秦艽生物碱的薄层色谱扫描测定

用CS-930型双波长薄层扫描仪探讨适合秦艽生物碱定量测定条件。以乙醚—丙酮为展开剂,在硅胶GF₂₅₄板上分离了秦艽甲素和丙素,分别用荧光熄灭和荧光法检出斑点后扫描测定。扫描参数:秦艽甲素λ_s255nm,λ_R280nm;秦艽丙素λ_s300nm,λ_R330nm;反射法锯齿扫描;SX=7;外标一点法;△y=0.2。得到两条通过原点直线。秦艽甲素及丙素的回收率分别为102.75%及100.42%,变异系数分別为2.48%及0.22%。用此法测定了中药秦艽中甲素和丙素的含量;对比了不同产地、同一产地野生和种植、地上和地下部分药材的生物碱含量,为开发秦艽资源提供信息。

STUDIES ON TLC-SCANNING DETERMINATION OF ALKALOIDS IN THE CHINESE DRUG QINJIAO(GENTIANA MACROPHYLLA)

Quantitative determination of the alkaloids in the Chinese drug Qinjiao (G. macrophylla) with a Sbimadzu TLC-scanner is described.Powdered crude drug was extracted with mixed solvent. The extract was directly spotted on a silliea gel GF₂₅₄ plate alongside with the standard substances. Using Et₂O—Me₂CO (5:1) as developing Solvent, the plate was saturated for 30 min and then developed for 16 cm, the alkaloids in the extract were well separated. The spots were detected with fluorescence quenching and fluorometry and scanned by a dual wavelength TLC-seanner Shimadzu model CS-930. The program parameters are: reflectance mode; Zig-Zag scanning; λ_S 255 nm, λ_R 280 nm for gentianine and λ_S 300 nm, λ_R 330 nm for gentianal respectively; SX=7; slit=2×2 mm; △y=0.2; ID Ext=1; two straight lines (gentianine in the range of 4～24μg, gentianal in the range of 0.2～1.2μg) passing through the origin were obtained. The stability of spots was 0.5～6h. The average recoveries of the two alkaloids were 102.75% and 100.42%, the variation coefficients were 2.48% and 0.22%, respectively.This method is simple, rapid, sensitive, accurate and reproducible. It was applied to the determination of gentianine and gentianal in Qinjiao from the same and different habitats. The alkaloid contents were compared in different organs of the same species. Both cultivated and wild Qinjiao were studied. These results showed that the alkaloids contents in Gansu Qinjiao were higher than those in other provinces.