Nb<sub>4</sub>C<sub>3</sub>T<sub>x</sub> (MXene)/Au/DNA Aptasensor for the Ultraselective Electrochemical Detection of Lead in Water Samples
P. Abdul Rasheed, Ravi P. Pandey, Khadeeja Abdul Jabbar, Khaled A. Mahmoud
Abstract
Abstract An electrochemical aptasensor was designed for the ultraselective and sensitive detection of Pb 2+ by using lead‐specific binding DNA oligonucleotide as the molecular recognition element on Au nanoparticles/Nb 4 C 3 T x MXene (Au@Nb 4 C 3 T x ) modified electrode. The Au@Nb 4 C 3 T x is conjugated with thiol‐modified lead‐binding DNA through the Au−S bond. The DNA−Au@Nb 4 C 3 T x modified glassy carbon electrode exhibited ultrahigh selectivity and enhanced response towards the detection of Pb 2+ with a detection limit of 4 nM and linear range of 10 nM to 5 μM. This work has proved the possibility of using Nb 4 C 3 T x as a robust immobilization platform for DNA oligonucleotides towards different environmental sensing and biomedical applications.