Subtle Stereochemical Structures Influence the Resistance to Protein Adsorption and Bacterial Adhesion of Polymer Surfaces as Investigated by Quartz Crystal Microbalance with Dissipation
Chiral stereochemical strategy for antimicrobial adhesion is a newly-developed strategy and is gaining growing interest. But the effect of subtle chiral stereochemical structures on the anti-biofouling property is still unclear. Herein, we designed and employed quartz crystal microbalance with dissipation (QCM-D) to comparatively study the ability of two isomers of chiral borneol compounds to inhibit proteins absorption and bacteria adhesion. Two types of polyurethanes containing endo-L-borneol-based side chains (PLBA) or exo-iso-borneol-based side chains (PIBA) were synthesized through a thiol-ene ‘click’ reaction and polyaddition polymerization. We first investigated the structure, chirality and surface wettability of the polyurethanes (PLBA-PU/PIBA-PU). Then, we in-situ investigated the protein absorption and bacteria adhesion on these polyurethane surfaces by QCMD. Results show the molecular chirality of borneol is maintained after the synthesis processes. The introduced borneol-based side chains improve the surface hydrophobicity of the polyurethanes. The PLBA-PU/PIBA-PU surfaces exhibit enhanced protein resistance and antimicrobial adhesive properties. More impressively, significant differences in anti-biofouling performance were found by QCMD between PLBA-PU and PIBA-PU with the same content of borneol-based side chains and L-configuration of borneol on the polyurethane surfaces results in better anti-biofouling function compared with exo-iso-borneol.
