Lab-made sugar-coated particle reduces COVID-19 infection rates by 98.6% in human cell tests

Research led by a Swansea University academic has revealed a synthetic glycosystem – a sugar-coated polymer nanoparticle – that can block COVID-19 from infecting human cells, reducing infection rates by nearly 99%.

The glycosystem is a specially designed particle that mimics natural sugars found on human cells. These sugars, known as polysialosides, are made of repeating units of sialic acid – structures that viruses often target to begin infection.

By copying this structure, the synthetic molecule acts as a decoy, binding to the virus's spike protein and preventing it from attaching to real cells.

Unlike vaccines, which trigger immune responses, this molecule acts as a physical shield, offering a novel approach to infection prevention.

Tests on human lung cells showed a 98.6% reduction in infection when the molecule was present. Crucially, the research highlighted that its effectiveness stems not just from its charge, but from its precise sugar structure – giving this glycosystem its powerful infection-blocking capability.

Image source: Khatri et al. (2025), Small.