Search

Chitosan exhibits remarkable broad-spectrum antibacterial activity, especially in acidic environments. However, its poor solubility in water and significantly decreased antibacterial performance after membrane formation greatly limit its extensive application. To address this issue, glycol chitosan-4-pyridylcarboxaldehydeborneol (GCBP) was synthesized by conjugating glycol chitosan (GC) with 4-pyridylcarboxaldehydeborneol ester (BP) through dynamic Schiff base bonds utilizing a layer-by-layer self-assembly strategy. When bacteria come into contact with the surface, the local acidic microenvironment triggers the cleavage of the Schiff base, resulting in the release of bactericidal BP and GC for combined sterilization. In vitro results demonstrated that the antibacterial properties of GCBP were positively related to the modification layers. The excellent antibacterial performance of the GCBP modification demonstrates not only great potential for clinical urinary catheters but also for broad antibacterial applications in the medical field. [ABSTRACT FROM AUTHOR]

Polyester is widely used in biomedical, textile, and food packaging fields. Therefore, enhancing it with antimicrobial properties would be a significant advancement. In this paper, a series of borneol-triazine polyesters (BTPs) with different structures are synthesized through room temperature polycondensation. The structure and composition of BTPs are systematically characterized by 1H NMR, FTIR and GPC. Antimicrobial results reveal that the ability of BTPs to resist bacterial or fungal adhesion is directly related to the polymer structure. When the polymer chain of BTPs adopts a rigid structure, they exhibit excellent anti-adhesive and inhibitory performances against both Gram-negative bacteria (Escherichia coli) and Gram-positive bacteria (Staphylococcus aureus). Meanwhile, the as-synthesized BTPs poses a fungal-repelling effect on common fungal strains (Aspergillus niger) for up to 30 d. Further studies have shown that a stereochemical structure brought by borneol is key for imparting effective antimicrobial properties to BTPs. In addition, BTPs are non-leaching materials with low cellular cytotoxicity. Taking into consideration, BTP provides a potential strategy for preparing a new class of antimicrobial polyester materials. [Display omitted] • BTPs, as a series of new type of antimicrobial polyesters, are synthesized. • BTPs can inhibit the spread of microorganisms, including bacteria and fungi. • BTPs achieves antimicrobial adhesion by stereochemistry strategy. • The rigidity of BTPs have a significant impact on antimicrobial adhesion. • BTPs are non-leaching antimicrobial polymers. [ABSTRACT FROM AUTHOR]

• 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]