金属卟啉基共价-有机框架/炭黑复合修饰电极同时检测鸟嘌呤、6-甲基嘌呤和腺嘌呤

Facile construction of carbon-loaded metalloporphyrin-based covalent-organic framework composites for simultaneous electrochemical detection of guanine,N6-methyladenine and adenine

本文采用一步溶剂热法合成了系列金属卟啉基共价-有机框架/炭黑复合材料(COF-366/CB),用于修饰玻碳电极以检测鸟嘌呤(G)、N6-甲基腺嘌呤(N6-mA)和腺嘌呤(A).研究发现,卟啉中心的金属离子对复合材料的传感性能有着重要影响,当中心金属离子为Co(Ⅱ)时,COF-366-Co/CB修饰电极表现出灵敏度高、选择性好、稳定性强的检测性能.当单独检测G、N6-mA和A时,线性范围分别为0~40、0~24和0~35μM,检测限分别为0.07、0.09和0.06μM.实验结果表明,COF-366-Co/CB的优异传感性能可能是由于其良好的导电性、高的比表面积和强吸附能力.同时,COF-366-Co/CB还能够同时检测G、N6-mA和A,互不干扰.进一步研究表明,G、N6-mA或A分子首先通过氢键相互作用被吸附到COF-366-Co/40%CB的表面,从而发生氧化还原反应.本工作为嘌呤类化合物的定量检测提供了一种简单的方法,也为COF在电化学传感领域的应用开发提供了新的手段.

In this paper,a series of carbon-loaded metalloporphyrin-based covalent organic framework(COF)composites were synthesized by one-step solvothermal method.The experimental results show that the loading amount of carbon black(CB)has a significant effect on the surface area and conductivity of COF composites.Thereafter,the composites were developed as electrochemical sensors to detect guanine(G),N6-methyladenine(N6-mA)and adenine(A).It has shown that the metal ions accommodated in the center of porphyrin units have a significant impact on the sensing performance.Among them,COF-366-Co/CB has high selectivity,strong stability,and good repeatability,and can detect G,N6-mA,and A simultaneous without interference with each other.When these purine molecules were detected separately,the linear ranges for G,N6-mA,and A are 0-40,0-24,and 0-35μM,respectively.Further studies show that the excellent sensing performance of COF-366-Co/CB may be raised from the effective host guest interaction between purine molecule and COF skeleton.This work provides a simple method for the quantitative detection of purine,and also opens up a new way to expand the application of COFs in the field of electrochemical sensing.