高效离子交换色谱法测定半乳糖、葡萄糖、乳糖及低聚半乳糖含量

Determination of Galactose, Glucose, Lactose and Galacto-Oligosaccharide by High Performance Ion Exchange Chromatography

建立离子色谱法定量测定以乳糖为原料、使用伊半乳糖苷酶生产的低聚半乳糖产品的方法。样品前处理过程中用体积稀释法代替质量稀释法，采用高效CarboPac PA20阴离子交换色谱柱和积分安培法检测，并对淋洗液组成进行优化。优化后的方法加标回收率90．58％-99．45％，相对标准偏差为3．54％。半乳糖、葡萄糖、乳糖的方法检出限分别为0．24、0．59、0．75μg／g。半乳糖和葡萄糖在0．2～7μg／mL、乳糖在0．6～10μg／mL的范围内，其质量浓度与峰面积线性关系良好，相关系数在0．9992～0．9999之间。用此方法测定6种原料低聚半乳糖，目标组分总含量为95．84％～101．19％。

A method was established to determine galacto-oligosaccharide （GOS）, synthesized with fl-galactosidase using lactose as the precursor, by ion exchange chromatography. The pre-treatment of samples was achieved through volume dilution instead of gravimetric dilution. CarboPac PA20 anion exchange column and pulsed amperometric detector were used to determine the contents of GOS. The recovery of the proposed method was 90.58%-99.45% and the relative standard deviation was 3.54%. The detection limits for gluctose, galactose and lactose were 0.24, 0.59 and 0.75 μg/g, respectively. The method presented linear correlation coefficients between 0.999 2 and 0.999 9 when the concentrations of gluctose and galactose were in the range of 0.2-7.0 μg/mL and lactose was 0.6-10 μg/mL. Six GOS samples were determined by this method to contain galactose, glucose, lactose and GOS in the range of 95.84%-101.19%.