Research Article DUAL RUN-DUAL WAVELENGTH HPTLC METHOD DEVELOPMENT AND VALIDATION FOR DETERMINATION OF FIVE ANTIDIABETIC DRUGS IN BULK AND THEIR PHARMACEUTICAL DOSAGE FORMS ARPIT PATWARI a* , URVISH DESAI a , BHANUBHAI SUHAGIA b a Department of Quality Assurance, L.M. College of Pharmacy, Ahmedabad, Gujarat, India. b Faculty of Pharmacy, Dharamsinh Desai University, Nadiad, Gujarat, India. Email: patwari_arpit@yahoo.com Received: 18 May 2013, Revised and Accepted: 09 Jun 2013 ABSTRACT Objective: A sensitive, selective, precise and validated high-performance thin layer chromatographic method for analysis of five Antidiabetic drugs in bulk and their available combined dosage forms has been developed. Methodology: The method employed TLC aluminum plates precoated with silica gel 60 F254 as the stationary phase. A dual run technique was adopted for better resolution amongst all five drugs with solvent system initially chloroform: methanol: Ammonia (9:1:0.2 v/v/v) upto half the height of the plate. The plates were dried and developed again in system chloroform: methanol: Ammonia (9:1.5:0.2 v/v/v) of higher polarity till 80 mm height. This was found to give compact spots for all five drugs. (Rf value of Metformin Hydrochloride, Repaglinide, Glimepiride, Pioglitazone and Sitagliptin Phosphate = 0.10 ±/0.02, 0.23 ±/0.02, 0.45 ±/0.02, 0.54 ±/0.02 and 0.66 ±/0.02 respectively). Densitometric analysis was carried out in the absorbance mode at 238 nm for Metformin Hydrochloride (MFH), Repaglinide (REP) and Glimepiride (GLM) while at 268nm for Pioglitazone (PIO) and Sitagliptin Phosphate (SGP). Results: The linear regression data for the calibration plots showed good linear relationship with r 2 close to 0.9999 in the concentration range of 200-800 ng/spot for drugs other than SGP which showed linearity between 2000-8000ng/spot. The method was validated for precision, accuracy, ruggedness and recovery as per ICH guidelines and was applied for quantification in various formulations. Conclusion: The developed method could be used for quantification of any of the selected five drugs in bulk or in their available combined pharmaceutical dosage forms. Keywords: HPTLC Method, Antidiabetic Drugs, Dual Run Technique, Simultaneous Determination INTRODUCTION With advancement and modernization in field of drug development, newer and newer drugs have been invented every year. In past two decades several new categories of oral antidiabetic drugs have been invented and formulated in various combinations. A market survey carried out clearly indicated the use of oral antidiabetics i.e. Metformin Hydrochloride, Repaglinide, Glimepiride, Pioglitazone and newer DPP4 inhibitor drug Sitagliptin Phosphate, either alone or in combination with one another, the most by physicians and specialists. Metformin Hydrochloride (MFH) and Glimepiride (GLM) are sulphonylureas; Repaglinide (REP) a metaglinide; Pioglitazone (PIO) a thiazolidinedione and Sitagliptin Phosphate (SGP) a DPP4 inhibitor[1] (Figure 1) regulates the control of insulin in body via several mechanisms and maintains body’s glucose levels. Today Indian markets are flooded with more than 800 generic brands of these drugs and same is the scenario globally [2]. Several methods like UV, HPLC, LC-MS, LC-MS MS and capillary electrophoresis [3-21] have been developed for quantification of these drugs alone or in combination. Due to its better resolution, cost effectiveness and higher sensitivity, High pressure thin layer chromatography is a widely adopted method of analysis. Thus it was thought of interest to develop a universal industrially applicable method for quantification of these drugs using HPTLC method. Fig. 1: Structures of Antidiabetic drugs International Journal of Pharmacy and Pharmaceutical Sciences ISSN- 0975-1491 Vol 5, Suppl 3, 2013 A A c c a a d d e e m mi i c c S S c c i i e e n n c c e e s s