Rodionov Ilya A, Grinberg Natalia V, Burova Tatiana V, Grinberg Valery Ya, Lozinsky Vladimir I
A.N. Nesmeyanov Institute of Organoelement Compounds, Russian Academy of Sciences, Vavilov Street 28, 119991 Moscow, Russian Federation.
Soft Matter. 2015 Jun 28;11(24):4921-31. doi: 10.1039/c4sm02814g.
Freeze-thaw processing of bovine serum albumin (BSA) aqueous solutions, which contain also the additives of denaturants (urea in this case) and thiol-bearing reductants [cysteine (Cys) in this case] leads to the formation of wide-pore cryogels. The properties and porous morphology of these spongy gel matrices were demonstrated to depend on the initial concentration of all precursors and on the freezing/frozen storage temperature. The optimum conditions for preparing such BSA-based cryogels were found to be as follows: [BSA] = 3-5 g dL(-1), [urea] = 0.5-2.0 mol L(-1), [Cys] = 0.01 mol L(-1), and freezing temperatures in the range of -15 to -20 °C. The size of gross pores in thus prepared cryogels is ∼50-150 μm. The spatial network of BSA-cryogels was shown to be cross-linked chemically via interchain disulfide bridges. The significant role of hydrophobic interactions in the stabilization of 3D networks of these cryogels is inferred, as well as the supposition about the relay-race sequence mechanism of the intermolecular disulfide cross-link formation is made.
对含有变性剂添加剂（在这种情况下为尿素）和含硫醇还原剂（在这种情况下为半胱氨酸）的牛血清白蛋白（BSA）水溶液进行冻融处理，会导致形成大孔冷冻凝胶。已证明这些海绵状凝胶基质的性质和多孔形态取决于所有前体的初始浓度以及冷冻/冻存温度。制备此类基于BSA的冷冻凝胶的最佳条件如下：[BSA] = 3 - 5 g dL⁻¹，[尿素] = 0.5 - 2.0 mol L⁻¹，[半胱氨酸] = 0.01 mol L⁻¹，冷冻温度范围为 - 15至 - 20°C。如此制备的冷冻凝胶中的大孔尺寸约为50 - 150μm。BSA冷冻凝胶的空间网络显示通过链间二硫键进行化学交联。推断出疏水相互作用在这些冷冻凝胶的三维网络稳定中的重要作用，同时提出了分子间二硫键交联形成的接力序列机制的假设。
