Chemometric resolution of fully overlapped capillary electrophoresis bands: quantitation of carbamazepine in human serum in the presence of several interferences

H. GOICOECHEA; CULZONI MARÍA JULIA; VERA CANDIOTI, LUCIANA; AC OLIVIERI,

Reno, USA

Congreso; Annual Meeting Federation of Analytical Chemistry and Spectroscopy Society (FACSS 2008); 2008

facss

Drug monitoring in serum samples was performed using second-order data generated by capillary electrophoresis-diode array detection, processed with a suitable chemometric strategy. Carbamazepine could be accurately quantitated in the presence of its main metabolite (carbamazepine epoxide), other therapeutic drugs (lamotrigine, phenobarbital, phenytoin, phenylephrine, ibuprofen, acetaminophen, theophylline, caffeine, salicylic acid), and additional serum endogenous components. The analytical strategy consisted of the following steps: a) serum sample clean-up to remove matrix interferences, b) data pre-processing, in order to reduce the background and to correct for electrophoretic time shifts, and c) resolution of fully overlapped capillary electrophoretic peaks (corresponding to carbamazepine, its metabolite, lamotrigine and unexpected serum components) by the well-known algorithm multivariate curve resolution - alternating least squares, which extracts quantitative information that can be uniquely ascribed to the analyte of interest. Mean recoveries were 102.6 % (s = 7.7) for binary samples, and 94.8 % (s = 13.5) for spiked serum samples, while CV(%) = 4.0 was computed for five replicates, indicative of the acceptable accuracy and precision of the proposed method.