Advanced Non-Invasive Nanobiosensors for Point-of-Care Diagnostics: Nanomaterial-Based Detection in Saliva

Abstract

     Saliva, as a non-invasive biofluid containing a wide range of biological markers, offers unique opportunities for rapid and non-invasive disease detection. Despite its complex composition and presence of impurities, the development of nanobiosensors based on graphene, gold nanoparticles, quantum dots, magnetic nanoparticles, and two-dimensional nanomaterials has enabled sensitive and rapid detection in saliva samples. These sensors include electrochemical, voltammetric, impedimetric, SPR, and field-effect transistor (FET)-based platforms, with potential integration into portable devices and nanochips. The use of aptamers, nanobodies, and peptide-based bioprobes enhances diagnostic performance.

    Various nanomaterial synthesis and surface modification strategies, Cas12a-based sensors, and lateral flow (LFA) and ELISA assays were applied for the detection of proteins, viruses, and miRNAs in saliva. Results demonstrated that the developed sensors can detect targets such as SARS-CoV-2 within 20 minutes. Nanobiosensors pave the way for smart devices and personalized clinical applications, providing high potential for non-invasive detection of bacterial, viral, cancer, and cardiovascular biomarkers.