采用双波长薄层扫描法测定了祛白片中补骨脂素和异补骨脂素的含量。补骨脂素回收率平均值为９８．９６％，变异系数为２．８６％（ｎ＝５）；异补骨脂素回收率平均值为９８．３８％，变异系数为２．７９％（ｎ＝５）。本法简便、快速、结果可靠 The content of psoralen and isopsoralen in Qu Bai tablets was determined by dual-wavelength TLC scanning. The average recovery of psoralen was 98.96% and the coefficient of variation was 2.86% (n = 5). The average recovery of isopsoralen was 98.38% and the coefficient of variation was 2.79% n = 5). This method is simple, fast and reliable