Metal organic framework derived tubular-like indium trioxide to construct photoelectrochemical sensor for detecting carcinoembryonic antigen

Photoelectrochemical (PEC) sensor realizes high sensitivity detection of biomolecules and chemical substances through the combination of photoelectric conversion and chemical reaction, which has important significance in biomedicine and environmental monitoring. In this work, we designed a flexible PEC sensor based on In2O3-CdS hierarchical heterojunction for detecting carcinoembryonic antigen (CEA) in human serum. In2O3-CdS hierarchical heterojunction exhibited outstanding photoelectrochemical performance, which lays the foundation for a highly sensitive detection process. The electron transfer process was impeded as a result of the antigen being recognized and captured by the specific antibody on the electrode surface, leading to the decline of the photocurrent signal. Based on this principle, the PEC sensor exhibited a good linear relationship range from 0.002 ng mL−1 to 20 ng mL−1 under the most suitable conditions. In addition, this PEC sensor showed better stability and reproducibility in real samples compared to the commercially available ELISA kit. This work provided a reliable method for early cancer screening and diagnosis, which exhibited great significance and broad prospect for improving cancer treatment effect and survival rate.