Simple chemiluminescence determination of pilocarpine in pharmaceuticals and human serum

A new method using flow injection analysis (FIA) and chemiluminescence (CL) detection has been developed for the rapid, simple and precise determination of pilocarpine hydrochloride (PH). The method is based on the CL reaction of PH with tris(1, 10 phenanthroline)ruthenium(II), [Ru(phen)32+], and Ce(IV) in sulfuric acid medium. Effects of chemical variables were investigated using a central composite design (CCD) and the response surface methodology (RSM). Under optimum conditions, the CL intensity was proportional to the concentration of the drug in solution over the range 0.12-40.00 µg mL-1. The limit of detection (S/N = 3) was 34 ng mL-1. The method was applied successfully to the determination of PH in pharmaceutical formulations and spiked human serum. The relative standard deviation for determination of 7 replicates at a level of 1.5 µg mL-1 of PH was 0.6%. The minimum sampling rate was 70 samples per hour.