The study investigates the development of surfaces that can kill bacteria on contact, focusing on poly(4-vinyl-N-alkylpyridinium bromide) (PVP) covalently attached to glass slides. The antibacterial properties were assessed by spraying bacterial suspensions onto the surfaces and counting the viable cells after air drying. Different alkyl groups (from propyl to hexadecyl) were used to modify the PVP chains, with hexyl-PVP showing the highest effectiveness, reducing viable S. aureus cells by 94 ± 4%. The same method was tested on other Gram-positive and Gram-negative bacteria, showing a more than 100-fold reduction in viable cells. The antibacterial activity was maintained even after drying, and the surfaces were found to be effective against common materials like ceramics, plastics, metals, and wood. The study suggests that this approach could be useful for coating consumer and medical products to make them antibacterial.The study investigates the development of surfaces that can kill bacteria on contact, focusing on poly(4-vinyl-N-alkylpyridinium bromide) (PVP) covalently attached to glass slides. The antibacterial properties were assessed by spraying bacterial suspensions onto the surfaces and counting the viable cells after air drying. Different alkyl groups (from propyl to hexadecyl) were used to modify the PVP chains, with hexyl-PVP showing the highest effectiveness, reducing viable S. aureus cells by 94 ± 4%. The same method was tested on other Gram-positive and Gram-negative bacteria, showing a more than 100-fold reduction in viable cells. The antibacterial activity was maintained even after drying, and the surfaces were found to be effective against common materials like ceramics, plastics, metals, and wood. The study suggests that this approach could be useful for coating consumer and medical products to make them antibacterial.