Engineering Rechargeable Antibacterial Coatings on Stainless Steel for Efficient Inactivation of Pathogenic Bacteria in the Presence of Organic Matter

Worldwide, around 600 million people are affected by foodborne illnesses each year which highlights the importance of food safety. It is important to ensure the cleanliness of the working surfaces in food processing facilities. Stainless steel is widely used in the food industry as a food contact surface. Endowing stainless steel with a potent rechargeable antibacterial function offers the prospect of a reusable and clean surface. In this study, a “clickable” coating for stainless steel was developed. Quaternized azido-hydantoin (C1), quaternary ammonium compound (C2) and azido-hydantoin (C3) were bonded to stainless steel primed with the “clickable” coating to yield three samples: SSMC1, SSMC2 and SSMC3, respectively. The coating was stable during the chlorination process which was used to convert the immobilized C1 and C3 to their N-chloramine counterparts (SSMC1-Cl and SSMC3-Cl respectively). It was shown that SSMC1-Cl had the best antibacterial activity, with 100% reduction of E. coli and S. aureus af...