Nb4C3Tx (MXene)/Au/DNA Aptasensor for the Ultraselective Electrochemical Detection of Lead in Water Samples

An electrochemical aptasensor was designed for the ultraselective and sensitive detection of Pb2+ by using lead-specific binding DNA oligonucleotide as the molecular recognition element on Au nanoparticles/Nb4C3Tx MXene (Au@Nb4C3Tx) modified electrode. The Au@Nb4C3Tx is conjugated with thiol-modified lead-binding DNA through the Au-S bond. The DNA-Au@Nb4C3Tx modified glassy carbon electrode exhibited ultrahigh selectivity and enhanced response towards the detection of Pb2+ with a detection limit of 4 nM and linear range of 10 nM to 5 mu M. This work has proved the possibility of using Nb4C3Tx as a robust immobilization platform for DNA oligonucleotides towards different environmental sensing and biomedical applications.

Automated summary

An electrochemical aptasensor based on DNA oligonucleotide was developed for the selective and sensitive detection of Pb2+. The Au@Nb4C3Tx modified electrode showed high selectivity and enhanced response towards Pb2+ detection, with a detection limit of 4 nM and a linear range of 10 nM to 5 μM. This study demonstrated the potential of using Nb4C3Tx as a stable immobilization platform for DNA oligonucleotides in environmental sensing and biomedical applications.