Tailoring MXene-Heterometal-Doped MOF Composites via One-Step Room-Temperature Synthesis for Enhanced Electrochemical Detection of <scp>L</scp>-Tryptophan
Li Zhang, Minjie Liang, Chao Li, Fengbo Li, Jianjiao Xin, Jiaxin Lang, Shaobin Li, Deqing Zhang
Abstract
L -Tryptophan ( l -Trp) is an essential amino acid that is critical to human health and biosynthetic processes. Hence, developing a simple and sensitive l -Trp sensor is of great importance. In this study, a Ce-doped MOF-199/Ti 3 C 2 T X MXene nanocomposite was developed to detect l -Trp. Density functional theory (DFT) calculation suggested that the doping of Ce can effectively enhance the electronic structure of MOF-199 and improve its adsorption capacity for l -Trp. Additionally, the integration of Ce-doped MOF-199 with Ti 3 C 2 T X MXene substantially improves the conductivity of MOFs, resulting in enhanced electrocatalytic activity of the nanocomposite material. The sensor exhibits a wide linear range (0.5–156.5 μM), low limit of detection (0.18 μM), and excellent selectivity. Further, the sensor possesses excellent reproducibility, repeatability, and long-term stability. It has been successfully used to detect l -Trp in milk with excellent recoveries (99.66–104.40%).