Author(s): Ravindra B. Nehete, Pushpendra Sharma
Testing of residual solvent is a primary requirement for any drug substance. These studies provide information about the residual solvents content in Iguratimod with simple, accurate, precise by heads pace gas chromatography. Method by head space gas chromatography with flame ionization detector has been developed and validated to detect and quantitate the specified solvents. Baseline separation in-between the peaks were been achieved by suing capillary column with a flame ionization detector. Percentage recovery obtained in the range of 80-120% and the method is linear for all the specified solvents as per synthesis route of synthesis of Iguratimod. Range for these method is listed for each solvent - Ethanol (50ppm - 7500ppm), Acetone (50ppm - 7500ppm), Isopropyl alcohol (50ppm - 7500ppm), Acetonitrile (20ppm - 615ppm), Dichloromethane (30ppm - 900ppm), Ethyl acetate (50ppm - 7500ppm), Methanol (30ppm - 4500ppm), Pyridine (20ppm - 300ppm), Dimethyl formamide (88ppm - 1320ppm), Benzene (0.2ppm - 3ppm), Nitrobenzene (3ppm - 45ppm). All five methods are having the coefficient of variation (r) not less than 0.99. This proposed methodology was found precise, linear and accurate for the specified range for respective solvents.