ABSTRACT
Objective:To study on the pharmacokinetics and tissue distribution of baicalin magnesium salt in rats after tail vein injection,and compare pharmacokinetic differences between baicalin magnesium salt and baicalin. Method:After tail vein injection of baicalin magnesium salt and baicalin,orbital blood was collected at different time points.The drug concentration was measured by HPLC,the drug concentration-time curve was plotted,the pharmacokinetic parameters were calculated with DAS 3.0 software,SPSS 19.0 software was used for statistical analysis.At the same time,the drug distribution in heart,liver,spleen,lung and kidney was measured at different time points after tail vein injection of baicalin magnesium salt. Result:When the dose of baicalin magnesium salt was 25-100 mg·kg-1,area under the curve(AUC0-t and AUC0-∞) showed a good linear relationship with the dose(r>0.95),but most of the other pharmacokinetic parameters had no significant difference between different dose groups.The mean residence time(MRT0-t) of medium dose group of baicalin magnesium salt was significantly higher than that of equal molar dose group of baicalin.After intravenous injection of baicalin magnesium salt,the drug concentration was the highest in each tissue at 0.25 h,and the concentration of target component decreased rapidly at 0.75 h.The distribution of target component in kidney was the most,followed by lung. Conclusion:After injection,the baicalin magnesium salt can be rapidly distributed and quickly eliminated in vivo,which is mainly excreted from the kidney.
ABSTRACT
OBJECTIVE:To study the stability of baicalin magnesium salt. METHODS:The stability of baicalin magnesium salt at high temperature(60 ℃),high humidity(90%),strong illumination(4000 lx),different temperatures(20,37,50,60 ℃) and pHs(6.80,5.70,4.60,4.30,3.90,3.60,3.20) was investigated,and HPLC was used to detect the drug contents. RESULTS:High humidity test indicated that the quality of baicalin magnesium salt was increased by (6.17 ± 0.12)% in the 5th day and in-creased by(6.92±0.05)% in the 10th day. Drug contents in the 10th day were respectively(94.78±0.12)%,(94.79±0.20)%, (94.66±0.15)% in the high temperature,high humidity,strong illumination tests(n=3). In phosphate buffer solution(pH 6.80), baicalin magnesium salt was stable only when the temperature was below 20 ℃;and it was yet stable in pure water(pH 6.76)at 37 ℃. pH stability test showed that the most stable pH was 4.30. CONCLUSIONS:Baicalin magnesium salt has hygroscopicity to some extent. Strong illumination affects the stability more seriously than high temperature and high humidity. The stability of ba-icalin magnesium salt in pure water is superior to in phosphate buffer solution,and the salt is stable in weak acid solution.