亲水作用色谱法测定甜菊糖主要极性组分

Determination of Polar Components in Stevia by Hydrophilic Interaction Chromatography

以亲水作用色谱(HILIC)模式,建立一种强碱性阴离子交换分析柱(SAX)分离检测甜菊糖中甜菊糖甙、莱鲍迪甙C、莱鲍迪甙A的方法。根据吸附剂、吸附质的结构特点及物理特性,对分离机理进行初探,推测导致此机理的诱因可能为氢键、偶极作用等。与国标法相比,所建立的检测方法中色谱图杂质峰数目增多,主要物质分离度明显提高。甜菊糖甙、莱鲍迪甙C和莱鲍迪甙A的线性范围分别为0.056～5.600、0.032～3.200mg/mL和0.204～24.000mg/mL,R2分别为0.9991、0.9989和0.9992。3组分低、中、高3个质量浓度水平的加标回收率在95.8%～101.1%之间,相对标准偏差(n=6)均小于1.00%。该方法简单、灵敏、准确、重现性好,为准确分析甜菊糖主要极性组分提供了更加可靠的检测方法。

Based on hydrophilic interaction liquid chromatography（HILIC）,a method for the separation and determination of stevioside,rebaudiodside C and rebaudiodside A in stevia with strong anion-exchange column was established.According to the structural features and physical properties of the adsorbent and adsorbate,the separation mechanism of polar components in stevia was elucidated preliminarily.We speculated that the possible mechanism might be hydrogen bond and dipolar interaction.Compared with the national standard,the number of chromatographic peaks increased and the resolution of major substances revealed an obvious improvement.As a result,good linear correlations for stevioside,rebaudiodside C and rebaudiodside A were achieved in the concentration ranges of 0.056–5.600,0.032–3.200 mg/mL and 0.204–24.000 mg/mL,and the linear correlation coefficients（R2） were 0.9991,0.9989 and 0.9992,respectively.Recovery rates of three components at low,middle and high concentration levels were 95.8%–101.1%,with relative standard deviations less than 1.00%（n = 6）.The method is convenient,sensitive,accurate and reproducible.It can provide a reliable way of determining polar components in stevia.