Differential pulse polarographic determination of cephalexin based on the catalytic pre-wave of nickel(II)

Abstract

A nickel-catalytic pre-peak at −0.72 V vs. Ag/AgCl, is caused by cephalexin in sodium acetate (pH 8.3) medium. It is used to determine 2.4 × 10 −7–6 × 10 −6 M cephalexin; the relative standard deviation is 4% for 0.88 μg ml −1 cephalexin. Other cephalosporins behave similarity; some amino acids can be tolerated in moderate amounts.