Batzli Kiersten M, Love Brian J
Department of Materials Science and Engineering, University of Michigan, 2300 Hayward St, Ann Arbor, MI 48109, United States.
Department of Materials Science and Engineering, University of Michigan, 2300 Hayward St, Ann Arbor, MI 48109, United States; Macromolecular Science and Engineering Research Center, University of Michigan, 2300 Hayward St, Ann Arbor, MI 48109, United States; Department of Biomedical Engineering and Biologic and Materials Sciences (Dentistry), University of Michigan, 2300 Hayward St, Ann Arbor, MI 48109, United States.
Mater Sci Eng C Mater Biol Appl. 2015 Mar;48:103-11. doi: 10.1016/j.msec.2014.11.056. Epub 2014 Nov 24.
Modern technology demands ever smaller and more efficient nanoparticles, wires and networks. The natural tendency for amyloid proteins to form fibrillar structures is leveraged in creating high aspect ratio, nano-sized protein fibers as scaffolds for metallized nanowires. The morphology of fibrils is influenced by induced strain during denaturing and early aggregation and subsequent fibril deposition with platinum leads to controlled catalyst surfaces based on the initial protein precipitate. Here we have created insulin fibrils with varying morphologies produced in the presence of heat and strain and investigated their metallization with platinum by TEM. The catalytic activity of the metal-coated protein fibrils was resolved by tracking the reaction kinetics of the conversion of 4-nitrophenol to 4-aminophenol in the presence of the produced nanowires using UV-Vis spectroscopy. The effects of fibril morphology and temperature on the pseudo-first-order kinetics of conversion are investigated. Conversion to 4-aminophenol occurs on the order of minutes and is independent of temperature in the range tested (7 to 20°C). Two regimes of conversion are identified, an early higher rate, followed by a slower later rate.
现代技术要求纳米颗粒、纳米线和网络越来越小且效率越来越高。淀粉样蛋白形成纤维状结构的自然倾向被用于制造高纵横比的纳米级蛋白质纤维，作为金属化纳米线的支架。原纤维的形态受到变性和早期聚集过程中诱导应变的影响，随后用铂进行原纤维沉积会基于初始蛋白质沉淀形成可控的催化剂表面。在这里，我们制备了在加热和应变条件下产生的具有不同形态的胰岛素原纤维，并通过透射电子显微镜研究了它们用铂进行金属化的情况。使用紫外-可见光谱法跟踪所制备的纳米线存在下4-硝基苯酚转化为4-氨基苯酚的反应动力学，从而解析了金属包覆蛋白质原纤维的催化活性。研究了原纤维形态和温度对转化的准一级动力学的影响。转化为4-氨基苯酚的过程在几分钟内完成，并且在所测试的温度范围（7至20°C）内与温度无关。确定了两种转化机制，早期速率较高，随后速率较慢。
