Surface Modification of Silicone for Biomedical Applications Requiring Long-Term Antibacterial, Antifouling, and Hemocompatible Properties

Abstract

Silicone has been used for peritoneal dialysis (PD) catheters for several decades. However, bacteria, platelets, proteins, and other biomolecules tend to adhere to its hydrophobic surface, which may lead to PD outflow failure, serious infection, or even death. In this work, a cross-linked poly(poly(ethylene glycol) dimethacrylate) (P(PEGDMA)) polymer layer was covalently grafted on medical-grade silicone surface to improve its antibacterial and antifouling properties. The P(PEGDMA)-grafted silicone (Silicone-g-P(PEGDMA)) substrate reduced the adhesion of Staphylococcus aureus , Escherichia coli , and Staphylococcus epidermidis , as well as 3T3 fibroblast cells by ≥90%. The antibacterial and antifouling properties were preserved after the modified substrate was aged for 30 days in phosphate buffer saline. Further immobilization of a polysulfobetaine polymer, poly((2-(methacryloyloxy)ethyl)dimethyl-(3-sulfopropyl)ammonium hydroxide) (P(DMAPS)), on the Silicone-g-P(PEGDMA) substrate via thiol-ene click reaction leads to enhanced antifouling efficacy and improved hemocompatibility with the preservation of the antibacterial property. Compared to pristine silicone, the so-obtained Silicone-g-P(PEGDMA)-P(DMAPS) substrate reduced the absorption of bovine serum albumin and bovine plasma fibrinogen by ≥80%. It also reduced the number of adherent platelets by ≥90% and significantly prolonged plasma recalcification time. The results indicate that surface grafting with P(PEGDMA) and P(DMAPS) can be potentially useful for the modification of silicone-based PD catheters for long-term applications.

Fabrication of nonfouling, bactericidal, and bacteria corpse release multifunctional surface through surface-initiated RAFT polymerization

“…31 However, the highly hydrophobic nature often leads to the adhesion of bacteria, proteins, and biomolecules on the silicone surface. So, it is imperative to modify PDMS surface into hydrophilic surface to enhance its anti-adhesion function.…”

Structures and Synthesis of Zwitterionic Polymers

“…RDRP methods enable also the anchoring of polyzwitterions to surfaces by "grafting-through" [105] and "grafting-to" processes [193,203,[313][314][315][316][317]. In particular, the latter profits from the facile incorporation of reactive groups in special positions, e.g., in the center or at the ends of the polymers, that enable efficient attachment of the macromolecules onto the substrates.…”

“…In particular, the latter profits from the facile incorporation of reactive groups in special positions, e.g., in the center or at the ends of the polymers, that enable efficient attachment of the macromolecules onto the substrates. Still, classical grafting-from [318][319][320][321][322][323][324][325][326][327][328][329][330][331][332][333][334][335], grafting-to [336][337][338][339][340][341][342][343][344][345][346], and grafting-through [316,347] procedures are of course continuously in use, especially in industrial applications, where the activation of the surfaces for the grafting process by physical means or by simple, "unpretentious" chemistry is preferred for reasons of experience, cost and high-throughput.…”

Synthesis of PEGylated chitosan copolymers as efficiently antimicrobial coatings for leather

“…Actually, effective hydration of the coating is critical for non-fouling properties, avoiding the adhesion of microorganisms. 26,27 Therefore, such PEG-g-CS coating was supposed to be effective in preventing microorganisms' adsorption.…”