| Field | Specification |
|---|---|
| Alternative names | 2,2-Diphenyl-1-picrylhydrazyl |
| CAS no. | |
| Applications | |
| Molecular weight | |
| Molecular formula | C18H12N5O6 |
| Purity | |
| SMILES | |
| Form | Solid |
| Storage | |
| Shipping | |
| Catalog no. (Mfr.) | |
| Main SKU |
Compound Overview
DPPH, also known as 2,2-Diphenyl-1-picrylhydrazyl, is a stable free radical that can be used to measure the radical scavenging activity of antioxidants. Its odd nitrogen electron is reduced to the corresponding hydrazine upon receiving a hydrogen atom from an antioxidant, and the DPPH method can be applied in both aqueous and nonpolar organic solvents to examine hydrophilic and lipophilic antioxidants alike[1]. It is supplied as a brown to black solid (C18H12N5O6, MW 394.32) at 98.77% purity.
Physical & Chemical Properties
| CAS Number | 1898-66-4 |
|---|---|
| Molecular Formula | C18H12N5O6 |
| Molecular Weight | 394.32 g/mol |
| Purity | 98.77% |
| Appearance | Solid |
| Color | Brown to black |
| SMILES | O=[N+](C1=C([N]N(C2=CC=CC=C2)C3=CC=CC=C3)C([N+]([O-])=O)=CC([N+]([O-])=O)=C1)[O-] |
| Signaling Pathway | Immunology/Inflammation; NF-κB; Metabolic Enzyme/Protease |
| Solubility | In Vitro: DMSO: 25 mg/mL (63.40 mM; Requires sonication; Hygroscopic DMSO has a significant impact on the solubility of product, please use newly opened DMSO) |
| Storage | -20°C, protect from light. In solvent: -80°C, 6 months; -20°C, 1 month (protect from light). |
| Shipping | Room temperature in continental US; may vary elsewhere. |
Literature Cited
Sources cited in this description and in the In Vitro & In Vivo Data tab. Peer-reviewed publications that used this product are listed under References.
Safety
For Research Use Only. Not for use in diagnostic or therapeutic procedures, and not for human or veterinary use. Handle in accordance with the Safety Data Sheet and your institution's chemical hygiene plan.
In Vitro
| Solvent | Solubility | Notes |
|---|---|---|
| DMSO | 25 mg/mL (63.40 mM) | requires sonication; use freshly opened DMSO (absorbed moisture lowers solubility) |
Aliquot the stock solution and store it at -80°C (up to 6 months) or -20°C (up to 1 month); protect from light; avoid repeated freeze-thaw cycles.
Data provided by the manufacturer.
In Vitro
Owing to its odd electron, DPPH has a strong absorption band at 517 nm, and its solution takes on a deep violet colour; the absorption disappears once the electron is paired. Decolorization of this kind is stoichiometric relative to how many electrons are taken up. Solutions in alcohol at 0.5 mM are densely colored, and at that concentration absorption follows the Lambert-Beer law across the useful range[1]. As a rapid, simple, inexpensive and widely used method, the DPPH assay measures how well compounds serve as free radical scavengers or hydrogen donors, and it also evaluates the antioxidant activity of foods. Antioxidants in complex biological systems can be quantified with it as well, in solid or liquid samples. The method is easy to apply for gauging overall antioxidant capacity and free radical scavenging activity of fruit and vegetable juice. With this assay, antioxidant properties have been investigated successfully in wheat grain and bran, vegetables, conjugated linoleic acids and herbs, as well as edible seed oils and flours, in several different solvent systems, among them ethanol, aqueous acetone, methanol, aqueous alcohol and benzene. Cysteine, glutathione, ascorbic acid, tocopherol and polyhydroxy aromatic compounds can be assayed for antioxidant activity this convenient way, as can olive oil, fruits, juices and wines[1].
Data provided by the manufacturer. Numbered citations refer to the Literature Cited list in the product description.
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- Add-on labels & handles: D/¹³C/¹⁵N isotopes (LC-MS/internal standards), azide/alkyne or other functional handles for conjugation
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