Single-Molecule Evaluation of the SARS-CoV-2 Nucleocapsid Protein Using Gold Particle-in-a-Frame Nanostructures Enhanced Fluorescent Assay.
Jiale ZhuXuan ZhaoJinpeng MaoNa NaJin OuyangPublished in: Analytical chemistry (2023)
Ultrasensitive evaluation of low-abundance analytes, particularly with limits approaching a single molecule, is a key challenge in the design of an assay for profiling severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) antigen. Herein, we report an aptamer claw strategy for directly evaluating the SARS-CoV-2 antigen based on gold particle-in-a-frame nanostructures (Au PIAFs). Au PIAF was used as a metal-enhanced fluorescence material. The assay integrated with a microplate reader achieved a sensitivity of 44 fg·mL -1 in under 3 min and accurately detected the SARS-CoV-2 nucleocapsid protein (N protein) in human saliva samples. When our assay is combined with a single-molecule counting platform, the limit of detection can be as low as 0.84 ag·mL -1 . This rapid and ultrasensitive assay holds promise as a tool for screening SARS-CoV-2 and other contagious viruses.
Keyphrases
- single molecule
- sars cov
- respiratory syndrome coronavirus
- high throughput
- living cells
- atomic force microscopy
- quantum dots
- label free
- gold nanoparticles
- sensitive detection
- coronavirus disease
- endothelial cells
- protein protein
- loop mediated isothermal amplification
- reduced graphene oxide
- machine learning
- binding protein
- small molecule
- deep learning
- mass spectrometry
- artificial intelligence
- wastewater treatment
- microbial community
- highly efficient
- visible light
- fluorescent probe