Solvent-Free Graft-From Polymerization of Polyvinylpyrrolidone Imparting Ultralow Bacterial Fouling and Improved Biocompatibility

Abstract

Polymer grafting has been a powerful tool in the surface modification of biomaterials. Traditional solventbased grafting, however, often requires laborious procedures taken under harsh conditions, which seriously hinders its practical applications. Here, we report a facile solvent-free graft-from method that is able to achieve a superior surface functionality as compared to most reported results from traditional solvent-based grafting. The grafting was proceeded by conformally coating a cross-linked polyvinylpyrrolidone (PVP) prime layer in the vacuum, immediately followed by in situ grafting of PVP homopolymer chains from the propagating sites on the coating surface. The resultant coating exhibited enriched surface pyrrolidone content compared to the single-layer cross-linked counterpart and a water contact angle of 22°, lower than most reported PVP-grafted surfaces. Medical catheters grafted with PVP achieved a more than 99.9% bacterial antifouling enhancement compared to the pristine catheter, and significantly improved biocompatibility during a 4 week in vivo test in mice. The achieved surface functionality is attributed to the synergistic effect from the functional groups distributed both on the grafted chains and on the cross-linked primer. The effectiveness and simplicity of the vapor grafting method thus suggest a promising surface modification route for biomaterials and beyond.

Multipronged Approach to Combat Catheter-Associated Infections and Thrombosis by Combining Nitric Oxide and a Polyzwitterion: a 7 Day In Vivo Study in a Rabbit Model

“…Additionally, according to the Centers for Disease Control and Prevention, 30,100 CLABSI cases are reported every year in the intensive care units and acute care facilities of the US . As such, the development of a thromboresistant and antimicrobial catheter-coating material is of utmost importance. − However, another consideration for the development of a catheter-coating material is to design a material that would form a “biocompatible system” when placed in the major vein. − The term biocompatible has been defined as “the ability of a material to perform with an appropriate host response in a specific situation” . To explain in simpler terms, this means that a material is considered biocompatible if it does not elicit any adverse reactions in the living system.…”

Solvent-Free Fabrication of Self-Regenerating Antibacterial Surfaces Resisting Biofilm Formation

“…Similarly, with the increase of EGDA and decrease of the MAH content, the intensity of the absorption band at 1735 cm –1 gradually increased, while the intensity of peaks at 1802 and 1737 cm –1 gradually decreased. The content ratios of these copolymers were calculated following a previously reported method, and the detailed procedures are listed in the Supporting Information. , …”

The Mechanisms and the Applications of Antibacterial Polymers in Surface Modification on Medical Devices

“…Our group has investigated a novel antimicrobial coating technology, in which the silicon substrate was modified by a cross-linked polyvinylpyrrolidone (PVP) under vacuum, immediately followed by in situ grafting of PVP homopolymers using solvent-free graft-from polymerization method. A total of 99.9% antifouling enhancement was achieved after the catheter was modified while the improved biocompatibility was also observed in a 4-week in vivo tests in mice because of good hydrophilicity of PVP ( Sun et al, 2019 ). Dimethylaminomethylstyrene (DMAMS) or poly (dimethylaminomethylstyrene-co-ethylene glycol diacrylate) [P(DMAMS-co-EGDA)] at different crosslinking ratios was once vaporously deposited on flat and porous substrates, using tert-butyl peroxide (TBP) as an initiator and ethylene glycol diacrylate (EGDA) as a cross-linking agent.…”