多糖类辅料分子质量及分子质量分布的研究方法进展

药用辅料的功能性指标会影响药物制剂的稳定性和一致性，在药用辅料的质量研究中日益引起人们的重视，多糖属于药用辅料中的一种，其应用日趋广泛。因多糖类辅料的分子质量及其分布是影响其功能性的关键指标，需对其分子质量及其分布进行准确测定。本文对多糖类辅料的分子质量及其分布测定方法进行归纳总结，主要包括黏度法、凝胶渗透色谱法、凝胶渗透色谱与光散射法联用、场流分离法等。黏度法只能得到黏均分子质量，凝胶渗透色谱法可得到相对分子质量及其分布，当其联用光散射法时，可测定绝对分子质量及其分布，场流分离法也可得到绝对分子质量及其分布，但在药用辅料测定中应用有限。

Functionality related characteristics (FRCs) of pharmaceutical excipients will affect the stability and consistency of the pharmaceutical preparations,and have attracted much attention to the quality control of pharmaceutical excipients.Polysaccharides is one kind of pharmaceutical excipients.Its application has become increasingly popular.Molecular mass and its distribution of polysaccharide excipients are the key factors that affect FRCs.Thus these key factors should be measured accurately.In this review,the determination methods for molecular mass and molecular mass distribution of polysaccharide excipients were summarized,including viscosity method,gel permeation chromatography (GPC),GPC combined with laser light scattering method and field flow separation method etc.Viscosity method can only generate viscosity-average molecular mass,molecular mass values and their distribution can be obtained by GPC,the absolute molecular mass and molecular mass distribution can be obtained by GPC combined with laser light scattering method or field flow fractionation (FFF) method while FFF method is not widely used in pharmaceutical excipients.