Regenerable bacterial killing–releasing ultrathin smart hydrogel surfaces modified with zwitterionic polymer brushes

Abstract

Building long-lasting antimicrobial and clean surfaces is one of the most effective strategies to inhibit bacterial infection, but obtaining an ideal smart surface with highly efficient, controllable, and regenerative properties still encounters many challenges. Herein, we fabricate an ultrathin brush–hydrogel hybrid coating (PSBMA-P(HEAA-co-METAC)) by integrating antifouling polyzwitterionic (PSBMA) brushes and antimicrobial polycationic (P(HEAA-co-METAC)) hydrogels. The smart bacterial killing–releasing properties can be achieved independently by the opposite volume and conformation changes between the swelling (shrinking) of P(HEAA-co-METAC) hydrogel layer and the shrinking (swelling) of PSBMA brushes. The friction test reveals that both METAC and SBMA components support great lubrication. By tuning the initial organosilane (BrTMOS:KH570) ratios, the prepared PSBMA-P(HEAA-co-METAC) coating exhibits different antibacterial abilities from single “capturing–killing” to versatile “capturing–killing–releasing.” Most importantly, 99% of the bacterial-releasing rate can be easily achieved via 0.5 M NaCl treatment. This smart surface not only possesses long-lasting antibacterial performance, only ∼1.09 × 105 cell·cm−2 bacterial residue even after 72 h exposure to bacteria solutions, but also can be regenerated and triggered between water and salt solution multiple times. This work provides a new way to fabricate antibacterial smart hydrogel coatings with bacterial “killing–releasing” functions and shows great potential for biomedical applications.

Antimicrobial Hydrogels: Potential Materials for Medical Application

“…prepared hydrogels with high anti‐pollution and anti‐biofouling properties using amphiphilic‐modified graphene oxide/zinc oxide nanocomposite films. [ 214 ] Wu's group prepared ultrathin brush‐hydrogel hybrid coatings (PSBMA‐P(HEAA‐co‐Metac)) by combining antifouling polyampholytic (PSBMA) brushes with antimicrobial polycationic (P(HEAA‐co‐Metac)) hydrogels, and the prepared PSBMA‐P(HEAA‐co‐Metac) coatings exhibited different antimicrobial capabilities ranging from single “capture‐kill” to multifunctional “capture‐kill‐release.” [ 215 ] Feng et al. combined the characteristics of emulsions and hydrogels, thymus oil‐loaded amphoteric emulsion hydrogels with interconnected, homogeneous, and tunable pore structures were prepared, which have tunable mechanical properties, antifouling properties, good biocompatibility, and also inhibit the activity of Staphylococcus aureus and Escherichia coli .…”

New Hydrogels and Formulations Based on Piperonyl-Imino-Chitosan Derivatives

“…One of the most effective way to achieve that, is by using hydrogels as matrix for the encapsulation of antifungal agents. Hydrogels are materials used at large scale for a wide range of applications, such as actuators [ 6 ], waste water treatment [ 7 ], long-lasting antimicrobial materials [ 8 ] and drug delivery systems [ 9 ], due to their versatile properties. Among the polymers used for hydrogels’ preparation, chitosan (C), which is a polysaccharide derived from chitin [ 10 ], is intensely used due to its intrinsic properties: biocompatibility, biodegradability and very important similarity with the extracellular matrix from compositionally and mechanical properties points of view [ 11 , 12 , 13 ].…”

An Anisotropic Hydrogel by Programmable Ionic Crosslinking for Sequential Two-Stage Actuation under Single Stimulus

“…How to improve the intelligence degree of materials is one of the core issues in this field. Stimuli-responsive hydrogels [ 3 , 4 , 5 ], as a class of elastomers, have attracted more and more attention due to their great biocompatibility, soft-wet, and structural/composition designability. Many efforts have demonstrated their great potential in soft robots [ 6 ], biosensors [ 7 , 8 ], drug delivery [ 9 ], and so on [ 10 ].…”