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

Abstract

<p indent="0mm">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 <sc>0–35 μM,</sc> 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.