Oxidized haematoxylin,a new reagent for the spectrophotometric determination of penicillins and cephalosporins

Haematoxylin—Chloramine-T in phosphate buffer (pH 7.0) is proposed as a new reagent for spectrophotometric determination of penicillins and cephalosporins in pure samples and pharmaceutical preparations. The method is based on acid hydrolysis of penicillins and cephalosporins with 5M HCl and subsequent treatment with oxidized haematoxylin. The resulting colour exhibits maximum absorption at 555 nm.