预衍生化-毛细管柱气相色谱法测定单糖

Capillary Column-Gas Chromatographic Determination of Monosaccharides with Pre-derivatization

对气相色谱法测定单糖时所用的毛细管色谱柱及单糖的预衍生化方法作了比较研究。在3种常用的衍生化方法中,选用了在盐酸羟胺及乙酸酐存在下将单糖转化成糖醛腈乙酰酯的衍生方法。试验了5种毛细管柱,其中以OV-1701及FFAP两种所得分离效果最好,且给出较对称的峰形,测定时用肌醇作内标。应用此方法测定了7种单糖,即L-鼠李糖、D-岩藻糖、D-阿拉伯糖、D-木糖、D-甘露糖、D-葡萄糖及D-半乳糖,其分析响应信号与浓度之间均保持一定的线性关系。7种单糖的检出限(3S/N)均小于14μg。在一已知样品中分别加入单糖的标准后检测方法的回收率,测得结果在92.5%～102.5%之间,精密度试验所测得的相对标准偏差(n=5)均小于2.5%。

A comparative study on the GC determination of monosaccharides with capillary chromatographic column and pre-derivatization was reported. Among the 3 commonly used methods for derivatization, the method of transforming the monosaccharides to aldononitrile acetate in the presence of NH2OH· HCl （pyridine solution） and acetic anhydride, was chosen It was also shown that the capillary chromatographic columns of OV-1701 and FFAP were proved to be most efficient in separation and giving more symmetrical peak shape as compared with the other 3 columns tested. Inositol was used as internal standard in the determinations and 7 monosaccharides, i. e. , L-rhamnose, D-fucose, D-arabinose, D-xylose, D-mannose, D-glucose and D-galactose, were determined by the method. Linear relationships between values of analytical signals and concentration of the 7 monosaccharides were obtained with their linear regression equations given. Values of detection limit （3S/N） obtained were all less than 14μg. Standards of the 7 monosaccharides were added to a known sample and test for recovery was done, giving results in the range of 92. 5%-102. 5%. Results of RSD＇s （n=5） found by the precision test were all less than 2. 5%.