以离子液[Emim]Ac为溶剂，采用挤球法制备壳聚糖/纤维素硫酸酯（CHT-CS）复合小球，探索制备条件，并用FT-IR、SEM和XRD对其进行表征。将复合小球用于吸附牛血清蛋白（BSA），考察影响CHT-CS吸附BSA的因素。结果表明：制备复合小球的最佳条件是纤维素酸酯的取代度为0.58，复合原料液的浓度为5%，壳聚糖:纤维素硫酸酯为1:1；纤维素硫酸酯和壳聚糖在制备过程中发生了复杂的相互作用，形成了结构稳定，表面和内部均存在大量沟壑和孔洞的小球；所制备的复合小球对BSA的最大平衡吸附量达到157 mg/g，高于其他壳聚糖复合材料；当BSA初始浓度1 mg/mL、溶液pH为5左右，小球对BSA的吸附量最大；一定范围内增加小球投加量在可增大BSA吸附量。本研究结果为分离纯化BSA和CHT-CS复合小球固定化酶等方面的应用提供了参考。

Composite beads of chitosan and cellulose sulfate (CHT-CS) were prepared by squeezing with ionic liquid [Emim]Ac as the solvent. The preparation conditions were optimized, and the CHT-CS beads were characterized by fourier transform infrared spectroscopy (FT-IR), scanning electron microscope (SEM), and X-ray diffraction (XRD) measurement. The adsorption capacity of CHT-CS beads for bovine serum album (BSA) was evaluated, and the conditions affecting BSA adsorption were investigated. The results indicated that the optimum conditions for CHT-CS bead preparation were a cellulose sulfate substitution degree of 0.58, a composite raw material concentration of 5% (m/V), and a CS/CHT ratio of 1:1. A complex interaction between cellulose sulfate and chitosan occurred during the preparation of the composite beads, providing structural stability with many gaps and holes on the surface and in the interior of the beads. The maximum BSA adsorption capacity of the composite beads (157 mg/g) was achieved when the initial concentration of BSA was 1 mg/mL and the pH was 5. The adsorption capacity increased with the amount of CHT-CS beads, within a certain range. These results may potentially provide a reference for the separation and immobilization of BSA.

国家自然科学基金资助项目（31071505，31371743）