目的 建立一种判定多糖中有无糖醛酸残基的简便可靠的方法。方法 采用 TL C分析了含糖醛酸的多糖还原前后的样品以及标准葡聚糖分别酸水解 2和 4h的产物 ,以探讨传统 TL C方法是否可靠。并将含糖醛酸的多糖及中性多糖完全酸水解产物进行 TL C检测 ,糖醛酸标准品为对照 ,以苯胺 -邻苯二甲酸显色检测糖醛酸 ,此外 ,考察了其灵敏度 ,并与已有的方法比较。结果 传统方法中的荧光斑点系由 CF₃COOCH₃以及反应过程中其他副产物产生的 ,并非糖醛酸产生。新法可检测出 0 .5 μg的糖醛酸 ,无假阳性结果。结论 传统方法缺乏必要的理论依据 ,容易误导结构研究。以糖醛酸标准品为对照 ,对多糖样品完全酸水解产物进行薄层层析后 ,采用苯胺 -邻苯二甲酸显色能可靠地判定糖醛酸的有无.

Object To develop a simple and reliable method to detect the presence of uronic acids in poly saccha rides. Methods Uronic acid co ntaining polysaccharides and standard glucons were subjected to acid hydrosis for 2 h and 4 h respectively. Samples of the product s, before and af ter hydrolysi s were analy zed by TLC using standard uronic acid as the control and amino benzen-alizaric acid as the chromo genic ag ent , to compa re the sensi tivi ties in the detection of uronic acid used in the present conventio nal analysis. Results The f luorescent spo t s used as criterio n in t raditional TLC method were not shown by uronic acids, but by CF₃COO CH₃ and other by-products in reaction. 0. 5μg of uronic acid could be detected with our method, without false positive reaction. Conclusion The traditional T LC method seemed to lack theo rectical backg round a nd may mi slead structural study. The present method in mo re reliable to detect uro nic acids in poly saccha rides by analy zing the complete hydro lytic products of polysaccharides using T LC with standard uronic acids as control and aminobenzene-alizaric acid as ch romog enic agent.