液相色谱串联质谱法测定人血浆中巴洛沙韦酸浓度OA

Objective To establish a liquid chromatography-tandem mass spectrometry(LC-MS/MS)method for determining the concentration of baloxavir acid in human plasma.Methods After protein precipitation with methanol,plasma samples were analyzed with dolutegravir as the internal standard.The chromatographic column was Phenomenex Luna®-C8 column(50 mm×2.1 mm,3 μm),the mobile phase was methanol-0.1%aqueous formic acid solution(gradient elution),the flow rate was 0.35 mL/min,the column temperature was 25℃,and the injection volume was 10 μL.Electrospray ionization was used with a positive ion mode for multiple reaction monitoring.The ion pairs for analysis with mass-to-charge ratios(m/z)of 484.20 → 247.20(baloxavir acid)and 420.00 → 277.10(dolutegravir)were adopted.Results The linear range of baloxavir acid was 0.50-80.00 ng/mL(r=0.999 3,n=8).The lower limit of quantification was 0.50 ng/mL.The RSDs of the intra-day and inter-day precision tests were in the ranges of 3.27%-5.87%(n=3)and 0.62%-9.12%(n=3),respectively.The RSD of the stability test was lower than 5％.The extraction recovery rate was in the range of 89.90％-96.94％,and the matrix effect was in the range of 100.76％-115.00％.Conclusion This method is simple,highly specific,accurate,and stable,which can be used to determine the concentration of baloxavir acid in human plasma.