为确保进口新冠药物质量，提出了题示方法。样品（约0.600 g）用50%（体积分数，下同）甲醇溶液15 mL超声溶解20 min，并定容至25 mL。取上述溶液10 mL离心，取上清液100 μL用50%甲醇溶液定容至100 mL。所得溶液采用ZORBAX Eclipse XDB-C₁₈柱分离，以不同体积比的甲醇-0.1%（体积分数）三氯乙酸溶液混合液为流动相进行梯度洗脱，多反应监测（MRM）模式进行质谱分析。结果表明，奈玛特韦和利托那韦的质量浓度在2~200 μg·L^-1内与对应的峰面积呈线性关系，测定下限（10S/N）分别为0.85，0.63 μg·L^-1。按照标准加入法进行回收试验，回收率为92.5%~115%，测定值的相对标准偏差（n=6）小于8.0%。方法用于30批实际样品的分析，仅9个样品中检出奈玛特韦和利托那韦有效成分。

In order to ensure the quality of imported novel coronavirus specific drugs, the method mentioned by the title was proposed. The sample (about 0.600 g) was dissolved in 15 mL of 50% (volume fraction, the same below) methanol solution by ultrasound for 20 min, and made its volume up to 25 mL. 10 mL of the above solution was centrifuged, then 100 μL of the supernatant was taken, and made its volume up to 100 mL with 50% methanol solution. The obtained solution was separated on ZORBAX Eclipse XDB-C₁₈ column, using a mixture of methanol and 0.1%(volume fraction) trichloroacetic acid solution at different volume ratios as mobile phase for gradient elution. As shown by the results, linear relationships between values of the corresponding peak area and mass concentration of nirmatrelvir and ritonavir were found in the range of 2-200 μg·L^-1, with lower limits of determination (10S/N) of 0.85 μg·L^-1 and 0.63 μg·L^-1, respectively. Test for recovery was made by the standard addition method, giving the results in the range of 92.5%-115%, with RSDs (n=6) of the determined values less than 8.0%. This method was used for the analysis of 30 batches of actual samples, and the effective constituents of nirmatrelvir and ritonavir were detected in only 9 samples.