Simultaneous Estimation and Validation of Four Antiepileptic Drugs from Bulk and Formulations Using Reverse Phase HPLC

Abstract Epilepsy is a disorder of the central nervous system, in which the nerve cell activity in the brain is disturbed causing seizures. The objective was to develop an RP-HPLC method for consistent simultaneous quantitation of four antiepileptic drugs Levetiracetam (LVT), Lamotrigine (LTG), Phenobarbital (PBT) and Phenytoin (PTY). An isocratic method was developed on C18 column in JASCO HPLC using 5 mM potassium phosphate buffer (pH 6) and acetonitrile as the mobile phase at a flow rate of 1ml/min and detected at 230 nm using UV detector. The mean retention time for LVT, LTG, PBT and PTY were found as 2.55, 3.55, 4.65 and 5.99 minutes respectively. The method was validated as per ICH guidelines and was found to be acceptable. The %RSD value was <2.0 % thus stating the developed method was precise for the drugs in the given range. The accuracy values were within 85-115% of the recovery range. The specificity of the method was evaluated by an assay of marketed formulation, and it showed a percent content between 90-110% w/w for all the four drugs. The proposed analytical method was simple, accurate and robust and was precisely able to resolve the four major antiepileptic drugs. Hence, the current method can be applied successfully for routine examination of these drugs

Quantitative Estimation of Piperine and Diosgenin in Ayurvedic Formulation.

Goksuradi guggulu is a polyherbal formulation official in “Ayurvedic formulary of India” and used for dysuria, urinary obstruction, increased frequency and turbidity of urine, calculus, excessive vaginal discharge, gout. A simple, specific and precise high performance thinlayer chromatography (HPTLC) method has been developed for quantification of piperine and diosgenin in Goksuradi guggulu. We report the extraction and estimation of these compounds in a laboratory prepared sample of Goksuradi guggulu and two of its marketed formulations. The compounds were chromatographed on precoated silica gel G 60 254 plates in the mobile phase comprising of toluene: hexane: ethyl acetate (6.8:0.2:3). Under the optimized chromatographic conditions, the calibration plot was found to be linear in the range of 0.2-1μg spot-1 for piperine and 1.0 -3.0 μg spot-1 for diosgenin. The correlation coefficient (R2) was 0.9979 and 0.9915 for piperine and diosgenin respectively. Mean recovery (% w/w) for piperine in all the formulations was in the range of 97.61 - 98.90 and for diosgenin, it was 93.76 - 94.33.