ABSTRACT
OBJECTIVE:To establish a method for simultaneous determination of 5 kinds residual ethanol,acetone,ethylacetate,N,N-diisopropylethylamine and toluene in favipiravir.METHODS:Headspace GC was adopted.The determination was performed on DB-624 capillary column,temperature programmed.The inlet temperature was 220 ℃,and detector was flame ionization detector with temperature of 250 ℃.Nitrogen was used as carrier gas at flow rate of 2.0 mL/min,split ratio was 10 ∶ 1,headspace equilibrium temperature was 80 ℃,equilibrium time was 20 min and headspace sample size was 1 mL.RESULTS:The linear range was 10.0-501.4 μg/mL for ethanol(r=0.999 9),10.0-501.4 μg/mL for acetone (r=0.999 9),10.1-502.6 μg/mL for ethylacetate (r=0.999 9),0.2-11.4 μg/mL for N,N-diisopropylethylamine (r=0.999 9)and 1.8-89.4 μg/mL for acetone(r=0.999 7).The limits of quantification were 5.3,3.4,5.2,6.1 and 20.4 μg/mL,and the limits of detection were 1.4,1.1,1.3,1.6,5.9 μg/mL.RSD of precision test was lower than 4.0％,and RSDs of acetone in stability and reproducibility tests were both lower than 4.0％.The recoveries were 96.61％-99.70％ (RSD=1.01％,n=9),95.81％-99.50％ (RSD=1.29％,n=9),96.42％-99.76％ (RSD=1.24％,n=9),96.36％-99.30％ (RSD=1.19％,n=9),97.00％-99.51％ (RSD=0.82％,n=9).CONCLUSIONS:The method is simple,accurate,reproducible and can be used for simultaneous determination of 5 organic solvents in favipiravir.
ABSTRACT
OBJECTIVE:To evaluate the similarity of in vitro dissolution of self-made and original preparation of Ramelteon tablet. METHODS:The paddle method was adopted with rotational speed of 50 r/min,using water,pH1.2 hydrochloric acid solu-tion,pH4.0 acetate buffer solution and pH6.8 phosphate buffer solution as dissolution media,HPLC was used to determine the cu-mulative dissolution of main components of self-made and original preparation of Ramelteon tablet at different time points,dissolu-tion profile was drew,then f2 was used to evaluate its similarity. RESULTS:In the 4 dissolution media,the f2 of self-made and original preparation of Ramelteon tablet was 62.8,80.0,77.7,76.2,respectively,which indicated that the dissolution profiles showed similarity. CONCLUSIONS:The established HPLC is suitable for the dissolution determination of Ramelteon tablet;the dissolution profiles of the self-made and original preparations are similar,it preliminary indicates the prescription and technological rationality of self-made preparation.