Ó³»­´«Ã½

Timely and accurate diagnostics for infectious diseases are essential in preventing their worldwide spread. Though rapid diagnostic tests are favored for their speed, cost-effectiveness, and ease of use, most tests compromise sensitivity, which risks false-negative results. Here, we present the self-assembly of nanogold triplets on trimeric viral surface proteins for a sensitive colorimetric assay to identify viruses. Gold triplets were self-assembled on the viral trimeric surface proteins using ultrasmall gold nanoparticles. We observed a significant wavelength shift of 70 nm, enabling straightforward naked-eye detection through gold triplets that act as catalysts for producing nanoplasmonic viruses. We established the detection limit of 3 × 10 copies/ml using an effective colorimetric assay for detecting SARS-CoV-2. The self-assembly of gold triplets on trimeric viral surface proteins provides a reliable approach to the accurate and sensitive detection of viruses.