First-derivative spectrophotometric and LC determination of cefuroxime andcefadroxil in urine

Two methods are presented for the determination of cefuroxime and cefadroxi l in human urine using first (D-1) derivative spectrophotometry and high-pe rformance liquid chromatography. Cefuroxime and cefadroxil were deter mined by measurement of their first-derivative amplitude in 0.1 N sodium hydroxi de at 292.5 and 267.3 nm, respectively in the concentration range of 2-10 m u g ml(-1) for each drug. The HPLC method depends upon using a LiChrospher 100 RP-18 (5 mu m) column at ambient temperature for cefuroxime and 35 degr ees C for cefadroxil with mobile phases consisting of water-acetonitrile-ac etic acid (85:15:0.1 v/v) at a flow rate of 1.5 ml min(-1) for cefuroxime; and 0.02 M potassium dihydrogen phosphate-acetonitrile (95:5 v/v) containin g 0.003% (w/v) hexanesulphonic acid sodium salt and adjusted to apparent pH 3 with phosphoric acid at a flow rate of 2 mi min(-1) for cefadroxil. Quan titation was achieved with UV detection at 275 and 260 nm for cefuroxime an d cefadroxil, respectively, based on peak area with linear calibration curv es at the concentration ranges of 2-10 mu g ml(-1) for cefuroxime and 5-20 mu g ml(-1) for cefadroxil. The proposed methods were applied to the determ ination of dissolution rate for tablets and capsules containing each drug. The urinary excretion patterns as the cumulative amounts excreted have been calculated for each drug using the proposed methods. (C) 2000 Elsevier Sci ence B.V. All rights reserved.