Competitive displacement induced photoelectrochemical aptasensor based on MXene/TiO2 heterojunction for highly sensitive detection of Golgi protein 73

Fusiform TiO 2 nanoparticles is in-situ grew on the surface of HCl etching MXene. • MXene/TiO 2 heterojunction is served as the outstanding photoactive material in PEC platform. • This PEC aptasensor adopts the competitive displacement for sensitive and specific quantification of GP73. • The constructed PEC aptasensor is successfully applied to directly monitor GP73 in human serum samples. Golgi protein 73 (GP73) is a promising serological biomarker for the early diagnosis and prognosis of hepatocellular carcinoma (HCC), it is essential to develop a sensitive detection method for GP73. Benefiting from its high sp 2 graphitic degree, efficient photoinduced electron–hole transfer, and robust transport of photogenerated ion migration abilities, the MXene/TiO 2 heterojunction was employed to fabricate a competitive photoelectrochemical (PEC) aptasensor for sensitive GP73 detection. In this study, GP73 possessed higher affinity with GP73 Apt than cDNA, and competitively displaced cDNA from GP73 Apt upon the binding process. This MXene-based PEC aptasensor displayed a logarithmic linear response to GP73 in the concentration range of 7.3–3650 ng/mL with a limit of detection (LOD) of 0.42 ng/mL. Remarkably, this strategy was enabled to directly determinate GP73 in human serum samples of health control, esophageal cancer, gastric cancer, and HCC with analytical performance comparable to ELISA. Therefore, the proposed PEC sensing system may hold promising prospects for clinical detection of gastrointestinal cancers biomarker. The fabricated competitive displacement-triggered PEC aptasensor based on MXene/TiO 2 heterojunction is employed to directly determinate GP73 in human serum samples of hepatocellular carcinoma. Download: Download high-res image (115KB) Download: Download full-size image