Description
2,6-Dichlorophenol Indophenol (often referred to as DCPIP or DCIP) is a synthetic, water-soluble redox indicator and dye, widely used in analytical, biochemical, and food chemistry.
Chemical Properties
Chemical name: 2,6-Dichlorophenolindophenol (sodium salt often used in labs)
Molecular formula (sodium salt):
C
12
H
6
Cl
2
NNaO
2
C
12
H
6
Cl
2
NNaO
2
Molecular weight (sodium salt): 290.08 g/mol
CAS Number: 620-45-1 (sodium salt)
Appearance: Dark blue to dark green powder or crystals; dark green (sodium salt dihydrate)
Solubility: Water (30 g/L), alcohol (20 g/L)
Purity (AR/ACS): 98–106% (commercial, for analysis grade)
Major Uses
Redox Indicator: Exhibits a blue color when oxidized and turns colorless (or pale yellow) when reduced.
Vitamin C (Ascorbic Acid) Analysis: Commonly used in titration methods for quantitative estimation of ascorbic acid in food, juice, and pharmaceuticals. When ascorbic acid reduces DCPIP, the solution becomes colorless, marking the endpoint.
Respiratory/Photosynthetic Studies: Serves as an artificial electron acceptor in experiments studying the electron transport chain in plants (photosynthesis) and mitochondrial activity.
Biochemical Assays: Used as a substrate to measure enzyme activities, including dehydrogenases and oxidases, and as a reagent in TLC for organic acids and reducing compounds.
Additional Features
pKa: 10.5 (indicative of its behavior as an acid/base)
Shelf life: Typically up to 5 years
Storage: Store at room temperature, protected from light and moisture (the dye is hygroscopic)
Safety
Hazard statements: May cause eye/skin irritation; standard PPE (gloves, eye protection) is recommended.