[Simultaneous spectrophotometric determination of certain beta-lactam antibiotics in rabbit serum using multivariate calibration methods].

Cefuroxime sodium, ceftriaxone sodium, cefotaxime sodium and cefazolin sodium have absorption in ultraviolet region, and their absorption spectra are overlapping. So they can not be determined individually by spectrophotometry without prior separation. In this paper, the chemometric multivariate calibration method was applied to the simultaneous determination of these four compounds in a Britton-Robinson buffer solution (pH 2.09), and the analytical results were compared with those by classical least squares (CLS), principal components regression (PCR) and partial least squares (PLS). The linear ranges of cefuroxime sodium, ceftriaxone sodium, cefotaxime sodium and cefazolin sodium are 1.0-20.0, 2.0-20.0, 2.0-20.0 and 1.0-18.0 microg x mL(-1), respectively. The proposed procedure was successfully applied in the determination of these drugs in rabbit serum, and the result obtained from spectrophotometry was compared with the one by HPLC with no significant difference found.