Determination of clonazepam by flow injection analysis

Abstract

Clonazepam was determined by flow injection analysis using voltammetric (glassy carbon electrode) and spectrophotometric detectors. The sample solution (200 µl of 6.3–31.5 µg ml^–1 and 250 µl of 0.6–31.5 µg ml^–1 for voltammetric and spectrophotometric detection, respectively), was injected into the carrier stream, which was 0.1 M phosphate buffer solution (pH 7.0) containing 10%V/V of methanol. Sampling rates of 120 per hour were achieved, with high reproducibility of measurements (relative standard deviations below 1.1%). The systems were applied to the determination of clonazepam in pharmaceutical formulations and human urine.