反相高效液相色谱法测定植物组织及根分泌物中草酸

采用反相C1 8柱 ,2 2 0nm紫外检测 ,0 .5 %KH2 PO4 0 .5mmol L四丁基硫酸氢铵 (tetrabutylammoniumhydrogensulfate ,TBA) (pH 2 .0 )的水溶液体系 ,可使草酸及其它测试的 6种有机酸及硝酸有效分离。进一步研究了该方法测定植物组织及根分泌物中草酸的效果 ,结果表明其精确灵敏、回收率高、重复性好 ,并且成本低、操作简便 ,可应用于各种生物材料、食品、饮料等产品中的草酸含量检测。

Determination of Oxalic Acid in Plant Tissue and Root Exudate by Reversed Phase High Performance Liquid Chromatography

An improved method was described for the determination of oxalic acid in plant samples by reversed-phase high performance liquid chromatography. A reversed-phase C 18 column, an ultraviolet detector at 220 nm, and a mobile phase containing 0.5% KH 2PO 4 and 0.5 mmol/L tetrabutylammonium hydrogen sulfate (pH 2.0) were applied to the system, which allowed a good separation of oxalic acid from nitrate and other organic acids. The method was further tested for the analysis of the samples of soybean leaves and the root exudate, showing it is precise, sensitive and highly reproducible. The detection limit is 1.43 ng, relative standard deviation is 2.8% ( n=21). Recovery is around 100%. In addition, the collecting method of root exudate was improved to avoid loss of oxalic acid during the preparation, by which it is much easier to monitor the oxalic acid exuded from the non-oxalic acid accumulating plants.