Lin Jiang-Jen, Wei Jiun-Chiou, Tsai Wei-Cheng
Institute of Polymer Science and Engineering, National Taiwan University, Taipei 10667, Taiwan.
J Phys Chem B. 2007 Aug 30;111(34):10275-80. doi: 10.1021/jp072973s. Epub 2007 Aug 9.
We have developed a process to incorporate the model protein, bovine serum albumin (BSA), into the layered spacing of swelled mica. By a stepwise intercalation, the sodium form of synthetic fluorinated mica (Mica) was first exchanged with the poly(oxyalkylene)-diamine salts (POA-amine) through an ionic exchange reaction and then the BSA embedment. The first step of the Mica space expansion from the pristine 12 A to 18-93 A was affected by hydrophobic POP-amines (POP2000 of 2000 g/mol and POP4000 of 4000 g/mol M(w)) and the hydrophilic POE2000 that intercalated Na+-Mica to afford different basal spacing (39, 93, and 18 A, respectively). The POA modification was necessary for the BSA intercalation and resulted in an uncompressed form of protein conformation in the layered confinement (XRD d spacing = 60-71 A). For comparison, direct intercalation rendered only low d spacing (30 A), in which BSA was embedded in a compressed conformation. The BSA-mica complexes were characterized by X-ray, TGA, and solution analyses. The stepwise process provides a new method for embedding large protein molecules into the clay layered structure generating protein/layered silicate complexes.
我们已经开发出一种将模型蛋白牛血清白蛋白（BSA）纳入膨胀云母层间距的方法。通过逐步插层，首先通过离子交换反应将合成氟化云母（云母）的钠形式与聚（氧化烯） - 二胺盐（POA - 胺）进行交换，然后进行BSA嵌入。云母空间从原始的12 Å扩展到18 - 93 Å的第一步受到疏水性POP - 胺（分子量为2000 g/mol的POP2000和4000 g/mol的POP4000）和亲水性POE2000的影响，它们插入Na + - 云母中以提供不同的基面间距（分别为39、93和18 Å）。POA修饰对于BSA插层是必要的，并且在层状限制中产生了未压缩形式的蛋白质构象（XRD d间距 = 60 - 71 Å）。相比之下，直接插层仅产生低d间距（30 Å），其中BSA以压缩构象嵌入。通过X射线、热重分析（TGA）和溶液分析对BSA - 云母复合物进行了表征。该逐步过程提供了一种将大蛋白质分子嵌入粘土层状结构中以生成蛋白质/层状硅酸盐复合物的新方法。
