高效液相色谱法测定大黄酸的含量

HPLC DETERMINATION OF RHEINIC ACID

建立了测定大黄酸含量的高效液相色谱方法。分析柱为Waterssy Tnmetry C18色谱柱（150min×4·6mm，5μm），流动相为甲醇-水-冰乙酸（70：30：2，体积比），流速0．8mL·min^-1。检测波长为254nm，回收率为99．4%-100．2％，用于原料（掌叶大黄）和产品（大黄酸）的质量控制，同一天对大黄酸标准溶液连续测定和每隔1h进样一次测定（n=6）的相对标准偏差为0．6%～0.8％。经测定原料（掌叶大黄）中大黄酸的质量分数为0．58％，产品中大黄酸的质量分数为73．1％～90．4％。

HPLC was applied to the determination of rhein （or called rheinic acid）. The Waters symmetry C18 （150 mm×4. 6 mm, 5 μm） was used as the stationary phase, and a mixed solution of methanol, water and acetic acid in the ratio of 70 to 30 to 2 （by volume） was used as the mobile phase. UV-detection at the wavelength of 254 nm was used. The flow-rate of mobile phase was 0. 8 mL ·min^-1, Precision tests of within-day and between- days repeatability, and of reproducibility in the same laboratory were performed, and RSD＇s （n=6） of repeatability obtained were in the range of 0. 6%-0. 8% and RSD （n=6） of reproducibility was 0. 7%. Recovery were tested at 3 different concentration levels giving values in the range of 99. 4%-100. 2%. In the determination of rheinic acid in its raw material （palmate leaf chinese rhubarb） and products, 0. 58% of rheinic acid was found in the raw material, and contents of rheinic acid in the products were in the range of 73. 1%-90. 4%.