FLOW-INJECTION CHEMILUMINESCENCE DETERMINATION OF MEDAZEPAM

A new flow injection chemiluminescence method for the assay of medazep am is explored. The method involves the use of permanganate in sulfuri c acid for the oxidation of medazepam with the emission of chemilumine scence detected by a photomultiplier tube. A simplex procedure was emp loyed for optimising the conditions for high sensitivity detection, wh ich were found to be 1.03 x 10(-3) mol L-1 permanganate, 0.153 mol L-1 sulfuric acid and 3.43 mt min(-1) flow rate. The linear calibration r ange was 3.7 x 10(-5) to 1.7 x 10(-3) mol L-1. The detection limit (3 sigma) and the sample throughput were 1.85 x 10(-5) mol L-1 and 100 pe r hour, respectively. The relative standard deviation for 5 replicate determinations of 1.9 x 10(-4) mol L-1 medazepam was 0.15%. Common exc ipients (starch, glucose, maltose, lactose) used in pharmaceutical pre parations had no effect.