Capillary electrophoresis for analysis of sulfonylureas in human serum

Abstract
Diagnosis of "factitious hypoglycaemia" is essentially based on the disclosure of hypoglycaemic agents in blood or urine. Aim of this study was to check the performance of capillary electrophoresis as a quantitative method for determination of chlorpropamide, tolbutamide, glipizide, gliclazide, glibenclamide in serum. Samples were added with the internal standard, purified by solid phase extraction and analysed by micellar electrokinetic capillary chromatography. Pharmacokinetics of gliclazide (80 mg tablet) in a diabetic patient was assayed by capillary electrophoresis and gave results superimposable to the one found by HPLC. Two hypoglycaemic patients positive by HPLC analysis to unreported gliclazide and tolbutamide overdosage, were screened also by capillary electrophoresis that confirmed the HPLC diagnosis of surreptitious abuse of sulfonylurea drugs. Linearity (r² ³ 0.998) and recovery (³ 80%) were good for all the sulfonylurea drugs tested demonstrating its usefulness also for a quantitative application.

Key words
Capillary electrophoresis, sulfonylureas, plasma

Bibliografía del artículo

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