Key Laboratory of Molecular Medicine and Biotherapy, School of Life Science, Beijing Institute of Technology, 5 South Zhongguancun Street, Beijing, 100081, China.
Key Laboratory of Molecular Medicine and Biotherapy, School of Life Science, Beijing Institute of Technology, 5 South Zhongguancun Street, Beijing, 100081, China.
Anal Chim Acta. 2020 Dec 15;1140:228-235. doi: 10.1016/j.aca.2020.10.024. Epub 2020 Oct 16.
Construction of new enzyme reactor based on aptamer functionalized magnetic nanoparticles conjugated organic framework (COF) for acetylcholinesterase immobilization has been an enabling endeavor in this work. The aptamer against acetylcholinesterase was selected through a method based on capillary electrophoresis in one round. A new magnetic COF material rich of carboxyl groups was firstly synthesized, and its surface was then modified with the selected aptamer through covalently linking. Acetylcholinesterase was immobilized to fabricate the enzyme reactor FeO@COF-Apt-AChE through the high affinity and specificity with its binding aptamer. The as constructed enzyme reactor was comprehensively characterized and the key factors that affected its catalysis efficiency were investigated in detail. Owing to the surface modification of the magnetic COF materials by aptamer for acetylcholinesterase immobilization, the immobilized enzyme exhibited improved substrates affinity. What's more, good reusability (more than 8 times) and prolonged stability (enzyme activity still kept at 90% after 42 days) were also achieved. Finally, the enzyme reactor could be applied in AChE inhibitors screening, which expanded its application capability. The proposed protocol not only paves a new way for fabrication of novel aptamer functionalized magnetic COF materials as enzyme reactors, but also indicates a broadened application of the integration of aptamer and its enzyme.
基于适配体功能化磁性纳米粒子偶联有机框架（COF）构建新型酶反应器用于乙酰胆碱酯酶固定化是本工作的一项重要进展。通过一轮基于毛细管电泳的方法筛选出了针对乙酰胆碱酯酶的适配体。首先合成了一种富含羧基的新型磁性 COF 材料，然后通过共价连接将筛选出的适配体修饰到其表面。通过与结合适配体的高亲和力和特异性，将乙酰胆碱酯酶固定化制备酶反应器 FeO@COF-Apt-AChE。对构建的酶反应器进行了全面表征，并详细研究了影响其催化效率的关键因素。由于通过适配体对磁性 COF 材料进行了表面修饰，固定化酶表现出了提高的底物亲和力。此外，还实现了良好的可重复使用性（超过 8 次）和延长的稳定性（42 天后酶活性仍保持在 90%）。最后，该酶反应器可用于 AChE 抑制剂的筛选，从而扩展了其应用能力。该方案不仅为新型适配体功能化磁性 COF 材料作为酶反应器的制备开辟了新途径，而且表明了适配体及其酶的结合具有更广泛的应用前景。
