Sofosbuvir is one of the new direct-acting antiviral drugs against hepatitis C virus(HCV) infection. This drug has recently been launched into the market, and generic versions of the medication are expected to be prod...Sofosbuvir is one of the new direct-acting antiviral drugs against hepatitis C virus(HCV) infection. This drug has recently been launched into the market, and generic versions of the medication are expected to be produced by local drug producers in some countries. Therefore, new methods are required to control sofosbuvir in pharmaceuticals. In the present study, a new method based on reversed phase(RP)-ultra-high performance liquid chromatography(UHPLC) coupled to diode array detection(DAD) and mass spectrometry(MS) was developed to facilitate the qualitative and quantitative analysis of sofosbuvir in film coated tablets. A wavelength of 260 nm was selected to perform a cost-effective quantification and the method showed adequate linearity,with an R^2 value of 0.9998, and acceptable values of accuracy(75%–102%) and precision(residual standard deviation < 5%). The detection and quantification limits were 0.07 μg/mL and 0.36 μg/mL, respectively.Furthermore, the use of high-resolution MS enabled us to ensure the specificity, check impurities and better sensitivity. Therefore, this methodology promises to be suitable not only for the routine analysis of sofosbuvir in pharmaceutical dosage forms, but also for potential degradants.展开更多
Drug stability is closely related to drug safety and needs to be considered in the process of drug production,package and storage.To investigate the stability of epalrestat,a carboxylic acid derivative,a reversed-phas...Drug stability is closely related to drug safety and needs to be considered in the process of drug production,package and storage.To investigate the stability of epalrestat,a carboxylic acid derivative,a reversed-phase high-performance liquid chromatography(RP-HPLC)method was developed in this study and applied to analyzing the degradation kinetics of epalrestat in aqueous solutions in various conditions,such as different pH,temperatures,ionic strengths,oxidation and irradiation.The calibration curve was A=1.6×10^5C–1.3×10^3(r=0.999)with the liner range of 0.5–24μg/mL,the intra-day and inter-day precision was less than 2.0%,as was the repeatibility.The average accuracy for different concentrations was more than 98.5%,indicating that perfect recoveries were achieved.Degradation kinetic parameters such as degradation rate constants(k),activation energy(Ea)and shelf life(t0.9)under different conditions were calculated and discussed.The results indicated that the degradation behavior of epalrestat was pH-dependent and the stability of epalrestat decreased with the rised irradiation and ionic strength;however,it was more stable in neutral and alkaline conditions as well as lower temperatures.The results showed that the degradation kinetics of epalrestat followed first-order reaction kinetics.Furthermore,the degradation products of epalrestat under stress conditions were identified by UHPLC-PDA-MS/MS,with seven degradation products being detected and four of them being tentatively identified.展开更多
基金the postdoctoral grant associated to the Excellence Project P11-CTS-7625, which was also financed by the previous entity
文摘Sofosbuvir is one of the new direct-acting antiviral drugs against hepatitis C virus(HCV) infection. This drug has recently been launched into the market, and generic versions of the medication are expected to be produced by local drug producers in some countries. Therefore, new methods are required to control sofosbuvir in pharmaceuticals. In the present study, a new method based on reversed phase(RP)-ultra-high performance liquid chromatography(UHPLC) coupled to diode array detection(DAD) and mass spectrometry(MS) was developed to facilitate the qualitative and quantitative analysis of sofosbuvir in film coated tablets. A wavelength of 260 nm was selected to perform a cost-effective quantification and the method showed adequate linearity,with an R^2 value of 0.9998, and acceptable values of accuracy(75%–102%) and precision(residual standard deviation < 5%). The detection and quantification limits were 0.07 μg/mL and 0.36 μg/mL, respectively.Furthermore, the use of high-resolution MS enabled us to ensure the specificity, check impurities and better sensitivity. Therefore, this methodology promises to be suitable not only for the routine analysis of sofosbuvir in pharmaceutical dosage forms, but also for potential degradants.
文摘Drug stability is closely related to drug safety and needs to be considered in the process of drug production,package and storage.To investigate the stability of epalrestat,a carboxylic acid derivative,a reversed-phase high-performance liquid chromatography(RP-HPLC)method was developed in this study and applied to analyzing the degradation kinetics of epalrestat in aqueous solutions in various conditions,such as different pH,temperatures,ionic strengths,oxidation and irradiation.The calibration curve was A=1.6×10^5C–1.3×10^3(r=0.999)with the liner range of 0.5–24μg/mL,the intra-day and inter-day precision was less than 2.0%,as was the repeatibility.The average accuracy for different concentrations was more than 98.5%,indicating that perfect recoveries were achieved.Degradation kinetic parameters such as degradation rate constants(k),activation energy(Ea)and shelf life(t0.9)under different conditions were calculated and discussed.The results indicated that the degradation behavior of epalrestat was pH-dependent and the stability of epalrestat decreased with the rised irradiation and ionic strength;however,it was more stable in neutral and alkaline conditions as well as lower temperatures.The results showed that the degradation kinetics of epalrestat followed first-order reaction kinetics.Furthermore,the degradation products of epalrestat under stress conditions were identified by UHPLC-PDA-MS/MS,with seven degradation products being detected and four of them being tentatively identified.