Fact-checked by Grok 2 weeks ago

Dithizone

Dithizone, also known as diphenylthiocarbazone, is an organosulfur compound with the molecular formula C₁₃H₁₂N₄S and a molecular weight of 256.33 g/mol, widely utilized as a chelating agent in for the detection, extraction, and quantification of including , , mercury, lead, and . It appears as a dark brown or black crystalline powder that decomposes at 168°C and is soluble in organic solvents such as , , and , but insoluble in water. First synthesized in 1878 by , dithizone is typically prepared through the reaction of diphenylthiocarbazide with in followed by acidification; it forms intensely colored complexes with metal ions, enabling sensitive spectrophotometric assays at trace levels, such as parts per billion for lead. In addition to its primary role in environmental and industrial metal analysis, dithizone serves as a reagent for assessing the purity of human pancreatic islet preparations in diabetes research and has been investigated as a potential chelator for heavy metal poisoning, though its clinical use is limited by toxicity concerns including skin and eye irritation. It also finds applications in inducing experimental diabetes in animal models by selectively chelating zinc from insulin granules, leading to beta-cell degranulation and hyperglycemia. Due to its stability under recommended storage conditions and incompatibility with strong oxidizers, dithizone is handled as an ACS reagent-grade material in laboratory settings, often modified for use in electrodes or nanomaterials to enhance heavy metal detection in aqueous solutions.

Nomenclature and structure

Names and identifiers

Dithizone is the primary common name for this organosulfur compound, widely recognized in for its use as a metal chelating agent. It is also commonly referred to as diphenylthiocarbazone. The systematic IUPAC name for dithizone is 3-(phenylamino)-1-(phenylimino), reflecting its thiourea derivative structure with phenyl substituents. Dithizone has the molecular formula C_{13}H_{12}N_4S and a molecular weight of 256.33 g/mol. Its is 60-10-6, a assigned by the . Key structural identifiers include the (InChI): 1S/C13H12N4S/c18-13(16-14-11-7-3-1-4-8-11)17-15-12-9-5-2-6-10-12/h1-10,14H,(H,16,18), and the InChIKey: UOFGSWVZMUXXIY-UHFFFAOYSA-N. The canonical SMILES notation is S=C(NNc1ccccc1)N=Nc1ccccc1. A list of additional synonyms from chemical databases includes dithizon, ditizon, carbazone, diphenylthiohydrazone, USAF EK-3092, diazenecarbothioic acid phenyl- 2-phenylhydrazide, and (phenylazo)thioformic acid 2-phenylhydrazide.

Molecular structure

Dithizone consists of a thiocarbazone core, characterized by a central carbon atom bonded to a and flanked by and azo linkages, with phenyl groups attached to the terminal atoms of the (Ph-NH-NH-) and azo ( -N=N-Ph) moieties. This arrangement yields the C₁₃H₁₂N₄S and enables the molecule's role as a multidentate through its and donor sites. The key functional groups in dithizone include the thiocarbonyl (C=S), azo (N=N), (C=N), and (NH) moieties, which contribute to its electronic delocalization and reactivity. These groups facilitate intramolecular hydrogen bonding and π-conjugation along the backbone, influencing the molecule's conformational flexibility. Dithizone undergoes thione-thiol and azo-hydrazone tautomerism, resulting in multiple isomeric forms; the six possible tautomers have been identified via (DFT) calculations, with the lowest-energy structures involving proton shifts between the imine nitrogen and sulfur or between the azo and hydrazone nitrogens. In solution, the predominant tautomer is the red thiol-azo form, where the (SH) and azo (N=N) configurations dominate due to stabilization by interactions and intramolecular hydrogen bonding. The around the N=N bond exhibits , with the being thermodynamically stable and prevalent, as confirmed by NMR studies on analogous dithiocarbazinic derivatives. Crystal structures of dithizone and its derivatives, derived from and supported by DFT optimizations, show a nearly planar conjugated core with the two phenyl rings twisted out of the plane by approximately 30–50° to minimize steric repulsion. Selected bond lengths include C=S at approximately 1.68 and N=N at approximately 1.25 , indicative of partial double-bond character and delocalization. UV-Vis spectroscopy confirms the tautomerism and conformational features, with the green form displaying absorption maxima at around 450 nm (corresponding to π→π* transitions in the thione-hydrazone tautomer) and the red form at 620 nm (associated with the thiol-azo tautomer's extended conjugation). These spectral shifts arise from solvatochromic effects and concentratochromism observed in nonpolar versus polar solvents.

Physical and chemical properties

Physical properties

Dithizone is a solid compound that typically appears as a dark to powder or crystalline material. The observed color variations arise from its tautomeric forms. Key physical characteristics include a of 166–170 °C, at which the compound decomposes without a distinct . It exhibits a of approximately 1.36 g/cm³. Dithizone is insoluble in but demonstrates good in solvents, such as (approximately 17 g/L at 20 °C, forming a bright solution), , acetone, and . Under normal laboratory conditions, dithizone remains stable as a solid, though solutions are light-sensitive and require protection from exposure to maintain integrity.

Chemical properties

Dithizone exists predominantly in a tautomeric equilibrium between thione and forms in solution, with the tautomer conferring weakly acidic properties due to the SH group, exhibiting a of approximately 5.0. This acidity arises from the of the , enabling its role in , though the compound remains stable across a wide range in neutral to mildly basic conditions. In terms of behavior, dithizone undergoes oxidation to form dehydrodithizone as the primary stable product, often via air oxidation or electrochemical means, involving cleavage of the S-H bond and subsequent cyclization. of dithizone, typically polarographic or electrochemical, yields derivatives through cleavage of the azo linkage, rendering the process reversible under controlled conditions. Dithizone demonstrates photochemical instability, exhibiting photochromism in nonpolar solvents such as , where exposure to visible light induces a color shift from green to red due to cis-trans around the azo bond. This transient change is reversible in the dark, highlighting its sensitivity to light in analytical applications. of dithizone occurs above 168 °C, proceeding in multiple steps to release carbon, , and oxides as primary gaseous products, along with fragmentation into and related moieties. The process is exothermic, with significant mass loss observed between 100 °C and 600 °C under inert atmospheres. Under solvolytic conditions, dithizone hydrolyzes in strong acids such as concentrated to regenerate diphenylthiocarbazide, the precursor in its synthesis, via reversal of the step. As a , dithizone functions as a bidentate chelator, binding metals through its atom from the group and from the moiety, forming stable five-membered rings with high affinity for soft metal ions like mercury and lead.

Synthesis

Historical preparation

Dithizone was first synthesized in 1878 by the German chemist during his investigations into derivatives, via the reaction of with to form diphenylthiocarbazide as an intermediate. This compound, upon treatment with a base such as , undergoes rearrangement to yield dithizone as a green solid. In the , significant developments occurred when chemist explored dithizone's properties and recognized its potential as an analytical reagent for detection in 1925. Initial historical preparations often resulted in impure green solids due to incomplete reactions and byproduct formation. These early synthetic routes suffered from low yields, typically ranging from 30% to 50%, primarily owing to side involving over-thiolation or decomposition of intermediates. Purification was achieved through recrystallization from , which helped isolate the desired green crystalline product, though multiple iterations were often required to attain analytical purity. The seminal reference for dithizone's remains 1878 publication in Justus Liebig's Annalen der Chemie on of with .

Modern synthesis methods

A common modern synthesis route for dithizone (diphenylthiocarbazone) begins with the preparation of diphenylthiocarbazide from and . is dissolved in and reacted with at room temperature to form the phenylhydrazine salt of β-phenyldithiocarbazic acid in 96–98% yield; this salt is then pyrolyzed in at 96–98°C to yield crude diphenylthiocarbazide (60–75% based on ). The crude diphenylthiocarbazide is refluxed with in for 5 minutes, cooled, and acidified with to precipitate the product, which is further purified by dissolution in , re-acidification, and washing to remove sulfates. In the , the overall yield of pure dithizone is approximately 50–64% based on , with the product obtained as a green solid decomposing at 165–169°C. A more recent industrial-scale approach, detailed in a , modifies the route for enhanced safety and reduced toxicity by replacing and with as the solvent and using and instead of and for acidification. (400 g) is mixed with (1600 g) and (180 g) at 20–25°C, followed by to release and , yielding the intermediate; this is then oxidized in methanolic , precipitated with , redissolved in with added as an (0.0001–0.0004 ratio to crude), and re-precipitated, affording 80–100 g of purified dithizone after drying at 50–55°C. This minimizes corrosive byproducts and environmental hazards, achieving higher product purity with lower ash content. Purification of crude dithizone typically involves recrystallization from or a -ethanol mixture to obtain analytically pure material, often confirmed by () on with as eluent or () for impurity profiling. For scale-up in industrial preparation, phosphorus-containing (used in some older methods) are avoided due to concerns, with batch yields reaching 80–90% through optimized solvent systems and controlled oxidation conditions.

Analytical applications

Principle of metal chelation

Dithizone functions as a bidentate chelating agent, binding metal ions primarily through its deprotonated thiolate sulfur atom and the azo nitrogen atom, which together form a stable five-membered chelate ring. This coordination mode is facilitated by the ligand's structure, where the thiol group (-SH) loses a proton to become a soft donor, enhancing its affinity for transition and heavy metals. The resulting complexes are typically neutral and highly stable due to the chelate effect, which increases the thermodynamic stability compared to monodentate ligands. The of dithizone-metal complexes varies with the , commonly adopting 1:1 or 1:2 (metal:) ratios. For instance, the mercury(II) complex adopts a 1:2 , formulated as (Dz)2, where Dz denotes the deprotonated dithizonate anion, resulting in a characteristic red-colored soluble in media. Similar 1:2 complexes form with other divalent metals like lead and , while trivalent metals such as may form 1:3 under specific conditions. Dithizone exhibits pronounced selectivity for soft metal ions, including Hg²⁺, Pb²⁺, Cd²⁺, and Bi³⁺, aligning with Pearson's Hard-Soft Acid-Base (; the soft sulfur donor atom preferentially interacts with soft acid centers of these metals over harder ones like or alkaline earth ions. This selectivity is quantified by high formation constants, such as log β = 12.5 for the lead(II)-dithizone complex and even higher values for mercury(II) (log β ≈ 40), reflecting exceptional stability in mildly acidic to neutral ranges. The general complexation reaction can be represented as: \ce{M^{2+} + 2 HDz ⇌ M(Dz)2 + 2 H+} where HDz is the protonated form of dithizone, and the equilibrium shifts toward complex formation in non-aqueous environments. The intense colors of these complexes originate from ligand-to-metal charge transfer (LMCT) transitions, where electrons are excited from the ligand's π-orbitals to the metal's d-orbitals, producing absorption bands in the visible spectrum. Representative examples include the red hue of the mercury complex (λmax ≈ 490 nm), orange for lead (λmax ≈ 520 nm), and violet for bismuth (λmax ≈ 510 nm), enabling sensitive colorimetric detection. Additionally, the lipophilicity imparted by the phenyl groups in dithizone allows the neutral complexes to partition readily into organic solvents like carbon tetrachloride from aqueous phases, facilitating extraction-based separations.

Specific detection methods

Dithizone is widely employed in colorimetric assays for the quantitative determination of , particularly lead, through the formation of a cherry-red metal-dithizonate complex that is extracted into an organic solvent such as . In this procedure, an acidified aqueous sample is adjusted to an alkaline and mixed with a dithizone solution in , allowing the selective of the colored complex, which is then measured spectrophotometrically at approximately 520 nm. The method achieves detection limits around 0.01 mg/L (0.01 ppm) for lead, making it suitable for trace-level analysis in environmental samples. A titration-based approach using dithizone serves as a limit test for mercury in pharmaceutical preparations, as outlined in the . Here, the sample is treated under acidic conditions to form the orange-red mercury-dithizonate complex, which is then titrated with a standardized dithizone solution in until a persistent color indicates the endpoint, allowing back-titration if excess dithizone is added. This method is particularly valued for its simplicity in assessing compliance with mercury impurity limits, typically below 3 . For qualitative screening, spot tests utilize or plates impregnated with dithizone, where a sample produces a characteristic color change upon contact with metal ions, such as a red spot for mercury. This rapid technique enables on-site detection of at concentrations as low as 0.1 without sophisticated instrumentation. The efficacy of dithizone-based detection is highly -dependent, with optimal complex formation occurring between 2 and 10 depending on the target metal; for instance, lead extraction is favored at pH 10–11.5, while mercury responds at lower pH values around 2. Selectivity is enhanced by masking agents like citrate or , which complex interfering ions—for example, citrate prevents interference in lead assays, allowing separation of lead from . Interferences from metals such as , tin, or , which also form colored complexes, are mitigated through sequential extractions, adjustments, or cyanide masking to bind non-target ions without affecting the primary complex. These methods find applications in analyzing trace in water, food, and pharmaceuticals, providing reliable quantification in complex matrices. Historically, dithizone-based spot tests were used for lead detection in , involving acid or ashing followed by color observation to assess compliance with safety limits. This approach contributed to early benchmarks for environmental and consumer product testing before atomic absorption techniques became predominant. Recent advances have enhanced dithizone's analytical utility through integration with and portable formats. For example, paper-based dipstick test strips impregnated with dithizone enable rapid, on-site colorimetric detection of lead and at trace levels (down to 20 ppb) without , suitable for as of 2025. Additionally, nanocellulose-stabilized dithizone emulsions improve stability and sensitivity for sensing in aqueous solutions, addressing traditional issues.

Biological and medical uses

In pancreatic islet staining

Dithizone, also known as diphenylthiocarbazone (DTZ), is used in diabetes research to visualize and assess , particularly beta cells, through selective staining. This technique helps identify and quantify islets during isolation for transplantation in therapy, aiding in the evaluation of preparation purity and quality without invasive methods. The staining mechanism involves dithizone chelating ions (Zn²⁺) abundant in insulin granules of s, forming a stable complex that gives s a under visible . This is specific to the zinc-rich in secretory granules, where stabilizes insulin hexamers. Alpha cells, lacking significant zinc-insulin storage, remain unstained, allowing differentiation within the . The technique also indicates viability, as dead or compromised cells lose or membrane integrity, showing reduced staining when combined with dyes like . The standard procedure uses a 50 µM dithizone solution in a buffered medium such as (HBSS) with DMSO as a , exposing isolated for 5–10 minutes at . Islets turn red quickly, enabling visual assessment under a light microscope for counting and purity evaluation, often in islet equivalents (IEQ). This method has been part of protocols like the Edmonton protocol since the early 2000s, standardizing islet assessment for clinical transplants in to ensure viable mass. Dithizone for was first reported in 1964, building on earlier zinc-detection applications from the mid-20th century, and remains integral to islet isolation. Advantages include low toxicity at used concentrations for without major cell damage, speed for real-time processing, and potential for quantitative analysis via to measure islet volume and purity. As of 2025, it continues as a standard tool in research on cell-derived islets, though emerging fluorescent alternatives are being explored. Limitations include fading of the stain over time, preventing prolonged observation, unsuitability for imaging due to direct tissue exposure needs, and overestimation of purity by 20–30% compared to , necessitating complementary methods.

As a chelating agent

Dithizone has been used as a chelating agent in the management of poisoning, targeting metals such as , mercury, and lead by forming lipophilic complexes to aid excretion. Explored for therapeutic applications from the mid-20th century, it was administered orally or intravenously to bind metal ions in and tissues, promoting elimination via or as an alternative to (BAL) in select cases. Due to poor solubility, it was formulated in vehicles like glucose solutions or as a to improve . In clinical practice, for , dithizone was given at 10 mg/kg orally twice daily, mixed with 10 ml of 10% glucose solution, for up to 5 days, though its diabetogenic effects restricted adoption. For mercury intoxication, it enhanced urinary excretion by forming excretable complexes. For lead, it was used historically but showed variable efficacy. Although effective in early protocols, dithizone is no longer used clinically as of the early , having been supplanted by safer agents like meso-2,3-dimercaptosuccinic acid (DMSA) due to its toxicity and inconsistent results. In research, dithizone studies mechanisms by binding and depleting from tissues to evaluate . In rats, it induces experimental by depleting from pancreatic cells, causing beta-cell and , modeling . This zinc-chelating action aids investigation of metal , but human therapeutic use is restricted and obsolete in standard care.

Safety and environmental considerations

Toxicity profile

Dithizone exhibits moderate upon ingestion, with an oral LD50 in rats reported as greater than 500 mg/kg. Exposure to dithizone can cause gastrointestinal symptoms including , , and due to of mucous membranes in the , , , and . Inhalation of dithizone dust may lead to respiratory , while skin contact results in and potential , though dermal absorption is minimal. Chronic exposure to dithizone in induces beta-cell toxicity in the , leading to selective destruction of insulin-producing cells, , and mellitus-like conditions. Dithizone is not classified as a by major agencies such as the International Agency for Research on Cancer (IARC). The primary mechanism of dithizone's toxicity involves of ions, which are abundant in pancreatic cells; this disrupts zinc-dependent processes essential for insulin synthesis and secretion, resulting in beta-cell damage. Dithizone also forms complexes with other essential metals such as , potentially contributing to deficiencies that may manifest as in prolonged exposures. Under the Globally Harmonized System (GHS), dithizone is classified as causing skin irritation (H315), serious eye irritation (H319), and may cause respiratory irritation (H335); no specific OSHA (PEL) has been established for dithizone.

Handling and disposal

Dithizone, being light-sensitive, must be stored in amber bottles to prevent , maintained under an inert atmosphere to minimize oxidation, and kept in a cool, dry environment to avoid moisture absorption. Under these conditions, the powder exhibits a of 1 year. Safe handling requires the use of , including gloves, safety goggles, and face protection, with respiratory protection (such as a P2 filter) recommended when dust generation is possible. Operations involving dithizone should be conducted in a well-ventilated area or to prevent of dust or vapors. In the event of a spill, evacuate the area, ensure adequate ventilation, and absorb the material using an inert absorbent like or to avoid formation. Neutralize any residues with a mild if necessary, collect the absorbed material, and dispose of it as in sealed, labeled containers. Disposal of dithizone and contaminated materials should involve in a permitted facility or treatment with oxidizing agents to ensure complete destruction, in compliance with EPA (RCRA) regulations for hazardous wastes, given its role as a chelator. Dithizone is subject to the EU REACH Regulation (EC) No 1907/2006, with safety data sheets (SDS) required for proper labeling, handling, and transport to ensure regulatory compliance.

References

  1. [1]
    Cas 60-10-6,Dithizone | lookchem
    Dithizone, also known as Diphenylthiocarbazone, is an organosulfur compound that acts as a chelating agent, forming stable complexes with various metals ...
  2. [2]
  3. [3]
    Dithizone - Organic Syntheses Procedure
    The crude diphenylthiocarbazide is added to a solution of 60 g. of potassium hydroxide in 600 ml. of methanol in a 1-l. round-bottomed flask.Missing: properties | Show results with:properties
  4. [4]
    An Improved Method for the Preparation of Dithizone ...
    Karel G. von Eschwege. Synthesis and kinetics of electronically altered photochromic dithizonatophenylmercury(II) complexes.
  5. [5]
    Dithizone - an overview | ScienceDirect Topics
    Dithizone is defined as a chemical reagent used for the extraction and detection of mercury in solutions, characterized by its ability to form colored complexes ...
  6. [6]
  7. [7]
    [PDF] Dithizone, ACS, 85+% - Thermo Fisher Scientific
    IUPAC Name: 3-(phenylamino)-1-(phenylimino)thiourea. Molecular Formula: C13H12N4S. Molecular Weight: 256.33. InChI Key: UOFGSWVZMUXXIY-UHFFFAOYSA-N. SMILES: S=C ...
  8. [8]
    Dithizone - CAS Common Chemistry
    Molecular Formula. C13H12N4S. Molecular Mass. 256.33. Discover more in SciFinder. Cite this Page. Dithizone. CAS Common Chemistry. CAS, a division of the ...Missing: weight IUPAC
  9. [9]
  10. [10]
    Showing metabocard for Dithizone (HMDB0251496)
    Sep 11, 2021 · SMILES for HMDB0251496 (Dithizone). S=C(NNC1=CC=CC=C1)N=NC1=CC=CC=C1 ... Monoisotopic Molecular Weight, 256.078267576. IUPAC Name, 3 ...
  11. [11]
    Dithizone, ACS, 85+% | Fisher Scientific
    Chemical Identifiers ; MDL Number, MFCD00003025 ; Synonym, dithizone, dithizon, ditizon, carbazone, diphenylthio, usaf ek-3092, diazenecarbothioic acid, phenyl-, ...
  12. [12]
    Dithizone | C13H12N4S - ChemSpider
    ChemSpider record containing structure, synonyms, properties, vendors and database links for Dithizone, 60-10-6, UOFGSWVZMUXXIY-BMRADRMJSA-N.Missing: PubChem CAS
  13. [13]
    (Phenylazo)thioformic acid 2-phenylhydrazide - PubChem - NIH
    2.4.1 Depositor-Supplied Synonyms · (Phenylazo)thioformic acid 2-phenylhydrazide · DTXSID0058770 · RefChem:1051024 · DTXCID6042737 · DITHIZONE · 60-10-6 ...<|control11|><|separator|>
  14. [14]
  15. [15]
    Seven Chromisms Associated with Dithizone - ACS Publications
    Hydrogen bonding to substituent atoms, O and S, is suggested to facilitate proton transfer during tautomerization reactions, thus the more pronounced ...Missing: lengths | Show results with:lengths
  16. [16]
    NMR-Spectroscopic Investigation of E/Z-Isomerism in Substituted ...
    NMR-spectroscopic investigations of substituted dithiocarbacinic acid derivatives show the existence of configurational isomers relative to the C=N double bond, ...
  17. [17]
    (1,5-Diphenylthiocarbazonato-κS)trimethyltin(IV) - PMC
    Bond lengths along the ligand backbone are neither typically single nor double bond in character. However, the N3—N4 bond length of 1.267 (9) Å and the N1—C1 ...<|separator|>
  18. [18]
    Dithizone, 98% 25 g | Buy Online | thermofisher.com
    6–10 day deliverySpecifications Specification Sheet ; Appearance (Color)Dark purple to black ; lambda-max (UV-Vis)595-610nm (in Chloroform) ; FormPowder ; Assay from Supplier's CofA ...
  19. [19]
    Buy Dithizone - Chelating Agent for Heavy Metal Ion Detection at ...
    Dithizone ... Dark green crystalline solid. Shape: Powder, other. Solubility: Slightly soluble in alcohol and insoluble in water. Physical Form: Dark green powder ...
  20. [20]
    None
    ### Physical and Chemical Properties of Dithizone (Sigma-Aldrich Product #43820)
  21. [21]
    Dithizone 98% AR
    ₹4,730.00With a refractive rate of 1.558 and a density of 1.362 g/cm3, this product is insoluble in water but soluble in organic solvents. It is stored in a cool, dry, ...
  22. [22]
    Durable Nanocellulose-Stabilized Emulsions of Dithizone ...
    Feb 23, 2023 · Overall, one DTZ molecule is closely surrounded, with intermolecular distances of 4 Å or less, by 22 chloroform molecules in its symmetric ...<|control11|><|separator|>
  23. [23]
    Dithizone, 98% 10 g | Buy Online | Thermo Scientific Alfa Aesar
    Solubility Soluble in ethanol, chloroform, dimethylsulfoxide, and pyridine. Insoluble in water. Notes Incompatible with strong oxidizing agents ...
  24. [24]
  25. [25]
    [PDF] Detection of heavy metals with dithizone- cyclodextrin complex
    In most experiments dithizone is dissolved in chloroform that results in a green coloured solution. Figure 1: Chemical composition of dithizone in keto- ...<|control11|><|separator|>
  26. [26]
    Dithizone | 60-10-6 - ChemicalBook
    Sep 25, 2025 · Dithizone is used to assess the purity of human pancreatic islet preparations used for transplantation into patients with type 1 diabetes.
  27. [27]
    Part I.The reduction of dithizone in aqueous solutions - ScienceDirect
    The reaction is reversible and dithizone can be determined polarographically in the range 10-3–10-5M.
  28. [28]
    A thermal analysis study of dithizone and ... - SciELO Brasil
    2(a), show thermal stability up to 100oC and that the thermal decomposition occurs in three consecutive steps between 100oC and 600oC.
  29. [29]
    [PDF] Studies with Dithizone - University of Cape Town
    X-ray crystallographic studies have shown that the C - Tl - C bond ... Hence, no direct comparisons between (Tl - S) and (Tl - N) bond lengths can be made.<|separator|>
  30. [30]
    CN1970537A - Process for manufacturing diphenylthiocarbazone
    The invention discloses a making method of modified diphenylthiocarbazone based on phenylhydrazine and carbon bisulphide as raw material, which comprises ...
  31. [31]
    X-Ray Dosimetry by Radiolysis of Some Organic Solutions - jstor
    Dithizone was purified by recrystallization from a mixture of chloroform and ethanol and dissolved in chloroform and carbon tetrachloride, respectively, to.
  32. [32]
    A structural study of dithizone coordination chemistry - RSC Publishing
    Here we give insight into the binary complexes of dithizone, which contain two different metal ions, and the secondary complexes with Cu(II).
  33. [33]
    Stability constants of some metal dithizonates - ScienceDirect.com
    The stability constants for dithizone complexes with Hg2+ and Pb2+ are 2.0 × 1040 and 1.4 × 1014, respectively [22].
  34. [34]
    [PDF] 3500-Pb LEAD* 3500-Pb A. Introduction 3500-Pb B. Dithizone Method
    8.5 to 9.5) dithizone forms colored complexes with bismuth, stannous tin, and monovalent thallium. In strongly ammoniacal citrate-cyanide solution (pH 10 to ...
  35. [35]
    Detection Techniques for Lead Ions in Water: A Review - PMC
    Apr 20, 2023 · As the traditional dithizone color method consumes a large test dose, large waste liquid displacement, the masking agent used is highly toxic, ...
  36. [36]
    General Chapters: <261> MERCURY - USP29-NF24
    DITHIZONE TITRANT— Dilute 30.0 mL of Dithizone Stock Solution with chloroform to 100.0 mL. This solution contains approximately 12 mg of dithizone per L.
  37. [37]
    Screening for Mercury in Aqueous Environmental Samples and ...
    Nov 1, 2007 · R F value and color of the spot of different metal dithizone complexes upon running on the TLC plate. image. Detection of Mercury in Urine ...
  38. [38]
    A Rapid Spectrophotometric Method for the Determination of Trace ...
    Feb 10, 2007 · Metal-dithizone complexes are water insoluble and thus their ... Pb(II); the stoichiometric composition of the chelate is 1:2 (Pb:dithizone).
  39. [39]
    [PDF] Methods for measuring lead concentrations in paint films
    Laboratory analysis of paint films for lead using the ASTM standard procedure D 3335. Test Method for LowConcentrations of Lead. Cadmium and. Cobalt in Paint ...
  40. [40]
    Dithizone - an overview | ScienceDirect Topics
    Dithizone (diphenylthiocarbazone, DTZ) is the commonly accepted technique employed currently to assess the purity of islet preparations.Missing: thiocarbazone | Show results with:thiocarbazone
  41. [41]
    In vitro staining of islets of Langerhans for fluorescence ... - PubMed
    The chelating agent dithizone (DTZ) produces bright red staining of islets by topical application in vitro. Further studies showed that dithizone-stained ...Missing: zinc insulin granules UV
  42. [42]
    Enhancing the Functionality of Immunoisolated Human SC-βeta Cell ...
    DTZ is a red dye that binds zinc within mature insulin granules, and the density of staining can be associated with intracellular insulin content and islet ...
  43. [43]
    Specificity and viability of isolated islets. (A) Islets stained with...
    In double staining with trypan blue and dithizone simultaneously healthy islets stained reddish-brown with dithizone while the dead and membrane-compromised ...Missing: procedure limitations
  44. [44]
    [PDF] a simple method of staining fresh and cultured islets
    In this study, we describe the use of the zinc-binding substance diphenylthiocarbazone (dithizone, [DTZ]*) to stain islets in vitro and demonstrate that this ...Missing: advantages limitations
  45. [45]
    Islet Graft Assessment in the Edmonton Protocol | Diabetes
    Dec 1, 2004 · This study reports on the assessment of 83 human islet grafts transplanted using the Edmonton Protocol since 1999. Cellular composition, as ...
  46. [46]
    Islet Assessment for Transplantation - PMC - NIH
    ... dithizone (DTZ) staining to determine the total volume of islet tissue and its purity. This method has advantages and limitations (See Table 2A) that are ...
  47. [47]
    Quantitative analysis of cell composition and purity of human ...
    This study used both light microscopy (LM) and electron microscopy (EM) to characterize 33 islet preparations used for clinical transplants.Missing: historical | Show results with:historical
  48. [48]
    Thallium Use, Toxicity, and Detoxification Therapy: An Overview
    Although being a highly toxic element, thallium has been studied to a much lesser degree than other toxic elements such as lead, cadmium, or mercury [31,32].
  49. [49]
  50. [50]
    (PDF) Management of Thallium Poisoning - ResearchGate
    Aug 6, 2025 · The literature pertinent to the use of dithizone and diethyldithiocarbamate in the treatment of thallium poisoning is reviewed.
  51. [51]
    Chelating Agents in Medicine: Journal of Toxicology
    Sep 25, 2008 · This particular review deals with the toxic effects of this dose-response curve and the use of chelating agents to remove execessive quantities of metal ions.<|control11|><|separator|>
  52. [52]
    Thallium Toxicity - StatPearls - NCBI Bookshelf
    Oct 9, 2024 · The typical dose is 250 mg/kg per day in 2 or 4 divided doses. A definitive end point of therapy has not been established.Missing: dithizone | Show results with:dithizone
  53. [53]
    Animal models for induction of diabetes and its complications - PMC
    Aug 29, 2023 · We conducted a systematic review to find various animal models to induce diabetes and also the suitable methods in various diabetic complications.
  54. [54]
    A change in the zinc ion concentration reflects the maturation of ...
    Dec 10, 2019 · Dithizone staining is used to evaluate IPCs by detecting zinc. We hypothesised that zinc ion (Zn2+) dynamics reflect the IPC maturation status.Missing: lose | Show results with:lose
  55. [55]
    [PDF] Safety Data Sheet - Fisher Scientific
    Mar 19, 2015 · Excessive heat. Incompatible materials:Strong oxidizing agents. Hazardous decomposition products:Carbon oxides.Nitrogen oxides.Sulfur oxides.
  56. [56]
    Mechanism of action of diabetogenic zinc-chelating agents. Model ...
    Using model systems, we have studied the properties of a number of zinc-chelating agents which are known to cause diabetes in laboratory animals.Missing: toxicity copper
  57. [57]
    Dithizone - PubChem - NIH
    Chelating agent used for heavy metal poisoning and assay. It causes diabetes. Medical Subject Headings (MeSH) ...
  58. [58]
  59. [59]
    Buy Dithizone Powder at Best Price, Industrial Grade with 95%
    Dithizone Powder is an industrial grade powder with a purity level ranging from 95% to 99%. This industrial lab chemical has a shelf life of 12 months.
  60. [60]
    [PDF] SAFETY DATA SHEET - Fisher Scientific
    Mar 30, 2024 · Avoid ingestion and inhalation. ... Skin and body protection. Wear appropriate protective gloves and clothing to prevent skin exposure.Missing: routes absorption
  61. [61]
    [PDF] Dithizone - Santa Cruz Biotechnology
    TOXICITY. IRRITATION. Intraperitoneal (mouse) LD50: 200 mg/kg. Nil Reported ... Shipping Name: TOXIC SOLID, ORGANIC, N.O.S. *(CONTAINS DITHIZONE). Maritime ...
  62. [62]
    Anaerobic Mercury Methylation and Demethylation by Geobacter ...
    The discovery that slurries of anoxic sediments could also degrade MeHg by forming CO2 and Hg(II) revealed another mechanism for demethylation, possibly as ...