HPLC Determination of 2-Nitro-p-benzenediamine in Hair Dyes

HPLC was applied to the determination of 2-nitro-p-benzenediamine in hair dyes. The sample was extracted with mixture of CH3CH2OH-H2O (1+1). The extract was separated on auqo-C18 column by gradient elution with eluants containing A (10 mol·L-1 citric acid +10 mol·L-1 sodium octanesulfonate of pH 2.6) and B (acetonitrile) mixed in the ratio of 75 to 25, and determined with diode array detector at the wavelengths of 410 nm. Linearity range for 2-nitro-p-benzenediamine was found between 2.4-240 mg·L-1, with detection limit (3S/N) of 0.7 mg·L-1. Using sample of hair dyes as matrix, recovery test was made by standard addition method, values of recovery found were in the range of 90.4%-99.4%, with RSD′s (n=6) in the range of 0.35%-3.0%.