Polylactic acid film surface functionalized by zwitterionic poly [2-(methacryloyloxy)ethyl choline phosphate] with improved biocompatibility

Polylactic acid (PLA) is a non-toxic, biodegradable biological material that is widely used in tissue engineering and regenerative medicine. PLA is easy to adsorb non-specific proteins and lacks cell adhesion after implantation. Choline phosphate (CP) is a novel zwitterion with a reverse structure of phosphate choline (PC) on the cell membrane that can form a specific CP-PC interaction to promote cell adhesion. In our previous work, modi-fication of choline phosphate polymers (PMCP) onto the PLA film surface improved the hydrophilicity and degradation properties. In this study, we further investigated the biocompatibility of PLA-PMCP films from protein adsorption, cell adhesion and proliferation, bacterial adhesion, blood compatibility, and inflammation in vivo. The PLA-PMCP surface can resist protein adsorption and bacterial adhesion due to the anti-fouling prop-erties of the zwitterion PMCP. Meanwhile, the PLA-PMCP surface promotes the adhesion and proliferation of BMSCs due to the specific CP-PC effect. In addition, the PLA-PMCP film has good blood compatibility as well as the PLA film. During in vivo experiments, biocompatibility was improved and the inflammatory response and immune rejection of PLA-PMCP films were reduced compared to those of the original PLA film. Therefore, the PMCP-modified PLA film resists protein adsorption and bacterial adhesion, promotes cell adhesion and prolif-eration, and has good hemocompatibility and histocompatibility. This brings a significant potential for appli-cation in the fields of tissue engineering and regenerative medicine.

Automated summary

This study investigated the biocompatibility of PLA-PMCP films in terms of protein adsorption, cell adhesion and proliferation, bacterial adhesion, blood compatibility, and inflammation in vivo. The results showed that the PLA-PMCP surface can resist protein adsorption and bacterial adhesion, promote cell adhesion and proliferation, and have good hemocompatibility and histocompatibility.