Borneol-modified chitosan: Antimicrobial adhesion properties and application in skin flora protection.

• A new antimicrobial material, borneol-modified chitosan (BMC), was prepared. • BMC displayed good antibacterial and antifungal adhesion properties. • Guinea pig experiments were performed for skin flora evaluation. • BMC resisted pathogens but did not harm skin flora. • Stereochemical strategies are crucial for managing and controlling microbes. Antimicrobial modifications of chitosan usually endow the products with strong bactericidal activities. However, if the products come into direct contact with human skin, the skin flora, which is beneficial to human health, may be damaged. To address this issue, we developed a stereochemical antimicrobial strategy by grafting borneol 4-formylbenzoate to chitosan using a stable Schiff base bond; this process yielded borneol-modified chitosan (BMC) as a novel antimicrobial material. This material was challenged with gram-negative Escherichia coli , gram-positive Bacillus subtilis , and Aspergillus niger. All tests showed excellent antimicrobial adhesive properties. Guinea pig skin experiments further demonstrated that BMC did not damage the skin flora. Owing to the antimicrobial mechanism of borneol stereochemistry, BMC successfully defended against pathogens and protected the skin flora. Thus, this material may have excellent potential applications in multifunctional textiles, healthcare, and flexible skin electronics. [ABSTRACT FROM AUTHOR]