A polycationic antimicrobial and biocompatible hydrogel with microbe membrane suctioning ability

Abstract

Despite advanced sterilization and aseptic techniques, infections associated with medical implants have not been eradicated. Most present coatings cannot simultaneously fulfil the requirements of antibacterial and antifungal activity as well as biocompatibility and reusability. Here, we report an antimicrobial hydrogel based on dimethyldecylammonium chitosan (with high quaternization)-graft-poly(ethylene glycol) methacrylate (DMDC-Q-g-EM) and poly(ethylene glycol) diacrylate, which has excellent antimicrobial efficacy against Pseudomonas aeruginosa, Escherichia coli, Staphylococcus aureus and Fusarium solani. The proposed mechanism of the antimicrobial activity of the polycationic hydrogel is by attraction of sections of anionic microbial membrane into the internal nanopores of the hydrogel, like an 'anion sponge', leading to microbial membrane disruption and then microbe death. We have also demonstrated a thin uniform adherent coating of the hydrogel by simple ultraviolet immobilization. An animal study shows that DMDC-Q-g-EM hydrogel coating is biocompatible with rabbit conjunctiva and has no toxicity to the epithelial cells or the underlying stroma.

Canine Extremity Wound Treatment with Chitosan Extracted from Shrimp Shells: A Case Report

“…Post traumatic hemorrhage remains one of the most mortal causes of early death with progressive seconder infections in wounds. Results indicated that chitosan is a good antimicrobial barrier as reported before [9,[20][21][22][23]. The dog were stabilized and immobilized for eight weeks.…”

Combinatorial discovery of polymers resistant to bacterial attachment

“…Biofilms present on the surface of medical devices provide the bacterial inocula for disease and can also serve as reservoirs of plasmids carrying antibioticresistance genes 4,5 . Most strategies for reducing biofilm-associated infections focus on the modification of existing materials that are used to manufacture in-dwelling medical devices by the incorporation of antibiotics 6,7 or other antimicrobials, such as silver salts, nitrofurazone, chlorhexidine, polymerized quaternary ammonium surfactants, antibacterial peptides and anionic nanoporous hydrogels [8][9][10][11][12][13][14][15] . These approaches aim to kill bacterial cells that attach to a material, but we believe that greater efficacy in preventing biofilm formation might be achieved by the development of new materials that are inherently resistant to biofilm formation 16 .…”

Antimicrobial cationic polymers: from structural design to functional control

“…For instance, Chan-Park and co-workers devised an antimicrobial surface based porous polymeric hydrogels, as shown in Figure 10. 94 It is found that the porous structures of the hydrogels with abundant positive charges can adsorb anionic phospholipids from microbial membranes and disrupt them, thus killing microbes. This surface is regarded as an 'anion sponge' that exhibits broad antimicrobial activity against E. coli, Fusarium solani, S. aureus and P. aeruginosa.…”