Simultaneous solid phase extraction of chlorpropamide, glipizide and glibenclamide in plasma, using high performance liquid chromatography

Abstract EN

Objective: To develop a rapid, clean and simple simultaneous solid phase extraction procedure for three of the most commonly prescribed sulfonylurea drugs (Chlorpropamide, Glipizide and Glibenclamide) using High Performance Liquid Chromatography.

Method: A C-8 solid phase column (100mg) after the column was conditioned, the sample was mixed with three ml buffer (0.1% orthophosphoric acid) and then applied to the column.

The drugs were eluted from the column with a half ml (four times) acetonitrile after the washing procedure of the column with one ml buffer, then half ml 20% acetonitrile, then applied to a High Performance Liquid Chromatoghraphy, by using the developed method that used a reversed phase C-8 column with a mobile phase consisting of 0.1% orthophosphoric acid pH 2.7: isopropanol: acetonitrile, (45:25:30) operated at ambient temperature, using wave length at 235 nm detector, has been used for the analysis of the extracted drugs (chlorpropamide, glipizide and glibenclamide) Results: A solid phase extraction method has been developed for the simultaneous extraction of three frequently used sulfonylureas: Chlorpropamide, Glipizide and Glibenclamide.

The overall recoveries and relative standard deviations were 98.5%+1.9 for chlorpropamide, 98.9%?+2.4 for glipizide, 97.8%+1.7? for glibenclamide, and 97.5%+2.7 for progesterone internal standard.

The response on High Performance Liquid Chromatoghraphy was linear in the range 1.0- 100?g/ml for Chlorpropamide, Glipizide, and Glibenclamide, with correlation coefficient (r2) > 0.997 for all drugs.

Detection limits were 2ng/ml plasma for Chlorpropamide, 15ng/ml plasma for glipizide and 7ng/ml plasma for glibenclamide, measured at a Signal/Noise (S/N) of three.

No interference from administered drugs (Barbiturates, B-blockers, Tranquilizer, Antihypertensive, Histamine antagonist, Antidepressant, Antiemetic, and Anticonvulsant) or endogenous constituents were observed.

Conclusion: The developed method, with its high recoveries for the chlorpropamide, glipizide and glibenclamide, can be applied for clinical, forensic toxicology as well as in the bioavailability or bioequivalence studies or in the study of these drugs in pharmaceutical products.