Max Planck Institute for Intelligent Systems , Heisenbergstrasse 3 , 70569 Stuttgart , Germany.
Institute of Physical Chemistry , University of Stuttgart , Pfaffenwaldring 55 , 70569 Stuttgart , Germany.
ACS Nano. 2019 May 28;13(5):5810-5815. doi: 10.1021/acsnano.9b01408. Epub 2019 Apr 9.
Catalytically active colloids are model systems for chemical motors and active matter. It is desirable to replace the inorganic catalysts and the toxic fuels that are often used with biocompatible enzymatic reactions. However, compared to inorganic catalysts, enzyme-coated colloids tend to exhibit less activity. Here, we show that the self-assembly of genetically engineered M13 bacteriophages that bind enzymes to magnetic beads ensures high and localized enzymatic activity. These phage-decorated colloids provide a proteinaceous environment for directed enzyme immobilization. The magnetic properties of the colloidal carrier particle permit repeated enzyme recovery from a reaction solution, while the enzymatic activity is retained. Moreover, localizing the phage-based construct with a magnetic field in a microcontainer allows the enzyme-phage-colloids to function as an enzymatic micropump, where the enzymatic reaction generates a fluid flow. This system shows the fastest fluid flow reported to date by a biocompatible enzymatic micropump. In addition, it is functional in complex media including blood, where the enzyme-driven micropump can be powered at the physiological blood-urea concentrations.
催化胶体是化学马达和活性物质的模型体系。理想情况下，需要用生物相容性的酶反应来替代常用的无机催化剂和有毒燃料。然而，与无机催化剂相比，酶包覆胶体往往表现出较低的活性。在这里，我们展示了通过基因工程改造的能够将酶结合到磁珠上的 M13 噬菌体的自组装，确保了高且局部的酶活性。这些噬菌体修饰的胶体为定向酶固定化提供了蛋白质环境。胶体载体颗粒的磁性允许从反应溶液中重复回收酶，同时保留酶活性。此外，通过磁场将基于噬菌体的结构定位于微容器中，可以使酶-噬菌体-胶体作为酶微泵起作用，其中酶反应产生流体流动。与迄今报道的其他生物相容性酶微泵相比，该系统显示出最快的流体流动速度。此外，它在包括血液在内的复杂介质中也具有功能，在血液生理尿素浓度下，酶驱动的微泵可以提供动力。
