Abstract: A new mixed-mode absorbent，named B-DVS-MI，with functional ligand 2-mercaptoimidazole was prepared and used for separation of immunoglobulin from bovine colostrums.There could exist hydrophobic，electrostatic and thiophilic interactions between B-DVS-MI and the adsorbate.Divinylsulfone activation and ligand coupling processes on the agarose beads were employed and optimized，resulting in activation density of 100 μmol·ml-1 and ligand density of 65 μmol·ml-1.The adsorption isotherm and kinetics for B-DVS-MI - bovine colostrum immunoglobulin system were measured and analyzed.The results showed that new adsorbent was of high capacity of immunoglobulin［127.6 mg·(g gel)-1］，and of typical salt-independent properties.Its adsorption behaviors were significantly influenced by pH，so，with pH adjustment effective adsorption and elution could be achieved.The chromatographic conditions were optimized to separate effectively immunoglobulin from bovine colostrum powder，and product purity up to 95%.As a conclusion，bovine colostrum immunoglobulin could be effectively separated by mixed-mode adsorption chromatography，which could be a new way for comprehensive utilization of bovine colostrums.

Key words: mixed-mode chromatography, 2-mercaptoimidazole, divinylsulfone activation, immunoglobulin, bovine colostrums

摘要： 针对免疫球蛋白的分离纯化，设计和制备了以2-巯基咪唑为功能配基的新型混合模式层析介质B-DVS-MI，兼有疏水、静电和亲硫作用。采用二乙烯基砜活化法，优化了琼脂糖微球基质的活化反应和配基偶联条件，活化密度达100 μmol·ml-1以上，2-巯基咪唑配基密度达65 μmol·ml-1。将该介质用于从牛初乳蛋白粉中分离免疫球蛋白，考察了B-DVS-MI对牛初乳免疫球蛋白的静态和动态吸附性能，结果表明介质吸附容量达到127.6 mg·(g介质)-1，具有非盐依赖的吸附特性，且pH显著影响吸附性能，通过调节pH可实现高效吸附和洗脱。确定了合适的层析分离条件，从牛初乳蛋白粉中直接分离牛初乳免疫球蛋白，纯度达95%以上。结果充分说明，制备的新型混合模式层析介质B-DVS-MI是一种高效分离免疫球蛋白的分离介质。

关键词: 混合模式层析, 2-巯基咪唑, 二乙烯基砜活化, 免疫球蛋白, 牛初乳