Two-dimensional Ti2C MXene-induced photocurrent polarity switching photoelectrochemical biosensing platform for ultrasensitive and selective detection of soluble CD146

• Published in: Sensors and actuators. B, Chemical Chemical, 2022-01, Vol.350, p.130859, Article 130859
• Main Authors: Jiang, Guihua, Yang, Ruiying, Liu, Jie, Liu, Huimin, Liu, Li’e, Wu, Yongjun, A., Youmei
• Format: Article
• Language: English
• Subjects: Ag2S quantum dots; Antibodies; Antigens; Biosensors; Indium tin oxides; MXenes; Photocathodes; Photocurrent polarity switching; Photoelectric effect; Photoelectric emission; Photoelectricity; Photoelectrochemical biosensor; Quantum dots; Soluble CD146; Switching (polarity); Two dimensional materials; Two-dimensional Ti2C MXene
• ISSN: 0925-4005; 1873-3077
• DOI: 10.1016/j.snb.2021.130859

Two-dimensional (2D) materials with unique structures and fascinating photoelectric properties are typically employed as supporting materials but they have not been mentioned in the context of polarity-reversal-mode photoelectrochemical (PEC) biosensors. Herein, a novel 2D Ti2C MXene-induced photocurrent polarity switching PEC biosensing platform was constructed for the selective and ultrasensitive detection of soluble CD146 (sCD146). Ag2S quantum dots (QDs)-fixed indium-tin oxide slices were used as the photocathode electrodes, and the capture antibody (Ab1) was assembled on the electrode. When the target sCD146 existed, 2D Ti2C MXene labeled with the detection antibody (Ab2) was introduced onto the modified electrode through a typical antigen-antibody sandwich immune reaction, resulting in a polarity switch from a cathodic to an anodic photocurrent. The outstanding optical and electron-transfer capability of the 2D Ti2C MXene made it beneficial to establish a high-performance photocurrent polarity switching PEC biosensor for sCD146 assay, and a linear response range of 0.1–1000 pg/mL with a detection limit of 18 fg/mL was obtained. Furthermore, the developed PEC biosensing strategy possessed excellent anti-interference ability for precluding the false positive or negative signals. The designed 2D Ti2C MXene opens up a new two-dimensional photocurrent-polarity switcher for constructing high-performance PEC biosensors, and the environmentally friendly 2D Ti2C MXene//Ag2S QDs photocurrent polarity switching system could overcome the harmfulness of conventional toxic semiconductors for operators and the environment, offering great potential applications in biological analysis and disease diagnosis. •2D Ti2C MXene with unique properties was applied as a novel dimensional photocurrent-polarity switcher.•An ultrasensitive and selective photoelectrochemical biosensing platform was developed for the detection of soluble CD146.•The environmentally friendly 2D Ti2C MXene//Ag2S QDs photocurrent polarity switching system could overcome some harmfulness.