Spectrophotometric Determination of Promethazine Hydrochloride Based on Inhibition of Hemoglobin

Abstract

A highly sensitive and simple catalytic spectrophotometric method for the determination of promethazine hydrochloride based on inhibitory effect of promethazine hydrochloride on the hemoglobin-catalyzed the reaction of H₂O₂ and acid chrome blue K (ACBK) was developed. The concentration of promethazine hydrochloride is linear with the percentage inhibition (I %) of system under the optimal experimental conditions. The calibration graph is linear in range 6.23 × 10^-8 to 1.56 × 10^-5 mol L^-1 with the detection limit of 9.32 × 10^-10 mol L^-1. This method can be used for the determination of promethazine hydrochloride in tablets and injection solution of promethazine hydrochloride with satisfactory results.