Spectrophotometric Determination for Benzodiazepine Drμgs (Clonazepam and Nitrazepam) in Pure and Pharmaceuticals Preparation

摘要

Depending oh the oxidative coupling reaction as a rapid and selective spectrophotometric method, reduced clonazepam and nitrazepam drμgs were evaluated by using potassium bromate as oxidation agent for these drμgs and phenylephrine hydrochloride as a new chromogenic reagent to give red coloured products for clonazepam and nitrazepam at a maximum absorption of 491 and 488 nm, respectively. The linear ranges was 2-60 μg mL~(-1) and 5-90 μg mL~(-1) while the molar absorptivity are 3.157 x 103 L mol~(-1) cm~(-1) and 3.825 x 10~3 L mol~(-1) cm~(-1) and their detection limits are 0.141 μg mL~(-1) and 0.104 μg mL~(-1) , respectively for clonazepam and nitrazepam. The proposed methods did not require any temperature control and also not affected by foreign excipients and henceforth successfully applied to determine clonazepam and nitrazepam in pharmaceutical preparations.