Abstract: To prepare the cellulose-based chromatography matrix with uniform size, a cross-flow microchannel chip was used to control the droplet size of cellulose solution and then the microdroplets were solidified to obtain the monodisperse cellulose beads.In the present work, ionic liquid,[EMIM]MP, was used to dissolve the microcrystalline cellulose as water phase and sunflower oil was used as oil phase.The effects of cellulose concentration, surfactant addition, flow rates of oil phase and water phase were investigated.The optimized preparation condition was 2% cellulose solution as water phase, flow rate of water phase of 6 μl·min^-1 and flow rate of oil phase of 200 μl·min^-1.The microdroplets of cellulose solution thus obtained could be about 100 μm with the variation coefficient less than 0.2.After solidification and regeneration, cellulose beads were obtained with good sphericity.Wet density of beads was 1.019 g·ml^-1, porosity was 94.6%, and mean size was about 105.5 μm.The cellulose beads were coupled with DEAE ligand and used as weak anion-exchange resin.The ion exchange capacity was 123.3 μmol·g^-1.Static adsorption and adsorption kinetics were studied.The results showed that saturated adsorption capacity for bovine serum albumin could reach 220 mg·g^-1, and the effective diffusion coefficient was 1.8×10^-11 m²·s^-1, which showed potential application for protein separation.

Key words: microfluidic chip, cellulose, microsphere, ionic liquid, ion-exchange resin

摘要： 为了满足层析介质对粒径单分散的要求,利用十字型微通道的聚焦效应,形成粒径均一的纤维素微液滴,经固化成纤维素微球,再偶联配基制成了纤维素层析介质。以离子液体1-乙基-3-甲基咪唑甲基磷酸直接溶解微晶纤维素为水相,葵花籽油为油相,考察了微通道内微液滴的形成条件,优化了纤维素浓度、分散剂浓度、油水两相流速等因素,得到粒径约100 μm的纤维素微液滴,CV值小于0.2。微液滴固化再生,得到球形度良好的纤维素微球,湿真密度1.019 g·ml^-1,孔度94.6%,体均粒径105.5 μm;进一步偶联DEAE配基,制得了离子交换层析介质,离子交换容量为123.3 μmol·g^-1,牛血清白蛋白的饱和吸附容量Q_m达到220 mg·g^-1,有效扩散系数D_e为1.8×10^-11m²·s^-1,体现出较好的蛋白质吸附性能。

关键词: 微流芯片, 纤维素, 微球, 离子液体, 离子交换介质