Original Article DEVELOPMENT AND VALIDATION STABILITY INDICATING HPTLC METHOD FOR DETERMINATION OF VILDAGLIPTIN AND METFORMIN HYDROCHLORIDE IN THE PHARMACEUTICAL DOSAGE FORMS ATUL R. BENDALE, R. P. SINGH, G. VIDYASAGAR 1,2 Dept. of Pharmaceutical Sciences, Suresh Gyan Vihar University, Jaipur, Rajasthan, 3 Pharmacy Department, Kutch University, Bhuj, Gujarat Email: atulbendale123@gmail.com Received: 06 Jun 2017, Revised and Accepted: 28 Nov 2017 ABSTRACT Objective: A simple, precise, and accurate stability indicating high-performance thin layer chromatography method was developed and validated of vildagliptin (VIL) and metformin (MET) in pharmaceutical dosage forms. Methods: In the present study, system suitability test, stress study, alkali hydrolysis, acid hydrolysis, neutral hydrolysis, oxidative stress degradation, dry heat degradation, wet heat degradation, photodegradation study has been used. In this method, optimization by changing various parameters, such as organic solvent and the composition of the mobile phase, acid or base modifier used in the mobile phase; by varying one parameter and keeping all other conditions constant. 10 µl of the stock solution for MET (500 ng/band) and 2 µl of the stock solution for VIL (100 ng/band) were applied to TLC plates. The final solutions were applied on the HPTLC plates and these were developed as per the optimized densitometry conditions. Results: From the spectra, it was observed that MET and VIL exhibited good absorbance at about 217 nm. Both the drugs showed degradation with additional peaks at Rf values of 0.16 for MET and with Rf values 0.81 for VIL respectively. The method was validated for linearity, precision, accuracy, limit of detection, limit of quantification, ruggedness, specificity, and robustness. Good separation was achieved by using the mobile phase Hexane: Methanol: Acetonitrile: Glacial Acetic Acid (2:3.5:2.5:0.2 v/v/v/v) with retardation factor (Rf) values of 0.22±0.01 for MET and 0.73±0.02 for VIL. Conclusion: A validated HPTLC method was developed for the determination of metformin hydrochloride and vildagliptin. The method is simple, quick, and can be applied routinely for the analysis of these drugs from marketed dosage forms. Keywords: Metformin hydrochloride, Vildagliptin, Method validation, HPTLC © 2018 The Authors. Published by Innovare Academic Sciences Pvt Ltd. This is an open access article under the CC BY license (http://creativecommons.org/licenses/by/4.0/) DOI: http://dx.doi.org/10.22159/ijap.2018v10i1.20555 INTRODUCTION Metformin (MET) is known for its anti-diabetic properties, which is chemically, 1,1-dimethyl biguanide hydrochloride [1]. The important properties include; high efficacy, safety profile, beneficial cardiovascular and metabolic effects and therapeutic benefit in association with other antidiabetic drugs. Therefore metformin is included in first-line therapy to treat patients with type II diabetes mellitus [2]. In the present study, complimentary actions have drawn in focus to the usage of metal ong with a newer class of anti- diabetic drugs, VIL the dipeptidyl peptidase (DPP)-4 inhibitors [1]. The literature survey reveals that several analytical methods are reported for quantitative estimation of metformin alone in body fluids and in pharmaceutical formulations. Those methods include spectrophotometry, electrochemical methods, HPLC, liquid chromatography-electrospray ionization tandem mass spectrometry and electrophoresis [3]. Reverse phase high performance liquid chromatographic method (RP-HPLC) for simultaneous estimation of metformin is also reported [4]. Studies have shown that age, gender, and body mass index (BMI) have no clinically relevant effects on the pharmacokinetics or pharmacodynamics of vildagliptin [5, 6] till time there is no noted HPTLC method for the estimation for vildagliptin and metformin hydrochloride combination in the pharmaceutical dosage forms. A synchronized improvement in β-cell function was also observed in subjects who had higher baseline HbA1C levels showed a greater response to metformin and vildagliptin treated patients [7, 8]. The present study was aimed to develop and validation stability indicating HPTLC method for determination of vildagliptin and metformin hydrochloride in the pharmaceutical dosage forms. MATERIALS AND METHODS Pure vildagliptin and metformin hydrochloride were procured from Matrix Pharma, Nashik, India as a gift sample. Acetonitrile, methanol, and water were all of HPLC grade procured from Merck Ltd., Mumbai, India. Potassium dihydrogen phosphate, hydrochloric acid, sodium hydroxide, anhydrous sodium acetate, glacial acetic acid, orthophosphoric acid were purchased from Priya scientifics, Vapi, India, were of analytical reagent grade. Preparation of solutions Stock standard solution VIL and MET was prepared by dissolving 7.5 mg VIL and 300 MET in methanol in a 50 ml volumetric flask. Working standard solution of VIL and MET was prepared at a concentration of 15 ng µl-1 and 600 ng µl-1 respectively, by diluting the stock standard solution in methanol. The stock solution was stored at 2-8 ° C protected from light. Instrumentation The samples were spotted in the form of bands 6 mm width with a Camag 100 microlitre sample syringe (Hamilton, Bonaduz, Switzerland) on silica gel precoated aluminum plate 60 F254, [(20 × 10 cm) with 250 µm thickness; E. Merck, Darmstadt, Germany, supplied by Anchrom Technologists, Mumbai] using a Camag Linomat IV applicator (Switzerland). The plates were prewashed with methanol and activated at 110 ° C for 5 min prior to chromatography. A constant application rate of 0.1 µls-1 was used and the space between two bands was 6 mm. The slit dimension was kept at 5 mm × 0.45 mm and the scanning speed was 10 mm s-1. Linear ascending development was carried out in 20 cm × 10 cm twin trough glass chamber (Camag, Muttenz, Switzerland) saturated with the mobile phase. The optimized chamber saturation time for mobile phase was 30 min at room temperature (25±2 ° C). The length of chromatogram run was 8 cm. Densitometric scanning was performed using a Camag TLC scanner III in the reflectance-absorbance mode and operated by CATS software (V 3.15, Camag). The sources of radiation used were deuterium and tungsten lamp with a spectral range from International Journal of Applied Pharmaceutics ISSN- 0975-7058 Vol 10, Issue 1, 2018