettes lie in their ability to handle challenging liquids, such as viscous substances like oils and , foaming solutions, or high-density fluids, without loss of accuracy or precision. By avoiding air cushion effects, they deliver consistent volumes unaffected by factors like , , or variations, with systematic errors as low as 0%–1% for and 0.1% for acetone. This contrasts with air displacement pipettes, which perform well for routine aqueous samples but can introduce errors with non-standard liquids. Additionally, the direct displacement reduces cross-contamination risks and protects both the user and the instrument from hazardous or infectious materials. Despite these benefits, positive displacement pipettes have limitations, including a potential for tip clogging when dealing with or highly viscous samples, which may require careful wiping of the tip exterior with lint-free materials. They also necessitate the use of proprietary tips with built-in pistons, which are not interchangeable with standard tips and can increase operational costs. Dispensing accuracy relies heavily on the quality of these disposable components, emphasizing the need for high-quality, compatible supplies.

Pasteur and Transfer Pipettes

Pasteur pipettes are long, thin tubes typically constructed from glass or plastic, with capacities ranging from 1 to 3 , designed for the and transfer of small liquid volumes using mouth or a rubber bulb. These pipettes were developed in the mid-19th century by , who utilized simple drawn-glass tubes to handle liquids in his experiments on and germ theory. Glass versions offer reusability after sterilization, while plastic variants, often made from (LDPE), provide flexibility and disposability to minimize contamination risks. Transfer pipettes, sometimes referred to in the context of serological applications, are shorter plastic devices equipped with an integrated or accessory , accommodating volumes from to 50 mL, and are commonly sterilized for use in and biological handling. These , primarily made from LDPE for its pliability and chemical resistance, facilitate quick and dispensing without the need for precise . They are ideal for non-critical liquid transfers, such as dispensing or aliquoting samples in routine workflows where accuracy is secondary to efficiency and sterility. Unlike graduated versions used for volumetric measurements, these ungraduated tools prioritize simplicity and speed in approximate operations.

Specialized Types of Pipettes

Gas Analysis and Syringe Pipettes

Gas analysis pipettes and syringe-based designs are specialized tools in , engineered for precise handling and measurement of gases or gas-evolving reactions, particularly in scenarios involving , , or gaseous mixtures. These instruments facilitate accurate volumetric determinations under controlled conditions, often integrating features like or combustion chambers to isolate and quantify gases such as CO2, , and N2. Unlike standard liquid transfer pipettes, they address challenges posed by gas , , and reactivity, ensuring minimal loss or during . Pipetting syringes, also known as repeating or syringes, feature a mechanism with an integrated system that enables repeated dispensing of precise volumes from a single . These devices, typically ranging from 0.025 to 50 , use a self-refilling with Luer Lock connections for with various , allowing for efficient delivery of liquids that may gases or require gas-tight sealing. They operate on a positive principle, where the directly contacts the sample to prevent air gaps, making them suitable for viscous or volatile substances in gas-related assays. The Van Slyke pipette, developed around 1917, is a manometric apparatus pivotal for blood gas analysis, enabling the extraction and measurement of dissolved CO2 and N2 volumes through and absorption techniques. Invented by Donald D. Van Slyke and J.M. Neill, it involves sealing a blood sample in a chamber, applying vacuum to liberate gases, and using chemical absorbers to quantify individual components via pressure changes, with high accuracy, typically achieving errors less than 1% for the gases determined. This design revolutionized quantitative gasometry by providing a direct method for assessing gas tensions in physiological fluids. Ostwald-Folin pipettes, originating in the early 1900s, consist of a wide-bulb configuration near the tip to accommodate viscous fluids like or , facilitating accurate transfer and measurement without clogging. Named after and refined by Otto Folin, these volumetric pipettes deliver fixed volumes (e.g., 0.01 to 2 mL) and are calibrated for serous or hematic samples, where the bulb's expanded shape reduces effects and improves drainage for reliable gas evolution studies. Their robust glass construction ensures durability in repeated use for clinical assays. The Winkler-Dennis pipette is a combustion-based device for determining oxygen content in gaseous mixtures or evolved gases from water samples, employing a platinum spiral to ignite combustibles under reduced pressure. Developed as a modification of earlier Hempel designs, it combusts the sample gas in a sealed chamber, absorbing the resulting products to measure residuals via , particularly useful for oxygen detection in environmental or gases. This pipette's integrated setup minimizes errors from incomplete reactions, achieving precise quantification in low-oxygen scenarios. These pipettes find essential applications in respiratory , where tools like the Van Slyke apparatus enable detailed profiling of blood gas exchanges to evaluate lung function and acid-base balance. In environmental testing, devices such as the Winkler-Dennis facilitate oxygen assessments in aquatic systems, supporting monitoring by quantifying dissolved oxygen levels critical for .

Microinjection and Microfluidic Pipettes

Glass micropipettes are fine-tipped glass , typically pulled from borosilicate tubing with outer diameters of 1.0-1.2 mm, resulting in tip inner diameters ranging from 0.5 to 10 μm for precise into cells or embryos. These pipettes are fabricated using a micropipette puller that heats and elongates the under controlled conditions to form the tapered , enabling penetration of cellular membranes without significant damage. Microfluidic pipettes represent an advancement in the , featuring chip-based designs with integrated microchannels for automated dispensing of nanoliter volumes, often incorporating droplet generation or programmable ejection mechanisms. These systems utilize lithographically fabricated or glass chips to handle fluids at the nanoscale, allowing for contamination-free delivery to single cells. Both glass and microfluidic pipettes employ back-pressure or pneumatic control systems to regulate injection volumes between 1 and 100 nL, where regulated gas pressure drives fluid ejection through the tip while minimizing backflow. In pneumatic setups, a pico-injector applies adjustable positive pressure pulses, often 1-20 psi, to achieve precise dispensing, with back-pressure maintaining tip patency. Early prototypes occasionally incorporated air displacement principles for initial fluid loading, but modern designs prioritize pressure-based control for reliability. Applications of these pipettes span in vitro fertilization (IVF), where they facilitate into oocytes, and , enabling targeted delivery of neurotransmitters or genetic material into brain tissue slices or living neurons. They integrate with micromanipulators mounted on inverted microscopes, allowing sub-micron positioning and real-time visualization during injection into embryos or cellular structures.

Ultra-Low Volume Pipettes

Ultra-low volume pipettes are specialized instruments designed for precise dispensing and sampling in the sub-microliter range, specifically targeting femtoliter (10^{-15} L) to zeptoliter (10^{-21} L) volumes, enabling manipulations at the nanoscale for advanced scientific applications. These pipettes typically feature or nanotube tips fabricated from materials like , , or nanowires, with inner diameters ranging from 10 to 100 to achieve such minute volumes. For instance, attoliter (10^{-18} L) pipettes, often realized through nanopipette designs, facilitate single-molecule studies by confining analytes in isolated volumes sufficient for one or few molecules. The primary mechanisms for actuation in these pipettes involve electrokinetic flow or piezoelectric deformation to control movement without mechanical pistons, minimizing contamination and shear forces. Electrokinetic actuation exploits to drive and transport through charged nanopores, allowing tunable rates down to zeptoliters per second. Piezoelectric actuation, on the other hand, uses rapid deformation of piezo elements to generate pressure pulses for drop-on-demand ejection, achieving resolutions below 1 femtoliter in non-contact dispensing. In and , ultra-low volume pipettes enable low-input and analysis, such as spatial where femtoliter-scale sampling preserves limited material for high-resolution protein mapping.00287-9) They support ultra-sensitive assays, including nanoprobe arrays for protein detection from nanoliter samples, reducing reagent consumption in high-throughput sequencing workflows. As of 2025, trends in pipette miniaturization for emphasize integration with automated systems to accelerate , with advancements in nanofabrication enabling sub-femtoliter assays that cut costs and enhance precision in target validation. Key challenges in ultra-low volume pipetting include managing , which can alter volumes by up to 10% in open-air environments due to the high surface-to-volume ratio, necessitating humidity-controlled chambers or rapid transfer protocols. effects further complicate dispensing, as forces in nanopores can cause incomplete ejection or droplet instability, requiring optimized tip geometries and agents to ensure accuracy. These pipettes are often briefly integrated with microfluidic devices for sequential processing, enhancing throughput in molecular analyses.

Calibration and Quality Control

Procedures and Methods

The gravimetric method is the primary technique for calibrating pipettes to verify their by measuring the mass of dispensed liquid, typically , and converting it to volume. This approach relies on high-precision weighing to detect deviations in dispensed volumes, ensuring reliable liquid handling in settings. It is particularly effective for volumes ranging from microliters to milliliters and follows established protocols to account for environmental factors. In the gravimetric calibration process, an with at least 0.1 mg is used to weigh the dispensed . Measurements are performed at multiple points—typically 10%, 50%, and 100% of the pipette's nominal —to assess across its operating range. For each , the procedure involves 5 to 10 replicate dispensings to generate statistically robust data. Prior to dispensing, the pipette tip is pre-wet three times by aspirating and dispensing the test to minimize errors and ensure consistent delivery. The is then dispensed into a pre-weighed evaporation-resistant vessel, such as a weighing or flask, placed directly on the balance, and the weights are recorded after stabilization. Environmental conditions, including and , are monitored using a thermohygrometer to correct for variations in density and . The actual dispensed volume V is calculated using the formula: V = \frac{m}{\rho} \times Z where m is the measured mass of the dispensed liquid in grams, \rho is the density of water (approximately 0.998 g/mL at 20°C), and Z is the Z-factor, a correction term that accounts for the effects of air buoyancy, temperature, and relative humidity on the measurement. The Z-factor is determined from standard tables based on ambient conditions. Accuracy is evaluated as the mean relative error between the calculated volumes and the nominal volume, while precision is assessed using the standard deviation (SD) or coefficient of variation (CV) of the replicate measurements, with acceptable limits typically below 3% for accuracy and 1-2% for precision depending on the pipette volume. Essential equipment for gravimetric calibration includes the , thermohygrometer for recording ambient conditions, evaporation traps to prevent mass loss during weighing, and certified pipette tips to avoid or variability. For pipettes intended for viscous liquids, such as oils or buffers, alternative test fluids with known densities may be used instead of , following similar weighing and calculation steps adjusted for the fluid's properties. This method aligns with guidelines in ISO 8655 for non-volatile liquid testing.

Standards and Frequency

The ISO 8655 series, updated in 2022 for Parts 2-7 to refine metrological requirements and maximum permissible errors (including testing at 10%, 50%, and 100% of nominal volume) and in 2024 for Part 10 providing guidance on user competence, routine testing, and pipette suitability, establishes international metrological requirements for piston-operated volumetric apparatus, including . It defines maximum permissible errors, such as ±4% at the nominal volume of 10 μL , and mandates testing at multiple points across the pipette's range, typically 10%, 50%, and 100% of nominal volume, to ensure . In the United States, the National Institute of Standards and Technology (NIST) and the (USP) align their guidelines with ISO 8655 to promote to national and international standards. NIST 133, revised in 2025, updates procedures for volumetric glassware and apparatus, including pipettes, used in compliance testing for net contents, emphasizing Class A volumetric pipettes for high-precision measurements in regulated contexts. USP standards reinforce this , requiring calibrations linked to NIST references to support and in pharmaceutical and life sciences applications. Calibration frequency varies by usage and risk level, with standard laboratory pipettes recommended for checking every 6 to 12 months to maintain within ISO limits. In high-use settings, such as , intervals shorten to every 3 months to account for wear, while critical applications like forensic analysis may require monthly calibrations to meet stringent needs. Laboratories often track these schedules using (MTBF) data, which predicts reliability based on historical failure rates for specific pipette models and informs proactive maintenance. Documentation of pipette calibrations typically includes certificates detailing as-found results, which assess the device upon receipt before any adjustments, and as-left results, confirming post-adjustment compliance with standards like ISO 8655. These certificates provide through serial numbers, test conditions, and measurements, serving as essential records for audits and in regulated environments.

Ergonomics and Safety

Injury Risks

Pipetting, a repetitive task involving precise thumb and hand movements, is associated with several musculoskeletal disorders (MSDs), particularly in the upper . Common injuries include thumb tendonitis, such as De Quervain's tenosynovitis, which arises from repeated overstretching of the extensor pollicis brevis and abductor pollicis longus tendons during plunger depression and tip manipulation. Carpal tunnel syndrome, a nerve compression disorder, can also develop or exacerbate due to sustained pressure on the from forceful and repetitive thumb actions in thumb-push pipettes. These repetitive strain injuries (RSIs) stem from the high demands on thumb muscles, such as the abductor pollicis brevis, which can generate peak forces up to 68 N during dispensing tasks. Postural deviations during pipetting further contribute to injury risk by imposing static loads on the and . A "winged elbow" posture, where the elbow extends outward away from the body, transfers the arm's weight—approximately 6% of body weight—onto the and muscles, leading to reduced flow, , and diminished strength over time. Similarly, over-rotation of the or , often required to reach work surfaces or maintain grip, increases stress on the and can elevate the risk of strain. Stiff plungers in mechanical pipettes exacerbate these issues by requiring excessive force, with second-stop blowout forces reaching up to 10 in some models, amplifying joint at the carpometacarpal level. Key risk factors for these injuries include high repetition rates, awkward hand positions, and additional stressors like . Pipetting for 1-2 hours per day, equivalent to over 300 hours annually assuming 180-200 workdays, significantly elevates the prevalence of hand and compared to lower levels. Awkward grips, such as tight clutching or non-neutral deviation (e.g., 30° extension), hand muscles and promote ulnar drift, increasing irritation. In pipettes, motor-induced , though generally low, can compound when combined with repetitive motions, potentially aggravating and issues in prolonged sessions. Epidemiological data underscore the widespread impact, with up to 90% of workers pipetting more than 1 hour daily reporting hand or disorders. Overall, 40-80% of laboratory personnel experience work-related MSDs, with hand being particularly prevalent among those engaged in pipetting tasks. Risks are heightened with multi-channel pipettes, which demand greater thumb forces—up to 43% higher plunger resistance in some designs—due to simultaneous handling of multiple tips, leading to amplified strain on the hand and .

Prevention Strategies

To prevent repetitive strain injuries such as RSI associated with pipetting, maintaining proper is essential. Laboratory workers should position their elbows at a 90-degree with forearms to the floor, ensuring straight wrists in a position and a relaxed but firm on the pipette. Additionally, elevating the work surface to approximately mid-forearm height when seated allows for this , minimizing arm elevation and shoulder during tasks. Effective techniques further reduce . Taking micro-breaks of 1-2 minutes every 20 minutes—or approximately 5 minutes per hour—enables muscle and prevents buildup. Selecting light-touch pipettes that require thumb forces below 3 limits excessive pressure on the hand, while alternating hands between tasks distributes load and avoids overuse of one side. Best practices emphasize operational adjustments for smoother handling. Pre-wetting pipette tips by aspirating and dispensing the sample liquid 3-5 times before the actual transfer ensures consistent flow and reduces the need for additional force during aspiration. Limiting continuous pipetting sessions to under 1 hour, followed by a change in activity, helps mitigate cumulative strain. Incorporating simple stretch exercises, such as wrist flexes—extending the arm with palm facing up and gently pulling fingers back with the opposite hand for 15-30 seconds—during breaks promotes flexibility and relieves tension.

Accessories and Automation

Stands and Manual Aids

Pipette stands provide essential storage solutions for manual pipetting, typically designed as or linear holders accommodating 1 to 6 pipettes to maintain and accessibility in settings. stands feature a rotating base for quick pipette selection, often constructed from chemically resistant materials such as , , or plastic, which ensure durability and protection against common lab solvents. Linear stands, in contrast, arrange pipettes in a straight row for compact benchtop placement, similarly emphasizing stability through weighted bases to prevent tipping during use. Some advanced models incorporate UV-resistant features, such as UV-C sterilization systems that deliver 360-degree exposure to destroy up to 99% of DNA and microbial contaminants on pipette shafts, thereby minimizing cross-contamination risks without requiring disassembly. Additionally, stands compatible with recharging electronic pipettes include integrated docking stations that simultaneously store and charge devices, supporting models like those from Thermo Fisher or INTEGRA for uninterrupted . Manual aids for pipetting focus on simple, non-motorized tools that enhance precision and safety during transfer, particularly with serological pipettes. Rubber bulb fillers, often equipped with three s, enable one-handed control: one valve releases air from the , another draws into the pipette, and the third dispenses it accurately, fitting pipettes up to 50 mL or more. These devices, made from or chemical-resistant with or valves, serve as three-valve controllers specifically for serological applications, allowing efficient filling and emptying without complex setup. bulbs represent a core variant, designed explicitly to eliminate mouth pipetting by creating through bulb compression, thus avoiding direct oral contact with potentially hazardous liquids. These stands and aids offer key benefits in environments, including contamination prevention through secure and sterile features, as well as workspace that reduces clutter and facilitates quick access to tools. Materials like , metal alloys, or robust plastics further contribute to longevity and resistance to , while organized pipette placement helps minimize tip waste by promoting efficient handling during daily setups. In practice, they support routine lab operations by integrating ergonomic elements, such as stable bases and lightweight designs, to alleviate strain during prolonged manual pipetting sessions.

Robotic and Electronic Systems

Electronic pipettes represent a significant advancement in automated handling, integrating motorized mechanisms with interfaces to enhance and reduce manual errors in workflows. These devices, such as the Andrew Alliance Pipette+, feature connectivity and are programmable through cloud-based software like OneLab, allowing users to design, share, and execute protocols remotely while ensuring and . Introduced in 2019, the Pipette+ supports single- and multi-channel configurations with volumes ranging from 0.2 μL to 10 mL, incorporating ergonomic designs and tip ejection for user comfort during extended use. Robotic systems build on electronic pipettes by enabling fully automated, high-throughput operations through integrated platforms that handle multiple steps without human intervention. The INTEGRA ASSIST PLUS pipetting robot, for instance, accommodates VOYAGER adjustable tip spacing pipettes, which allow flexible reconfiguration of channel distances for various plate formats, facilitating tasks like serial dilutions and plate filling with minimal setup. Similarly, the Eppendorf epMotion 5070 liquid handler features a modular deck for 96- and 384-well plates, supporting automated normalization, , and qPCR setups with precise pipetting across volumes from 0.2 μL to 50 mL. These systems often incorporate cloud-controlled elements, as seen in Alliance's ecosystem, where protocols can be monitored and adjusted via remote access to optimize workflow efficiency. Recent advancements in robotic pipetting emphasize for handling nanoliter volumes and contactless dispensing to minimize and consumable use. The Dispendix I.DOT system exemplifies contactless technology, utilizing solenoid-driven dispensing to transfer liquids from 8 nL to several milliliters without tips, achieving high-speed operations such as filling a 384-well plate in under 20 seconds. By 2025, trends toward compact, AI-assisted error correction in liquid handlers are emerging, for instance, real-time systems for robots like the Opentrons OT-2 that detect and correct pipetting errors such as missing tips or incorrect volumes; though integration remains vendor-specific and focused on real-time protocol adjustments. The global market for automated liquid handling systems is projected to reach $6.75 billion by 2030, driven by demand for scalable solutions in research-intensive fields. In applications like (HTS) for and , robotic pipetting accelerates processes by automating compound assays and , enabling the analysis of thousands of wells per run with reduced variability. For genomics workflows, such as next-generation sequencing (NGS) library preparation, systems like the I.DOT support precise, tipless dispensing to streamline qPCR setups and reduce cross-contamination risks. These technologies not only boost throughput but also enhance reproducibility in HTS, where robotic integration with detection systems facilitates rapid data generation for identification.

Alternatives

Non-Pipette Liquid Handling Methods

Non-pipette liquid handling methods employ advanced technologies to dispense precise volumes of liquids without contact or disposable tips, offering alternatives to traditional pipetting in settings. These approaches leverage physical principles such as acoustics, , piezoelectric effects, and capillarity to achieve high accuracy at microliter and nanoliter scales, particularly in , , and diagnostics. Acoustic droplet ejection (ADE) utilizes focused ultrasonic sound waves to generate and transfer nanoliter-scale droplets from a source well to a destination without physical contact. In systems like the acoustic liquid handler, originally developed by Labcyte and now produced by , acoustic energy is directed at the liquid in a source , creating droplets as small as 2.5 nanoliters that are propelled precisely to target locations. This tipless method enables transfers of up to 500,000 samples per day, supporting applications in and where sample integrity is paramount. Electrowetting and piezoelectric dispensing provide contactless options for , handling volumes below 1 microliter. on (EWOD) manipulates discrete droplets by applying voltage to alter surface wettability, enabling precise splitting, merging, and dispensing of nanoliter to picoliter volumes on chip surfaces without mechanical components. This technique supports integrated biochemical assays by controlling droplet motion through electrode arrays. Complementarily, piezoelectric dispensers use rapid deformation of piezo elements to eject droplets from nozzles, achieving volumes from 100 picoliters to 1 nanoliter at frequencies suitable for on-demand printing in diagnostic and pharmaceutical workflows. Devices like BioDot's Ultra Piezo exemplify this, accommodating diverse fluids including cells while varying drop size dynamically. Capillary action systems rely on passive surface tension-driven flow within microchannels or chips, eliminating the need for active pumping in diagnostic applications. These setups feature hydrophilic channels that draw and distribute liquids via , often integrated into paper-based or devices for , such as blood or detection. For instance, grooved paper pumps or PMMA micromachined chips enable controlled whole-blood flow rates without external power, facilitating rapid assays with minimal user intervention. These methods reduce contamination risks by avoiding physical contact and disposable consumables, while boosting operational speed through and compatibility—capable of handling thousands of transfers per hour compared to manual pipetting. In 2025, trends include AI-optimized ejection in acoustic systems, where algorithms enhance droplet precision by predicting fluid properties and adjusting waveforms in real-time for improved throughput in . Robotic pipettes serve as hybrid solutions, incorporating non-contact elements for select steps in automated workflows.

Sustainable Options

Sustainable options for pipettes emphasize reducing , promoting reusability, and utilizing recyclable or biodegradable materials, addressing the significant environmental footprint of laboratory liquid handling where single-use plastics contribute to millions of tons of annual in life sciences. Reusable glass serological pipettes, made from durable like BORO 3.3, offer a primary to disposable versions, as they can withstand repeated autoclaving and sterilization without compromising performance. These pipettes reduce by over 60% in settings, such as in a case study, and lower long-term costs despite higher initial investment due to their extended lifespan. In routine cell culture applications, reusable glass pipettes have demonstrated equivalence to single-use plastics in maintaining sterility and cell viability; for instance, a University of Exeter study found no contamination issues after dry-heat sterilization at 180°C for 120 minutes, with minimal additional labor of about one hour per week. Over a 10-year period, this approach cuts carbon dioxide equivalent (CO2e) emissions by 105.92 kg and costs by £408.78 per researcher, achieving a 21.79% lower environmental footprint after five years compared to disposables. Glass pipettes are particularly suitable for non-sterile research, quality control, and teaching tasks, though plastic remains preferable for highly contamination-sensitive sterile work. For pipette tips, which account for a large portion of plastic —up to 80% of clean in some facilities—eco-friendly racks and refill systems significantly mitigate impacts. The AHN CAPP PaperBox, constructed from recyclable and biodegradable , reduces by up to 60% while preserving tip sterility and compatibility with standard pipettes, and its space-efficient design further lowers transportation emissions. Similarly, Rainin TerraRack uses PET-based materials to consume 50% less and reduce by 80%, available in sterile configurations. Refill systems, such as TipRack or Rainin refills, cut usage by up to 85% compared to traditional racked tips by reusing durable boxes that can be autoclaved multiple times. Closed-loop recycling programs enhance for tips made from or recycled plastics; for example, Polycarbin provides tips from 100% recycled plastic and offers take-back services for boxes and clean labware, while operates similar programs to recycle uncontaminated plastics. Thin-walled tips and those using 90% renewable raw materials, like BRAND TipRack Eco, further minimize material needs without sacrificing accuracy. Long-lasting electronic pipettes, such as the BRAND Transferpette S, support through durability, enduring 500,000 dispensing strokes and 200,000 tip ejections, reducing replacement frequency. Labs can optimize these options via waste audits and supplier consultations to align with standards like the Environmental Impact Factor for low-impact choices.

References

  1. [1]
    2: Basic Lab Equipment - Medicine LibreTexts
    May 5, 2025 · Pipetting ; Serological/Graduated Pipettes · Serological pipette · 8 ; Volumetric Pipettes · Volumetric pipette · 9 ; Transfer/Disposable Pipettes.Missing: instrument | Show results with:instrument
  2. [2]
    Pipetting Protocol - Addgene
    The purpose of the pipette tip is so that the same pipette can be used for measuring different samples without cross contamination as long as the tip is changed ...Missing: instrument | Show results with:instrument
  3. [3]
    Revisiting the Micropipetting Techniques in Biomedical Sciences - NIH
    There are many types of air and positive displacement micropipettes available commercially, such as singlechannel, multi-channel, manual or electronic, etc.Missing: instrument | Show results with:instrument<|control11|><|separator|>
  4. [4]
    Pasteur Pipette | National Museum of American History
    This glass pipette, from the University of Michigan Medical School Hygienic Laboratory, was used to transfer small quantities of liquids from one vessel to ...
  5. [5]
    When a common problem meets an ingenious mind - PMC - NIH
    The modern micropipette has achieved such high visibility for obvious reasons: it is without exaggeration, the most widely used instrument in biology and ...
  6. [6]
    Guide to Pipettes: Principle, Types & Key Uses - Microbe Notes
    Nov 1, 2024 · A pipette is a lab device used to measure out or dispense small amounts of liquid in volumes of milliliters (mL) or microliters (μL).Principle of Pipette · Parts of Pipette · Types of Pipette · Applications of Pipette
  7. [7]
    Understanding Pipettes: Essential Tools for Precision in the Laboratory
    A pipette is a fundamental laboratory instrument used to transport a measured volume of liquid, often as a critical step in chemical, biological, and clinical ...
  8. [8]
    What pipettes are used for | User Guide - POBEL
    Oct 3, 2024 · A pipette is a vital instrument in laboratories, designed to measure and transfer precise volumes of liquids with high accuracy.
  9. [9]
  10. [10]
    What Are the Benefits of Positive-Displacement Versus Air-Displacement Pipettes?
    ### Summary of Positive Displacement Pipettes from Gilson Article
  11. [11]
    [PDF] Fundamentals of dispensing - Eppendorf
    Air-cushion principle (air displacement). Air-cushion pipettes consist of a piston-cylinder system which performs the actual measurement (Fig. 1). An air-.
  12. [12]
    [PDF] The Science of Pipetting to Perfection - Eppendorf
    Positive displacement. The positive displacement principle is based upon the concept that a pipette tip contains a moveable piston that contacts the liquid ...<|separator|>
  13. [13]
    Laboratory Orientation and Testing of Body Fluids and Tissues for ...
    Jun 28, 2023 · Positive displacement pipettes work by having a piston-integrated tip. The piston makes contact with the liquid, and a positive wiping action of ...
  14. [14]
    [PDF] SOP 14 Gravimetric Calibration of Volumetric Standards Using an ...
    The accuracy attainable depends on the ability of the operator to read and set the meniscus, uncertainties of the standard weights, the air buoyancy corrections ...
  15. [15]
    Working with volumetric instruments - brand.de
    Correct meniscus setting is a prerequisite for accurate volumetric measurement. Meniscus. Concave meniscus in a graduated pipette. In the case of a concave ...
  16. [16]
    [PDF] Thermo Scientific Good Laboratory Pipetting (GLP) Practices
    To empty the tip completely, the operating button is pressed to the second stop (blow-out). Dispensing the liquid (step 4). Aspirating the liquid (steps 1-3).
  17. [17]
    Pipetting Recommendations for Different Sample Types - UK
    During the aspiration and dispensing, use very slow plunger movements. When aspirating, hold the tips in the liquid for a few seconds, after the plunger is in ...
  18. [18]
    Shattering creations: a short history of laboratory glassware
    Jul 16, 2024 · The earliest examples recognisable as “scientific” glassware come from the alchemists' laboratories of Hellenistic Egypt from 323 BC to 30 BC.
  19. [19]
    A Brief History of Pipettes and Liquid Handling - Labmate Online
    Jan 16, 2022 · French chemist and microbiologist Louis Pasteur (1822-1895) is widely credited with inventing the first pipettes. Pasteur is often referred to ...
  20. [20]
    Joseph Lister - Wikipedia
    Edinburgh 1869–1877. edit. Micro-pipette used by Lister that dispensed a bacterial solution diluted to contain an average of "rather less than one bacterium" ...Joseph Jackson Lister · Agnes Syme Lister · John Hunter (surgeon)Missing: adjustable | Show results with:adjustable
  21. [21]
    File:Micro-pipette used by Lord Joseph Lister in his experiments on ...
    Mar 2, 2022 · The micro-pipette was designed in such a manner that it could dispense “rather less than one bacterium” per drop of diluted bacterial solution.
  22. [22]
    Volumetric pipette - National Museum of American History
    Volumetric pipettes are designed to be highly accurate for a specific volume. ... The glassware in the Keppel collection covers the 19th and early 20th centuries.Missing: introduction | Show results with:introduction
  23. [23]
    Standing the test of time - Laboratory News
    Oct 25, 2011 · The modern day air displacement pipette was developed by Warren Gilson and Henry Lardy from a device used to measure the amount of oxygen used ...
  24. [24]
    What Is A Pipette - Science and History - Precise Technical Solutions
    Dr. Heinrich Schnitger, from Marburg, Germany, invented the first micropipette in 1957. This model measured and transported a fixed amount. Later, the co- ...
  25. [25]
    The Evolution Of Pipette Calibration Service Part 1
    The mechanical pipette (micropipette) was invented in the early 1960s and has historically become one of the most significant laboratory tools over the last ...
  26. [26]
    [PDF] Evolution of the
    Heinrich Schnitger developed the first piston-stroke pipette while at the University of Marburg, making the process of pipetting much faster. Simple, elegant, ...Missing: history | Show results with:history
  27. [27]
  28. [28]
  29. [29]
    My Pipette Creator | Thermo Fisher Scientific - US
    My Pipette Creator is a web-based app for programming, sharing, and downloading protocols for Thermo Scientific E1-ClipTip pipettes, boosting productivity.
  30. [30]
    Real-time AI-driven quality control for laboratory automation: a novel ...
    Mar 10, 2025 · The current volume detection system achieves 95% accuracy, sufficient for detecting large pipetting errors. However, since most pipette ...
  31. [31]
    Trends in Lab Automation Liquid Handling - Dispendix
    Mar 18, 2025 · Recent advancements in lab automation liquid handling, including contactless dispensing, miniaturization, AI integration, and cloud control, enhance accuracy, ...
  32. [32]
    Pipette Tips Market Key Players And Growth Drivers Report 2025
    In stockFor instance, in July 2024, GenFollower Biotech CO. LTD., a China-based manufacturing company, launched two types of 5mL large volume pipette tips. These new ...
  33. [33]
    Pipet vs Pipette vs Micropipette: Key Differences Explained
    Aug 1, 2025 · The term “pipet” is more commonly used in American English, while “pipette” is the preferred spelling in British English. But both words ...<|separator|>
  34. [34]
  35. [35]
    Pipette Types for Different Applications | Thermo Fisher Scientific - US
    Serological pipettes are used in cell and tissue culture applications, and in general laboratory liquid dosage when more than 1mL volumes are pipetted.
  36. [36]
    What is the Difference Between TD & TC Pipettes? - Westlab Canada
    Jul 19, 2017 · Most typical graduated pipettes or bulb pipettes are usually calibrated to deliver (TD), whereas capillary pipettes are adjusted to contain (TC) ...
  37. [37]
  38. [38]
    How to calculate the accuracy & precision of a pipette | INTEGRA
    Check if your pipette needs to be calibrated: Learn how to calculate pipette accuracy and precision to compare the values obtained with the specifications.
  39. [39]
    ISO 8655-1:2022 - Piston-operated volumetric apparatus — Part 1
    In stock 2–5 day deliveryThis document specifies general requirements for piston-operated volumetric apparatus (POVA). It is applicable to pipettes, burettes, dilutors, dispensers.
  40. [40]
  41. [41]
  42. [42]
    Everything you need to know about the different types of pipettes
    What is a pipette? What is the difference between the various types of pipettes? How do positive and air displacement pipettes work? Get the answers!Missing: glass plastic variable
  43. [43]
  44. [44]
    Pipettes - Principles, Components, Types, Operation - Scitek Global
    Jan 6, 2025 · There are three basic types of pipettes: glass, plastic and electric. ... Manual and motorized single-channel variable-volume and fixed-volume ...Missing: classification | Show results with:classification
  45. [45]
    [PDF] The Use of Volumetric Pipets with NIST Handbook 133, Checking ...
    A Transfer (volumetric pipet) is calibrated “to deliver” a specific volume in a single delivery and comes in a variety of sizes including 10 mL, 25 mL, 50 mL, ...
  46. [46]
    E969 Standard Specification for Glass Volumetric (Transfer) Pipets
    This specification covers volumetric pipets of two classes. Class A, Precision Pipet and Class B, General Purpose.
  47. [47]
  48. [48]
    [PDF] CHEM 334 Quantitative Analysis Laboratory
    Oct 29, 2018 · Pipettes. The pipette is used to transfer a volume of solution from one container to another. Most volumetric pipettes are calibrated To ...
  49. [49]
    [PDF] Laboratory Study Guide - Wisconsin DNR
    Serological pipets can be used to measure various volumes from a single pipet due to their volume gradations. There are two kinds of serological pipets,"blow ...
  50. [50]
    [PDF] Introduction to Laboratory Methods - TN.gov
    Jan 16, 2013 · • Graduated (Mohr). • Serological. • Volumetric. – Mechanical ... Examine pipets A and B. Which is the Serological and which is the. Mohr?
  51. [51]
    Procedure - FSU Chemistry & Biochemistry
    The goal of this exercise is to sharpen your skills in using volumetric glassware. You will be issued a sample of HCl solution. You will be asked to dilute it.
  52. [52]
    Corning Stripette Paper/Plastic-Wrapped Disposable Polystyrene ...
    In stock $88 deliveryThis Item: Corning™ Stripette™ Paper/Plastic-Wrapped Disposable Polystyrene Serological Pipettes, Sterile. $619.00 / Case of 1000.
  53. [53]
    [PDF] Simulation and Modification of Standard Pipette Tip for Atomizing ...
    This error is likely a limitation of the equipment used as glycerol is very dense, viscous and has a high surface tension with Newtonian fluid behavior (12).
  54. [54]
    Proper Use of Positive-Displacement Pipettes
    ### Summary of Positive-Displacement Pipettes from Gilson Article
  55. [55]
    Positive Displacement Pipettes & Dispensers | Eppendorf
    **Summary of Positive Displacement Pipettes & Dispensers (Eppendorf):**
  56. [56]
    Pasteur Pipette - an overview | ScienceDirect Topics
    A Pasteur pipette is defined as a fine plastic or glass tube used for transferring small volumes of liquid, which aids in achieving precise filling of counting ...
  57. [57]
    Transfer Pipets | Thermo Fisher Scientific
    Transfer pipets are plastic and offered in both graduated and ungraduated formats with integral bulbs or accessory bulbs for transferring liquids.
  58. [58]
  59. [59]
  60. [60]
    What are the Different Types of Pipettes? | from Cole-Parmer Blog
    May 8, 2022 · Transfer Pipettes/Pasteur Pipettes transfer small quantities of liquids. Plastic bulb pipettes are typically not precise enough to be used for ...
  61. [61]
    Dosys™ classic 163 - syringe pipette - Socorex
    Self-refilling, two-ring and automatic syringe pipette with integrated, Luer Lock valve system. Volumes ranging 0.025 to 10 mL.
  62. [62]
  63. [63]
    [PDF] the van slyke apparatus.pdf - Digital Commons @ RU
    Best described as a "quantitative gas analyzer," the. Van Slyke instrument determined the amount of a given substance in the blood or other fluid by measuring ...Missing: pipette | Show results with:pipette
  64. [64]
    Ostwald-Folin Pipets - Fisher Scientific
    Also called blood pipets, these are volumetric glass or plastic transfer pipets used for whole blood, serum, and other viscous fluids; most Ostwald-Folin pipets ...Missing: wide- bulb early 1900s
  65. [65]
    What is the Ostwald–Folin pipette? - Microlit
    Ostwald-Folin pipettes, also known as blood pipettes, are volumetric glass or plastic transfer pipettes that are used to transfer whole blood, serum, and other ...Missing: wide- bulb early 1900s
  66. [66]
  67. [67]
    338 INORGANIC ANALYSIS. Preparation of Petermann's ...
    )-The use of the Winkler-Dennis conibustion pipette, even as modified by the authors, presents certain difficulties and inherent errors. In this pipette a.
  68. [68]
    The Winkler Method - Measuring Dissolved Oxygen - SERC (Carleton)
    The Winkler method measures dissolved oxygen in freshwater using titration. A sample is filled, reagents are added, and then titrated to a color change.
  69. [69]
  70. [70]
    Microinjection of Zebrafish Embryos to Analyze Gene Function - NIH
    Mar 9, 2009 · With a micropipette puller, pull a 1.0mm OD glass capillary into two needles and store in a 150mm Petri dish by laying over silly putty ramps.
  71. [71]
    Microinjection-based System for In Vivo Implantation of Embryonic ...
    Feb 17, 2019 · Pull glass capillaries using a micropipette puller. · Coat the inner and external surfaces of the glass capillary with silicone. · The morning of ...
  72. [72]
    A Microfluidic Pipette for Single-Cell Pharmacology - ACS Publications
    In short, the microfluidic pipette allows for complex, contamination-free multiple-compound delivery for pharmacological screening of intact adherent cells. ACS ...
  73. [73]
    Microfluidic lab-on-a-chip platforms: requirements, characteristics ...
    Jan 25, 2010 · This critical review summarizes developments in microfluidic platforms that enable the miniaturization, integration, automation and parallelization of (bio-) ...Missing: nano- | Show results with:nano-
  74. [74]
    Printed droplet microfluidics for on demand dispensing of picoliter ...
    Jul 31, 2017 · Here we present printed droplet microfluidics, a technology to dispense picoliter droplets and cells with deterministic control.
  75. [75]
    [PDF] Model PLI-100A Pico-Injector - Warner Instruments
    The PLI-100A Pico-Injector reliably delivers ejections from femtoliters to nanoliters through micropipettes by applying a regulated pressure ...Missing: design nL
  76. [76]
    [PDF] microinjection - Warner Instruments
    This adjustable pressure keeps a positive pressure on the injection pipette before and after injections. This eliminates dilution caused by capillary action and ...Missing: design 1-100 nL
  77. [77]
    Micromanipulation Applications: Food, Genetics, Fertility and more
    Micromanipulation has been especially useful in IVF in assisting embryo hatching in women who have issues with embryo implantation. These micromanipulation ...
  78. [78]
    Robotic platform for microinjection into single cells in brain tissue
    A typical microinjection experiment involves a user guiding the injection micropipette to the surface of the tissue, inserting the pipette tip into the tissue ...
  79. [79]
    Complete Microinjection System: Microscopes, Micromanipulators ...
    Microinjection is normally performed under a specialized microscope with the aid of a micromanipulator which allows for small movement under high magnification.
  80. [80]
    Label-Free Monitoring of Single Molecule Immunoreaction with a ...
    Jul 24, 2017 · The nanopipette has been employed for the single molecule analysis due to its advantage of easy fabrication and controllable diameter.
  81. [81]
    Visualization of Ion Fluxes in Nanopipettes: Detection and Analysis ...
    Nov 30, 2021 · We demonstrate a laser scanning confocal microscope (LSCM) approach to tracking the ingress of dye into a nanopipette (20–50 nm diameter end opening).
  82. [82]
  83. [83]
    NanoProbeArrays for the Analysis of Ultra-Low-Volume Protein ...
    Applications of proteomics range from basic research on the regulation of gene expression, protein networks, and biochemical activities, to applied research ...
  84. [84]
    MINIATURIZATION MEANS MORE THAN LOW VOLUMES
    Assay miniaturization in high-throughput screening (HTS) has been adopted by the pharmaceutical industry to accelerate the R&D cycle and to reduce costs.
  85. [85]
    [PDF] Femtoliter Volumetric Pipette and Flask Utilizing Nanofluidics
    Dec 26, 2019 · A nanofluidic device, which incorporated an 11 fL volumetric pipette and a 50 fL volumetric flask, was designed and fabricated, and the ...Missing: zeptoliter | Show results with:zeptoliter
  86. [86]
    Discrete Femtolitre Pipetting with 3D Printed Axisymmetrical ...
    Oct 15, 2023 · A new concept is proposed that makes use of axisymmetrical phaseguides inside a microfluidic channel to pipette liquid in discrete steps of known volume.Missing: ultra- zeptoliter
  87. [87]
    ISO 8655 International Standards for Pipettes | Rainin - Mettler Toledo
    ISO 8655 is the global standard that defines how Pipettes/POVA (Piston Operated Volumetric Apparatus) devices should be manufactured and tested for accuracy.
  88. [88]
  89. [89]
    [PDF] NIST HB133: Checking the Net Contents of Packaged Goods
    Dec 12, 2024 · This 2025 edition includes amendments made through the. Committee on Laws and Regulations of the National Conference on Weights and Measures. ( ...
  90. [90]
    The Use of Volumetric Pipets with NIST Handbook 133, "Checking ...
    Jul 7, 2014 · Guidance on the use of Class A pipets for precision measurement in package testing.Missing: glassware pipettes
  91. [91]
    Pipette Calibration Using a Balance - ISO 8655 - Mettler Toledo
    It supports accurate and traceable pipette calibrations according to ISO 8655 and 21 CFR Part 11 requirements.
  92. [92]
    Pipette Calibration Frequency Guidelines
    Aug 27, 2025 · Standard Laboratory Pipettes: Every 6 months for moderate use. · High-Use Pipettes (daily usage): Every 3 months or quarterly. · Critical ...
  93. [93]
    Establishing a Pipette Calibration Schedule - Lab Manager
    Sep 6, 2023 · MTBF allows you to figure out how often to calibrate your pipette set as well as identify which pipettes need calibration more often.
  94. [94]
    Pipette Calibration & Maintenance | Thermo Fisher Scientific - US
    ... Calibration certificate includes as left data • Option available for as-found data • Pipette adjustments comply with ISO8655 • Certificate & calibration sticker ...
  95. [95]
    ACC Calibration Certificate Explanation - Mettler Toledo
    2 | As-found and as-left: The calibration certificate includes the assessment before (as-found) and after (as-left) any adjustment or repair. As-found ...
  96. [96]
    Analysis of the musculoskeletal loading of the thumb during pipetting
    Previous epidemiological studies indicate that the use of thumb-push mechanical pipettes is associated with musculoskeletal disorders (MSDs) in the hand.
  97. [97]
    Establishing Good Ergonomic Work Practices when Pipetting
    Holding a pipette with the elbow extended (winged elbow) in a static position places the weight of the arm onto the neck and shoulder muscles and reduces ...
  98. [98]
    An investigation of hand forces and postures for using selected ...
    (1994) found that if pipetting was performed for more than 300 h/year, the prevalence of hand and shoulder pain among laboratory workers increased, compared to ...
  99. [99]
    [PDF] The Ergonomics of Pipetting Forces are Affected by Pipette Selection
    ergonomics can lead to fatigue, pain and the risk of injuries. ... This can be particularly helpful with multichannel pipettes, which have the highest plunger ...
  100. [100]
    Work-related musculoskeletal problems related to laboratory training ...
    Oct 29, 2018 · Medical science laboratory technicians are not immune with reported work-related musculoskeletal problems between 40 and 80%. Similar data is ...
  101. [101]
    Ergonomics - MIT EHS
    Your elbows should be at a 90-degree angle, tucked close to your body, and ... Use latch-mode or electronic pipettes for repetitive pipetting. Take a 1 ...
  102. [102]
    [PDF] Ergonomics - Good For Everybody - ORS
    Use latch-mode or electronic pipettors for repetitive pipetting. ... Forearms should be parallel to the floor. (approximately 90 degree angle at elbow).<|separator|>
  103. [103]
    Pipette Ergonomics - UC Davis Safety Services
    Maintain straight wrists - Do not twist or rotate your wrists while using the pipette · Always have a relaxed but firm grip on the pipette · Keep elbows and your ...Missing: strategies | Show results with:strategies
  104. [104]
    Prevention - ORS - NIH
    Use minimal force when applying pipette tips. Keep samples and instruments within easy reach. Use an adjustable stool or chair when sitting at a lab bench (see ...Missing: strategies | Show results with:strategies
  105. [105]
    Ergonomic pipettes and pipetting guidelines - INTEGRA Biosciences
    The likelihood of developing an RSI from pipetting is dependent on various risk factors. The 3 major ones are posture, force and repetition.
  106. [106]
    Pipetting | Office of Public Safety & Emergency Management
    Repetitive-strain injuries can occur when pipetting for extended periods of time. You may be at risk if you feel weakness or pain in your thumb or wrist.
  107. [107]
    10 Steps to Improve Pipetting Accuracy | Thermo Fisher Scientific - US
    Improve pipetting accuracy by pre-wetting the tip, working at temperature equilibrium, removing droplets, using forward mode, and pausing consistently.
  108. [108]
    Flexibility/Stretching Exercises - Pitt Safety
    Hold arm straight at waist height with palm facing away from you and fingers pointing up. · Hold onto palm of hand and stretch wrist back. · Make sure the fingers ...
  109. [109]
    Top Trends Driving Growth in Electronic Pipette Systems Market
    Electronic Pipette Systems Trends 2026: Explore exclusive insights, growth forecast, and strategy analysis at Verified Market Reports.Missing: micropipette Bluetooth
  110. [110]
  111. [111]
  112. [112]
  113. [113]
  114. [114]
  115. [115]
  116. [116]
    E1-ClipTip™ Electronic Pipette Charging Stand
    6–10 day deliveryE1-ClipTip™ Electronic Pipette Charging Stand. Conveniently charge and store one or three pipettes with these custom charging stands. Available in 3 Pipettes.
  117. [117]
    Storage, Charging and Communication Options | INTEGRA
    The linear stand accommodates all types of INTEGRA pipettes. It holds up to 12 pipettes or four charging / communication stations.
  118. [118]
    Fisherbrand Rubber Bulb-Type Safety Pipet Fillers Black | Buy Online
    In stock $83.50 delivery100% natural rubber patented pipet fillers eliminate mouth pipetting and handling of hazardous materials. Two stainless-steel ball valves control vacuum.Missing: benefits | Show results with:benefits
  119. [119]
    Pipette Bulb Filler with 3 Valves (BrandTech)
    In stock $9.85 deliveryFill pipettes with this rubber pipette filler bulb. Safely and accurately dispense liquids into pipettes with the 3 valves on this pipet aid.Missing: safety benefits contamination
  120. [120]
    Pipet Fillers - Fisher Scientific
    Manual pipet fillers. Application-specific bulbs for Westergren and other specific methods; Plain and safety bulbs with vacuum, aspirate, and dispense valves ...Missing: bulb benefits contamination
  121. [121]
    Fisherbrand Silicone Bulb-Type Safety Pipet Fillers Black | Buy Online
    In stock $79 deliveryThese chemical-resistant, resilient, silicone pipet fillers with glass valves. Glass valves improve worker safety by eliminating mouth pipetting and handling ...Missing: benefits | Show results with:benefits
  122. [122]
    Bluetooth electronic pipettes - repeatable and traceable
    Pipette+ enables Bluetooth electronic pipettes to be remotely programmed and tracked using Andrew Alliance's lab automation software environment, OneLab.Missing: trends | Show results with:trends<|control11|><|separator|>
  123. [123]
    [PDF] Andrew Alliance Bluetooth Electronic Pipette
    Based on the Picus design, this pipette has Bluetooth, is light, small, ergonomic, and has electronic tip ejection, and is compatible with OneLab.
  124. [124]
    ASSIST PLUS | Pipetting Robot - INTEGRA Biosciences
    Rating 4.8 (144) ASSIST PLUS pipetting robot using the VOYAGER adjustable tip spacing pipette to aspirate liquid from Eppendorf. Automated pipetting: ASSIST PLUS pipetting ...Integra · D-ONE | Single Channel... · Download VIALAB
  125. [125]
    epMotion® 5070 - Eppendorf
    The epMotion 5070 is a compact, automated pipetting solution for routine tasks like PCR, serial dilutions, and sample transfer. It has four worktable positions.
  126. [126]
    Meet the Andrew Alliance Pipette+ - Waters Videos
    These smart, electronic pipettes allow you to easily design and share protocols with the intuitive OneLab user-interface. Bluetooth and an onboard calculator ...
  127. [127]
    Automated Pipetting - Eppendorf epMotion
    Eppendorf epMotion offers 96-channel semi-automated pipettes, compact pipetting robots, and models for NGS library prep, (q)PCR setup, and cell-based assays.
  128. [128]
    Liquid Handling System Market Growth, Drivers and Opportunities ...
    7-day returnsMarket Growth: The global liquid handling systems market size was valued at USD 4.34 billion in 2024 and is expected to reach USD 6.75 billion by 2030, growing ...
  129. [129]
    High-Throughput Screening (HTS) - Beckman Coulter
    HTS brings together robotic automation, liquid handling, and signal detection in a combinational approach to produce rich data sets in a short period of time.
  130. [130]
    I.DOT Non Contact Dispenser - Dispendix
    I.DOT: User-friendly, precise liquid handler with minimal consumables, perfect for NGS, qPCR, and more. Enhance preparation efficiency.Missing: contactless | Show results with:contactless
  131. [131]
    A Robotic Platform for Quantitative High-Throughput Screening - PMC
    A fully integrated and automated screening system for qHTS at the National Institutes of Health's Chemical Genomics Center.
  132. [132]
    Echo Acoustic Liquid Handlers - Beckman Coulter
    Originally developed by Labcyte, Echo Acoustic Liquid Handlers (Dispensers) transfer liquid droplets as small as 2.5 nanoliters with sound waves.
  133. [133]
    Acoustic Droplet Ejection Technology and Its Application in High ...
    Dec 9, 2015 · The ADE instrument chosen for this project was Labcyte's Echo 555 Series Liquid Handler. The Echo 555 has both DMSO and aqueous dispense ...
  134. [134]
    Echo Acoustic Liquid Handling Technology - Beckman Coulter
    Echo technology uses acoustic energy to eject precise droplets of liquid, transferring up to 750,000 samples daily without touching them.Missing: Labcyte | Show results with:Labcyte
  135. [135]
    Electrowetting-based actuation of droplets for integrated microfluidics
    We are reporting here an alternative approach to microfluidics based upon the micromanipulation of discrete droplets of aqueous electrolyte by electrowetting.
  136. [136]
    BioDot Introduces the Ultra Piezoelectric Dispensing Technology
    BioDot's Ultra Piezo Technology is a non-contact liquid handling and spotting system. The technology dispenses with a wide dynamic volume ranges.
  137. [137]
    Droplet dispensing and splitting by electrowetting on dielectric ...
    The present study investigates two essential capabilities of electrowetting on dielectric digital microfluidics - 1) high precision and consistency in ...
  138. [138]
    Capillary microfluidics for diagnostic applications - Frontiers
    This review examines the fundamental concepts of capillary-driven microfluidics, emphasizing significant progress in the design of capillary pumps and valves.
  139. [139]
    Paper-based passive pumps to generate controllable whole blood ...
    The proposed grooved paper pumps are capable of generating a controllable flow of complex biofluids within microfluidic devices with minimal user intervention.
  140. [140]
    Capillary-Driven Flow Microfluidics Combined with Smartphone ...
    Jul 22, 2020 · A micromachined polymethyl methacrylate (PMMA) chip was used to create a capillary flow inside microchannels, and the meniscus was monitored via ...
  141. [141]
    Automated liquid-handling operations for robust, resilient, and ...
    Dec 15, 2022 · This makes transfers more accurate and less prone to contamination than its counterparts, which handle liquids via pipetting, but its ...
  142. [142]
    Benefits of Acoustic Liquid Handling in Drug Discovery
    Feb 29, 2024 · Our instrument applies Acoustic Droplet Ejection (ADE) to accurately and rapidly transfer up to 700 drops of fluid per second.5 The acoustic ...
  143. [143]
    Acoustic Liquid Handling Market Research Report 2033 - Dataintelo
    Advancements include higher throughput, miniaturized and integrated systems, improved user interfaces, AI-driven workflow optimization, and compatibility with ...
  144. [144]
    Glass Vs Plastic Pipettes: Which Supports Sustainable Laboratory ...
    Sep 1, 2025 · Are glass pipettes more sustainable than plastic? Yes. Glass pipettes are reusable, reducing waste and long-term costs compared to disposable ...
  145. [145]
  146. [146]
  147. [147]
    Reusable glassware for routine cell culture—a sterile, sustainable ...
    Sep 24, 2024 · Single use culture flasks, plates and serological pipettes are often made from polystyrene, which is less recyclable and generates more ...
  148. [148]
    Sustainability in Life Sciences: The Role of Eco-Friendly Tip Racks
    Discover how eco-friendly pipette tip racks like the AHN CAPP® PaperBox help life science labs cut plastic waste by up to 60%, maintain sterility, ...
  149. [149]
  150. [150]
  151. [151]
    Eco-Friendly Alternatives | Office of Energy & Sustainability
    Polycarbin supplies pipette tips made entirely of recycled plastic and takes back pipette tip boxes and clean lab plasticware to recycle in a close loop. Qiagen ...
  152. [152]
  153. [153]