Determination of Paracetamol by a Flow Injection-Spectrophotometric Method

Abstract
A flow injection-spectrophotometric determination of paracetamol is reported. The procedure is based on the oxidation of the analyte with potassium hexacyanoferrate (III) and reaction of the N-(hydroxyphenyl)-p-benzoquinonimine produced with phenol; both reactions are carried out at 80 × 1°C and in aqueous ammoniacal solution. Concentrations of paracetamol in 0.25-30 ppm range are determined; relative standard deviations are 0.4% (n=40).Injection rate 26 samples/h.The influence of foreign species and the determination of paracetamol in several pharmaceutical formulations are also reported.