Peng Z G, Hidajat K, Uddin M S
Department of Chemical and Biomolecular Engineering, National University of Singapore, 10 Kent Ridge Crescent, Singapore 119260.
J Colloid Interface Sci. 2005 Jan 1;281(1):11-7. doi: 10.1016/j.jcis.2004.08.086.
Magnetic particles about 10 nm in size were prepared by chemical precipitation under nitrogen and used for the selective and sequential adsorption of bovine serum albumin (BSA) (pI = 4.7) and lysozyme (LSZ) (pI = 1.1) under different conditions, such as pH and initial protein concentration. The separation ratio of BSA over LSZ at pH 4.6 is about 5, which is about 1.5 times the separation ratio of LSZ over BSA at pH 11.0. Only 10% of the preadsorbed BSA could be displaced by the sequential adsorption of LSZ at pH 11.0. On the other hand, 60% of the preadsorbed LSZ was desorbed due to the sequential adsorption of BSA at pH 4.6. Over 50% desorption of BSA or LSZ could be achieved either by 0.5 M Na(2)HPO(4) or 0.5 M NaH(2)PO(4) after 2 h. Over 80% of the enzymatic activity of LSZ was preserved when it was desorbed from magnetic particles.
在氮气保护下通过化学沉淀法制备了尺寸约为10纳米的磁性颗粒，并用于在不同条件下（如pH值和初始蛋白质浓度）对牛血清白蛋白（BSA）（pI = 4.7）和溶菌酶（LSZ）（pI = 1.1）进行选择性和顺序吸附。在pH 4.6时，BSA相对于LSZ的分离比约为5，这是在pH 11.0时LSZ相对于BSA分离比的约1.5倍。在pH 11.0时，通过顺序吸附LSZ，只有10%的预吸附BSA能够被置换。另一方面，在pH 4.6时，由于顺序吸附BSA，60%的预吸附LSZ被解吸。2小时后，通过0.5 M Na₂HPO₄或0.5 M NaH₂PO₄可实现超过50%的BSA或LSZ解吸。当LSZ从磁性颗粒上解吸时，其超过80%的酶活性得以保留。
