SPECTROPHOTOMETRIC DETERMINATION OF SOME CEPHALOSPORINS USING 2,2'-DIPHENYL-1-PICRYLHYDRAZYL

Document Type : Original Article

Author

Department of Pharmaceutical Chemistry, Faculty of Pharmacy, Al-Azhar University, Assiut, Egypt

Abstract

A spectrophotometric method was developed for the determination of some cephalosporins using 2,2'-diphenyl-1-picrylhydrazyl (DPPH). The latter employed to abstract a hydrogen atom from the drug thereby promoting a process of radical coupling. This results in a reduction of the violet color (520 nm) of DPPH with the formation of the yellow colored 2,2'-diphenyl-1-picrylhydrazine (DPPH). This fading in color of DPPH reagent depends on the concentration of the drug being determined. Beer's law was obeyed in the ranges of; 5-30, 5-25 and 10-30 µg/ml for cephalexin, cefadroxil and cephradine respectively. The validity of the method was tested by carrying out standard addition procedure analyzing the studied drugs in pure form as well as in their pharmaceutical preparations without interference from common additives. The percentage recovery ranged from (97.98-101.21) ±1.15-0.98.