Photoelectrochemical biosensor based on ReS2@modified carbon nitride for highly sensitive detection of MicroRNA-155

Early cancer diagnosis is critically enhanced by detecting microRNA (miRNA) biomarkers, such as miRNA-155, whose overexpression correlates with cancer progression. This work presents a highly sensitive photoelectrochemical (PEC) biosensor for miRNA-155 detection leveraging a modified carbon nitride (m-CN) substrate modified by ReS₂ (ReS₂/m-CN), which enhanced electron transfer efficiency and provided abundant sites. The resulting biosensor exhibits exceptional performance with a broad linear detection range from 10 −16  M to 10 −7  M, an ultralow detection limit, high selectivity, and outstanding stability. This work demonstrates the significant potential of the ReS 2 @m-CN-based PEC biosensor for sensitive, cost-effective early cancer diagnostics.