Glucose Biosensor Based on Poly-Lithium Benzenetricarboxylic Acid and Multi-walled Carbon Nanotubes Composite Film

A novel organic metal framework compound-lithium 1, 3, 5-benzenetricarboxylic acid (Li-BTC) was polymerized on the bare glassy carbon electrode by electropolymerization method. Then, Nafion/GO(x)/MWNTs/poly-Li-BTC/GC electrode was fabricated by drop coating method. The morphology of the composite film containing MWNTs and poly-Li-BTC was characterized by scanning electron microscopy (SEM). The electrochemical performance of the modified electrode was investigated by cyclic voltammetry (CV) and electrochemical impedance spectroscopy (EIS). The results showed the composite film increased the effective surface area and improved electrocatalytic activity of GC electrode. The electrochemical performance of Nafion/GO(x)/MWNTs/poly-Li-BTC/GC electrode for detection of glucose was investigated by cyclic voltammetry and chronoamperometry. The experiment results showed that the linear range for the detection of the glucose was from 0.02 to 1.56 mmol/L with a correlation coefficient of 0.9992, detection limit of 5.1 mu mol/L (S/N=3:1). The Michaelis constant was 0.832 mmol/L and recovery rate was from 96.5% to 100.3% for the modified electrode. The prepared glucose biosensor has good repeatability, reproducibility, selectivity and stability, and can be applied to determine the glucose content in glucose injection samples.