Development and Validation of a Headspace Gas Chromatographic (HS-GC) Method for Determination of Residual Solvents in Nitazoxanide API

Abstract

Controlling residual solvents in the drug substances or active pharmaceutical ingredients (API) is mandatory to the specified limits as per the International Conference on Harmonisation (ICH) Q3C guidelines. Residual solvents in pharmaceuticals are mostly determined by Gas Chromatography with Headspace. A simple and sensitive headspace gas chromatographic (HS-GC) method has been developed for the determination of Acetone, Dichloromethane and Cyclohexane in Nitazoxanide API. The separation of analytes was achieved with DB – 624 (30 m length, 0.53 mm inner diameter and 3.0 µm in film thickness) capillary column. Dimethyl formamide was used as adiluent. Nitrogen was used as carrier gas with 3.0 mL/minutes and Flame ionisation detector (FID) for detecting analytes. The oven temperature was set at 60^◦C for 5 minutes at initial and programmed at a rate of 20^◦C per minute to a final temperature of 240^◦C for 2 minutes. Run time was 16 minutes, and total GC cycle time was 25 minutes. The spilt ratio used as 1:20 to get optimum peak response. The developed method was validated as per the ICH guidelines for specificity, accuracy, precision, linearity, range, the limit of detection, the limit of quantification and robustness. The results of validation were indicated no interference, good recoveries, precise, linear, rugged and robust method, suitable for the determination of residual solvents in Nitazoxanide API for research and routine quality control laboratory.