Advanced fluorescence biosensor utilizing nitrogen/oxygen-doped carbon quantum dots in a modified carboxy cellulose matrix for quantitative detection of SARS-CoV-2 spike protein.

ABSTRACT: The persistent need for fast and sensitive point-of-care (POC) diagnostics for SARS-CoV-2 requires alternatives to time-consuming RT-PCR. To address this challenge, we designed and fabricated a novel fluorescence biosensor based on nitrogen/oxygen-doped carbon quantum dots embedded in an epichlorohydrin-modified carboxymethyl cellulose thin film. This robust and easily synthesized platform enabled the immobilization of spike protein-specific monoclonal antibodies, facilitating detection via fluorescence quenching and recovery at Ex/Em 320 nm/440 nm. The biosensor was characterized using Fourier-transform infrared spectroscopy, transmission electron microscopy, X-ray photoelectron spectroscopy, and fluorescence spectroscopy, confirming successful doping, nanoscale morphology, and stable opt

SUBMITTER: Alharthi S 

PROVIDER: S-EPMC12936299 | biostudies-literature | 2026 Feb

REPOSITORIES: biostudies-literature