Potential screening of oral squamous cell carcinoma using microRNA geno-assay by electrochemical sensing: a new platform in biosensor technology.

Early-stage diagnosis of oral squamous cell carcinoma (OSCC), a prominent global cause of mortality, is crucial for minimizing morbidity and mortality rates. MicroRNA-423-5p is chosen for effective identification of OSCC because of its high specificity in the Receiver Operating Characteristic (ROC) curve, enabling precise diagnosis of oral cancer (OC) in human biofluids. This work introduces a novel label-free electrochemical platform for the non-invasive recognition of microRNA-423-5p in human saliva samples. The monitoring is achieved by a DNA-based bioassay. In order to achieve this objective, polychitosan (P(CS)) was electropolymerized on the surface of a glassy carbon electrode (GCE) and used as a high-potential capturing layer on the surface of the GCE. Also, triangular silver nanoparticles (TA-AgNPs) were used for stable immobilization of probe-DNA. This allowed for the effective immobilization of thiolated DNA sequences via the interaction with TA-AgNPs. This immobilization was achieved utilizing a DNA-microRNA-423-5p hybridization approach. Therefore, a label-free genosensor was prepared for the sensitive recognition of OC. Using the electroanalysis method, microRNA-423-5p was determined in human saliva samples in the linear range of 1pM to 5 nM with a low limit of quantification of 1 pM. Because this report is the first application of electroanalysis strategy to the recognition of OC biomarker (microRNA-423-5p), therefore, a new horizon opens for cancer diagnosis.