Atomic-Level Defect\nEngineering in GeP Nanoflake Biosensors\nfor Gastric Cancer Diagnosis

Defect engineering offers a promising approach to enhance\nthe sensitivity\nof biosensing materials by creating abundant chemically active sites.\nDespite its potential, achieving precise control and modification\nof these defects remains a significant challenge. Herein, we propose\natomic-level defect engineering in GeP two-dimensional (2D) layered\nmaterials, following precise <i>in situ</i> growing Au nanoparticles\non the single defect active sites for the design of ultrasensitive\nbiosensors. The GeP-based biosensor exhibits notable capabilities\nfor miRNA detection with excellent chemical stability, sensitivity,\nselectivity, and an extremely low detection limit of 28.6 aM. When\napplied to clinical tissue samples from gastric cancer patients, the\nbiosensor effectively quantified the miR378c biomarker, enabling accurate\nstage-specific monitoring. This research not only represents a crucial\nadvancement in the field of biosensing materials through defect engineering\nbut also provides a promising avenue for early cancer diagnosis, staging,\nand monitoring.