Development and validation of HPLC-UV-MS method for the control of four anti-diabetic drugs in suspected counterfeit products

An HPLC-UV method has been developed for the determination of valibose, miglitol, voglibose and acarbose, the four anti-diabetic drugs.  The separation was accomplished successfully by using reversed phase chromatography (Prevail carbohydrate column, 250 mm ´ 4.6 mm, 5 μm) with a gradient acetonitrile- phosphate buffer solution (pH 8.0) at a wavelength of 210 nm.  Furthermore, the method of a high-performance liquid chromatography coupled with ESI-MS in positive ionization mode has been established.  These two methods were successfully applied to the assay and qualitative detection of four α-glucosidase inhibitors in the potential counterfeit anti-diabetic drugs.