RESUMEN
Objective To establish a method for determination of the twelve residual organic solvents,including methanol,ethanol,acetone,isopropanol,tert-Butyl methyl ether,dichloromethane,aceticether,tetrahydrofuran,triethylamine,trimethylorthofor-Mate,morpholine,N,N-Dimethylformamide in Apixaban bulks drug.Methods Gas head-space chromatography was applied to this study.The column was DB-624 silica capillary column (30.0 m × 0.53 mm × 3.00 μm) and the carrier gas was high purity nitrogen;The vial temperature was 100 ℃,and the vial time was 20 min.The Column temperature was kept at 40 ℃ for 6 min,then the temperature was raised to 220 ℃ at the rate of 20 ℃/min and subsequently sustained for 10 min.FID detector temperature and injection temperature were both 250 ℃.The N2 flow rate was 2.8 mL/min.Split ratio was 5∶1.Results Twelve kinds of solvents were completely separated and determined with a good linearity (r =0.9994-0.9999).The RSD values of precision experiments and the average recovery was in line with the requirements.Conclusion Theanalytical method is simple,accurate and sensitive,which could be used for determination of residual organic solvents in Apixaban bulks drug.
RESUMEN
Objective To develop a reversed phase high performance liquid chromatography ( RP￣HPLC) method determining the related substances and levidipine. Methods The Welchrom C18 column (250 mm×4.6 mm,5 μm) was used with Octadecylsilane bonded silica as a filler.The mobile phase consisted of methanol￣ethanol￣water (40:20:40),at the flow rate of 1 mL.min-1 in an isocratic elution,the temperature was at 45 ℃ , and the detective wavelength was 240 nm. Results Levidipine could be separated from all impurities and intermediates within the concentration range from151 to 604 ng.mL-1 , which had a satisfied linear relationship (r= 0.999 9) with a regression equation of Y= 0.049 9X+0.597 9.The LOQ of detection was 31.9 ng.mL-1 . Conclusion The developed method is specific,sensitive,easy and fast to operate,which is suitable for detecting levidipine and its related impurities.