Key Laboratory of Synthetic and Biological Colloids, Ministry of Education, School of Chemical and Material Engineering, Jiangnan University, 1800 Lihu Road, Wuxi, Jiangsu Province 214122, P. R. China.
J Mater Chem B. 2021 Oct 20;9(40):8464-8471. doi: 10.1039/d1tb01532j.
Selective removal of an organic compound in the coexistence of other constituents is a great challenge in separation and purification processes. In this work, bovine serum albumin (BSA)-stabilized iridium nanoparticles (IrNPs) were prepared a facile one-step precipitation method. The resulting BSA-IrNPs were comprehensively characterized by TEM, XRD, XPS, UV-vis, FT-IR, and fluorescence spectroscopy as well as circular dichroism spectrometry. It was found that the nanoparticles with an average diameter of 3.6 nm were embedded in the aggregated protein matrix and the structure of the coating agent was maintained well on the surface of nanoparticles. The as-prepared nanozymes (BSA-IrNPs) exhibit strong peroxidase-like activity and can selectively catalyse the degradation of cationic compounds by HO in the coexistence of other inorganic or organic substances at room temperature. Interestingly, the degradation of amino acids could be precisely controlled by adjusting the pH above or below their isoelectric points. The catalytic selectivity of BSA-IrNPs should be ascribed to the anchoring effect between the amidogen-containing molecules and BSA through electrostatic adsorption. The nanozyme also exhibits excellent reusability as it can be readily recycled from solution by static settlement or centrifugation. Therefore, BSA-IrNPs have great potential for the selective removal of cationic compounds and amino acids in a complex matrix.
在分离和纯化过程中，从共存的其他成分中选择性地去除有机化合物是一个巨大的挑战。在这项工作中，通过简便的一步沉淀法制备了牛血清白蛋白（BSA）稳定的铱纳米粒子（IrNPs）。通过 TEM、XRD、XPS、UV-vis、FT-IR 和圆二色性光谱以及荧光光谱对所得的 BSA-IrNPs 进行了全面表征。结果发现，平均直径为 3.6nm 的纳米粒子嵌入在聚集的蛋白质基质中，并且在纳米粒子表面上很好地保持了涂层剂的结构。所制备的纳米酶（BSA-IrNPs）表现出很强的过氧化物酶样活性，并且可以在室温下在共存的其他无机或有机物质中选择性地催化阳离子化合物通过 HO 的降解。有趣的是，通过调节 pH 值高于或低于其等电点，可以精确控制氨基酸的降解。BSA-IrNPs 的催化选择性应归因于通过静电吸附在含酰胺基分子和 BSA 之间的锚固效应。纳米酶还表现出良好的可重复使用性，因为它可以通过静态沉降或离心从溶液中容易地回收。因此，BSA-IrNPs 有望用于复杂基质中阳离子化合物和氨基酸的选择性去除。
