Tunable aptamer-MXene sensing interface for label-free and real-time detection of toxic pollutants in water samples

Jinghua Liu; Feng Tan; Tianhao Cao; Runqiang Yu; Yan Wang

doi:10.1016/j.bios.2024.117096

Tunable aptamer-MXene sensing interface for label-free and real-time detection of toxic pollutants in water samples

Biosens Bioelectron. 2024 Dec 23:271:117096. doi: 10.1016/j.bios.2024.117096. Online ahead of print.

Authors

Jinghua Liu¹, Feng Tan², Tianhao Cao¹, Runqiang Yu³, Yan Wang¹

Affiliations

¹ Key Laboratory of Industrial Ecology and Environmental Engineering (MOE), School of Environmental Science and Technology, Dalian University of Technology, Dalian, 116024, China.
² Key Laboratory of Industrial Ecology and Environmental Engineering (MOE), School of Environmental Science and Technology, Dalian University of Technology, Dalian, 116024, China. Electronic address: tanf@dlut.edu.cn.
³ School of Chemistry and Chemical Engineering, Liaoning Normal University, Dalian, 116029, China.

PMID: 39731820
DOI: 10.1016/j.bios.2024.117096

Abstract

Stable and low-cost field-effect transistor (FET)-based biosensors are vital for the on-site detection of toxic pollutants in environmental monitoring applications. In this study, a tunable aptamer-MXene sensing interface was constructed to develop renewable FET biosensors. This was achieved through the reversible disulfide bond (-S-S-) reaction between the SH-Ti₃C₂T_x film and thiolated aptamer. Ti₃C₂T_x film was prepared using layer-by-layer assembly of Ti₃C₂T_x flakes and used as the conductance channel of this FET device. Then, dithiothreitol modification was carried out through the formation of Ti-S bonds. The reversible -S-S- bonds enabled the repeated regeneration of SH-Ti₃C₂T_x, which allowed deferent aptamers to be immobilized. Therefore, multiple targets could be detected with the same FET device, avoiding device-to-device variations. Three specific aptamers for microcystin-LR, β-lactam-resistant gene (β-ARG), and Hg²⁺ were adopted to demonstrate this characteristic. The prepared aptamer-MXene FET biosensor showed high sensitivity, repeatability and stability. Furthermore, a strong real-time response was observed upon exposure to the targets. This study demonstrated that constructing a tunable aptamer-MXene sensing interface is an efficient strategy for constructing cheap and renewable aptamer-MXene FET biosensors for the label-free and real-time detection of toxic pollutants.

Keywords: Biosensor; Environmental monitoring; Field-effect transistor; Ti(3)C(2)T(x); Tunable sensing interface.