Spectrophotometric Determination of Chlordiazepoxide in Pharmaceutical Formulations via Oxidative Coupling Reaction with Phenothiazine

Abstract

A sensitive, precise and reliable indirect spectrophotometric method for the determination of chlordiazepoxide (CDE) in pure and pharmaceutical dosage forms is described. The method is based on oxidative coupling reaction between amino group resulting from acidic decomposition of CDE with phenothiazine in the presence of sodium periodate to produce an intense green soluble dye that is stable and shows a maximum absorption at 602 nm. The calibration plot indicates that Beer's law is obeyed over the concentration range of 0.1−50 µg/mL, with a molar absorptivity of 1×10 4 L/mol cm and correlation coefficient of 0.9994.All the conditions that affecting on the stability and sensitivity of the formed product were studied and optimized and the suggested method was effectively applied for the determination of CDE in commercial dosage forms.

Instrumental Analysis of Chlordiazepoxide in Different Matrices

“…CDZO is chemically known as 7-chloro-2-methylamino5-phenyl-3H-l,4-benzodiazepine-4-oxide (Figure 1), it is a benzodiazepine class sedative and hypnotic medication showing powerful antianxiety effects in humans used to enhance effectively the effect of the neurotransmitter gamma-amino butyric acid (GABA) complex formation [1,4], which strengthens pharmacological activity of benzodiazepine derivatives related not only to their anxiolytic activity, but also to sedative and hypnotic effect, skeletal muscle relaxant and anticonvulsant activity [2].…”