Enzymatic Electrochemical Biosensor from Eu‐Doped SnO₂ Embedded in MXene for High Performance Sensing Lactate

Abstract

In this work, Eu3+‐doped SnO2 nanoparticles are prepared and embedded into MXene (Ti3C2) laminates, and Ti3C2@Eu‐SnO2 composites are obtained. Cyclic voltammetry (CV) and scanning electron microscopy (SEM) characterization show that the composites have excellent electrochemical properties and unique morphology. The electrochemical impedance spectroscopy (EIS) and Fourier transform infrared spectrometer (FTIR) results of lactate oxidase (Lox) immobilized on Ti3C2@Eu‐SnO2 indicate that Eu‐SnO2, Ti3C2, and Lox have a good hybrid coordination and biocompatibility. The enzymatic electrochemical biosensor constructed with Ti3C2@Eu‐SnO2/Lox on glassy carbon electrode (GCE) reveals an excellent linear relationship in the lactate concentration ranging from 1.0×10−9 to 1.0×10−4 mol L−1. It has a low detection limit of 3.38×10−10 mol L−1 and high sensitivity of 4.815 mA nmol−1 L cm−2. Furthermore, the fabricated biosensor has a reasonable recovery rate for determining lactate in human serum.

Recent Advances in Electrochemical Detection of Cell Energy Metabolism

“…Commonly, the electrode surface is chemically modified using various polymers for lactate immobilization and sensitive detection. Additionally, the limit of detection (LOD) and sensitivity varies depending on the electrodes utilized [63][64][65][66].…”