Hybrid alginate-copper sulfate textile coating for coronavirus inactivation

The sanitary crisis caused by the SARS-CoV-2 has increased the demand for bioactive materials to mitigate coronavirus spread. The use of masks has been reported as an essential strategy to prevent coronavirus transmission, but they can become contaminated rapidly after use. Metals species containing compounds, especially those from the copper group, present properties that can be explored to suppress viral activity. Natural polymers, like alginate, can improve biocompatibility and adjust metal ion availability on hybrid coatings. This study assesses iron, copper, silver, and gold salts and their combination with biopolymers to design surfaces with virucidal properties. Viral inactivation assays with MHV-3 coronavirus strain and cytotoxicity tests with L929 cells were conducted to the hybrid coatings on polypropylene masks. These coatings were characterized by scanning electron microscopy with energy dispersive spectroscopy, Fourier-transform infrared spectroscopy with attenuated total reflectance device, and atomic absorption spectroscopy techniques. Multilayer coatings of alginate-copper sulfate presented 99.99% viral inactivation in a timely release of copper ions.