Wu Yanwei, Xiang Bingren, Yang Jin, Fu Jingjuan, Jiang Jianhua
Department of Chemistry, Wuhan University, Wuhan, China.
J Chromatogr Sci. 2005 Apr;43(4):169-73.
New microporous particles with large pore size (mean pore diameter of 820 nm) are successfully prepared from a mixture of cellulose and konjac glucomannan (RC-KGM3) in 1.5 M NaOH-0.65 M thiourea aqueous solution by coagulating with 5 weight percentage (wt%) CaCl(2), and then 2 wt% HCl aqueous solution. A preparative size-exclusion chromatographic (SEC) column packed with the gel particles is used for the fractionation of a dextran in water. The exclusion limit and fractionation range of the stationary phase are molecular masses of 125 yen 104 g/mol and 5.6 yen 104 to 125 yen 104 g/mol, respectively. The dextran [dextran 50, weight-average molecular mass (M(w)) = 40.1 yen 104 g/mol, polydispersity index (d) = 3.5] is fractionated by the preparative SEC column to obtain six fractions, and four of them are refractionated twice by the same preparative SEC column. The refractionated samples F-3-3 and F-4-3 are characterized by analytical SEC combined with laser light scattering and light scattering to obtain M(w) of 91.8 and 61.9 yen 104 g/mol, as well as d of 1.3 and 1.4, respectively. The results indicate that the fractions having narrow molecular mass distribution are satisfactorily prepared with the SEC column. The described SEC column can be successfully used to fractionate polymers in aqueous solution.
通过在1.5 M氢氧化钠-0.65 M硫脲水溶液中，用5重量百分比（wt%）的氯化钙进行凝固，然后用2 wt%的盐酸水溶液处理，成功地从纤维素和魔芋葡甘露聚糖的混合物（RC-KGM3）中制备出了具有大孔径（平均孔径为820纳米）的新型微孔颗粒。将填充有凝胶颗粒的制备型尺寸排阻色谱（SEC）柱用于水中葡聚糖的分级分离。固定相的排阻极限和分级分离范围分别为分子量125×10⁴ g/mol和5.6×10⁴至125×10⁴ g/mol。葡聚糖[葡聚糖50，重均分子量（M(w)）= 40.1×10⁴ g/mol，多分散指数（d）= 3.5]通过制备型SEC柱进行分级分离，得到六个级分，其中四个级分通过同一制备型SEC柱进行了两次再分级分离。对再分级分离后的样品F-3-3和F-4-3，通过结合激光光散射和光散射的分析型SEC进行表征，得到M(w)分别为91.8和61.9×10⁴ g/mol，以及d分别为1.3和1.4。结果表明，使用该SEC柱可以令人满意地制备出具有窄分子量分布的级分。所描述的SEC柱可成功用于水溶液中聚合物的分级分离。
