Flow injection chemiluminescence determination of cephalosporins in pharmaceutical preparations using tris(2,2'-bipyridyl)ruthenium (II)-potassium permanganate system

摘要

A flow injection(FT)method using the tris(2,2'-bipyridyl)ruthenium(II)[Ru(bpy)_3~(2+)]-potassium permanganate chemiluminescence(CL)was developed for the rapid and sensitive determination of cephalosporins such as cefoxitin,cefazolin,cephalexin,cefadroxil,cefaclor and cefoperazone.The method is based on the CL reaction of cephalosporins and Ru(bpy)_3~(2+)with potassium permanganate in the presence of perchloric acid,catalyzed by Mn(II).Under the optimum conditions,the calibration curves are linear over the range 0.10-12.0 mugml~(-1)for cefoxitin,0.10-10.0 mugml~(-1)for cefoperazone and 0.10-15.0 mug ml~(-1)for cefazolin,cephalexin,cefadroxil,and cefaclor,respectively.The limits of detection(3sigma)are 0.03 mug ml~(-1)for cefoxitin and cefadroxil,0.06 mug ml~(-1)for cefoperazone and 0.08 mug ml~(-1)for cefazolin,cephalexin and cefaclor,respectively.The method was successfully applied to the determination of cefoxitin,cefazolin,cephalexin and cefadroxil in pharmaceutical formulations with a sample throughput of 90 h~(-1).There were no interference effects from some common excipients used in pharmaceutical preparations.