硫酸酯化赋予了多糖独特的抗病毒、抗凝血等生物活性，但其活性严格受控于分子量大小。然而，用于检测硫酸多糖分子量的方法仍然采用葡聚糖为标准品，必然出现对活性硫酸多糖分子量的误判。本文通过对比标准葡聚糖和葡聚糖硫酸酯的特征粘性参数，观察两种多糖的流变力学差异性；并采用改良Mark-Houwink-Sakurada(MHS)模型和常规柱层析技术探讨硫酸酯化对多糖分子量测定的干扰性。结果发现：葡聚糖与葡聚糖硫酸酯表现出不同的流体力学性质，葡聚糖浓度与比浓粘度关系式斜率为正，而葡聚糖硫酸酯浓度与其比浓粘度关系式斜率为负；改良MHS模型发现，两种多糖的DB方程式特性常数出现明显差异；凝胶柱层析分析发现，如果采用葡聚糖为标准品，葡聚糖硫酸酯的分子量会远大于其真实值。以上结果说明，硫酸酯化会对多糖的流变特性产生影响，是造成常规检测方法误判硫酸多糖分子量的根本原因。

Sulfate esterification facilitates a number of biological activities, such as antiviral and anticoagulant effects, that are unique to polysaccharides. Its activity is strictly controlled by molecular weight. However, dextran is widely used as the standard substance in the determination of the molecular weights of sulfated polysaccharides and its use inevitably leads to the misjudgment of active sulfated polysaccharide molecular weight. The rheological mechanic differences between standard dextran and dextran sulfate were observed by comparing the characteristic viscous parameters of the two substances. An improved Mark-Houwink-Sakurada (MHS) model and conventional column chromatography were used to analyze the interference of sulfate esterification in the detection of polysaccharide molecular weight. The results showed that dextran and dextran sulfate have different fluid mechanics. The gradient of the correlation equation for dextran concentration and its reduced viscosity was positive, whereas that for dextran sulfate was negative. Improved MHS model also demonstrated significant differences in the specific coefficients in the DB equations of the two polysaccharides. The results of column chromatography showed that the molecular weight detected with dextran sulfate was far greater than the true value if dextran was used as the standard substance. In summary, sulfate esterification may change the rheological behavior of polysaccharides and is thus a fundamental cause for the misjudgment of polysaccharide molecular weight measured using normal detection methods.

国家海洋公益项目（201205022-6）；厦门市科技计划项目（3502Z20143019）