Cu-Based Conductive MOF Grown in situ on Cu Foam as a Highly Selective and Stable Non-Enzymatic Glucose Sensor.

Qin Hu,Guang-Xiang Liu,Hai-Ying Wang,Jing-Yuan Ge,Xiao-Feng Wang,Jie Qin,Guang-Ying Ran,Jian-Ping Ma,Qiang Wang

doi:10.3389/fchem.2021.786970

Abstract

A non-enzymatic electrochemical sensor for glucose detection is executed by using a conductive metal–organic framework (MOF) Cu-MOF, which is built from the 2,3,6,7,10,11-hexahydroxytriphenylene (HHTP) ligand and copper acetate by hydrothermal reaction. The Cu-MOF demonstrates superior electrocatalytic activity for glucose oxidation under alkaline pH conditions. As an excellent non-enzymatic sensor, the Cu-MOF grown on Cu foam (Cu-MOF/CF) displays an ultra-low detection limit of 0.076 μM through a wide concentration range (0.001–0.95 mM) and a strong sensitivity of 30,030 mA μM−1 cm−2. Overall, the Cu-MOF/CF exhibits a low detection limit, high selectivity, excellent stability, fast response time, and good practical application feasibility for glucose detection and can promote the development of MOF materials in the field of electrochemical sensors.

Highlights

Glucose is the direct source of energy for the human body and is indispensable for human functional movement
We developed a high-performance nonenzymatic electrochemical glucose sensor by in situ growth of conductive copper metal–organic framework (MOF) on copper foam (CF) using a simple one-step hydrothermal method
The Scanning electron microscopy (SEM) image of Cu-MOF/CF (Figure 1A) and Transmission electron microscopy (TEM) image for sample obtained by sonicating Cu-MOF/CF (Figure 1B) clearly show the rod-like morphology of Cu-MOF

Summary

INTRODUCTION

Glucose is the direct source of energy for the human body and is indispensable for human functional movement. The common solutions to improve the conductivity of materials are coupling MOFs with conductive materials such as carbon black and electroconductive rubber These methods increase the series resistance and lead to reduction in the surface area, blocking the active sites and hindering the diffusion of target molecules (Zhu et al, 2016; Ko et al, 2018). We developed a high-performance nonenzymatic electrochemical glucose sensor by in situ growth of conductive copper MOF on copper foam (CF) using a simple one-step hydrothermal method. Under the optimal conditions of each parameter value, the prepared electrode Cu-MOF/CF showed excellent electrocatalytic activity for glucose oxidation at alkaline pH with high sensitivity, low detection limit, wide linear detection range, short response time, and excellent stability. The geometric area of working electrodes was controlled at 0.2 × 0.2 cm−2 in all tests (Supplementary Scheme S1)

AND DISCUSSION

DATA AVAILABILITY STATEMENT

Findings

CONCLUSION