Polyelectrolyte film based on pectin and poly(diallyldimethylammonium chloride) with antioxidant and antimicrobial activity

This study aimed to develop an antimicrobial polyelectrolyte film using pectin and poly(diallyldimethylammonium chloride) (PDADMAC), focusing on the inactivation of the coronavirus. The film demonstrated remarkable effectiveness, eliminating 99% of the MHV-3 coronavirus in just 1 min of direct contact. In addition, it showed a solid ability to combat Staphylococcus aureus and Escherichia coli bacteria. The incorporation of PDADMAC into the pectin matrix had a significant impact (p < 0.05) on several physicochemical properties of the films compared to the control film (without PDADMAC). The films exhibited an average increase of 93.6% in tensile strength and 53% in water vapor permeability. PDADMAC also influenced the thermal stability of the films, and SEM micrographs revealed compact and homogeneous surfaces. In addition, the antimicrobial film showed the ability to eliminate 9.6% of DPPH free radicals, suggesting its potential use as an antioxidant. These results highlight the promising application of PDADMAC in producing pectin-based polyelectrolyte films with functional properties, including a marked antimicrobial activity against the coronavirus and bacteria.