Screening and Quantitative Analysis for Sulfonylurea-Type Oral Antidiabetic Agents in Adulterated Health Food Using Thin-Layer Chromatography and High-Performance Liquid Chromatography

Screening and quantitative analysis for six sulfonylurea-type oral antidiabetic agents (SU-OADs), tolbutamide (TOL), acetohexamide (ACE), chlorpropamide (CHL), gliclazide (GLC), glibenclamide (GLB), and glimepiride (GLM), in adulterated health food has been developed. The SU-OADs were extracted with acetone and then the extract was subjected to thin-layer chromatography (TLC) and high-performance liquid chromatography (HPLC). In the TLC analysis, good separation was achieved with a mixture of n-butyl acetate containing 0.4% formic acid as a solvent. Ultraviolet irradiation at 254 nm was used to detect the SU-OADs. Specificity was obtained with Dragendorff's test solution, 10% phosphomolybdic acid methanol solution, and 30% sulfuric acid methanol solution. On the other hand, with a gradient reverse-phase HPLC system equipped with a photodiode array detector, we were able to detect the SU-OADs within 15 min using an ODS column and acetonitrile-ammonium acetate buffer as a mobile phase. Quantitative analysis based on HPLC was also performed with the absolute calibration curve method. Recoveries were 90.7-105.2% for the drugs tested. The intra- and interassay relative standard deviations were 0.2-8.1 and 0.6-7.2%, respectively. When the methods were applied to prescription glibenclamide tablets, health food, and spiked samples, good selectivity, separation, recovery, and precision were obtained.