MXene/Graphene Nanoribbons Composite Materials for High-Sensitivity Enzyme-Free Electrochemiluminescent Detection of L-Lactic acid

A B S T R A C T Lactic acid level is a crucial biochemical indicator in the field of cancer diagnosis, anti-tumor therapy and other related biomedical areas. However, currently the method for detecting lactic acid is almost enzyme-based biosensors, while enzyme-free alternatives remain underexplored. In this work, we constructed a high-performance electrochemiluminescence (ECL) sensors based on Ti 3 C 2 MXene/graphene nanoribbons (MXene/GNRs) composite for the enzyme-free detection of L-lactic acid. Meanwhile, we functionalize MXene/GNRs composite with the L-lactic acid aptamer through physical and chemical interactions, and with the addition of the target L-Lactic acid, the aptamer was detached from the surface of the material, thus, the biosensor was constructed with an "on-off-on" ECL signal. The biosensor designed for this work demonstrated a detection range of L-Lactic acid from 500 nM to 10 mM, and a low detection limit of 309 nM. This work exhibits superior detection performance in complex environments, and also presents a promising enzyme-free approach for L-lactic acid monitoring in biomedical applications.