Determination of Residual Organic Solvents in Finasteride by Headspace Capillary Gas Chromatography

The study developed a method using headspace capillary gas chromatography to determine residual organic solvents, specifically chloroform and dichloromethane, in finasteride. The method effectively separated the solvent peaks and demonstrated excellent linearity with correlation coefficients of 0.9997 and 0.9998. The detection limits were 3.2 μg/L for chloroform and 0.094 μg/L for dichloromethane, with relative standard deviations (RSDs) of 1.33% and 0.89%, respectively. Factors such as equilibrium times, equilibrium temperature, and salting-out were also examined to optimize the method.