Multifunctional hydrogels acting as wound dressing have received extensive attention in soft tissue repair; however, it is still a challenge to develop a non-antibiotic-dependent antibacterial hydrogel that has tunable adhesion and deformation to achieve on-demand removal. Herein, an asymmetric adhesive hydrogel with near-infrared (NIR)-triggered tunable adhesion, self-deformation, and bacterial eradication is designed. The hydrogel is prepared by the crosslinking polymerization of N-isopropylacrylamide and acrylic acid, during the sedimentation of conductive PPy-PDA nanoparticles based on the polymerization of pyrrole (Py) and dopamine (DA). Due to the conversion capacity from NIR light into heat for PPy-PDA NPs, the formed temperature-sensitive hydrogel exhibits tissue adhesive as well as NIR-triggered tunable adhesion and self-deformation property, which can achieve an on-demand dressing refreshing. Systematically in vitro/in vivo antibacterial experiments indicate that the hydrogel shows excellent disinfection capability to both Gram-negative and Gram-positive bacteria. The in vivo experiments in a full-layer cutaneous wound model demonstrate that the hydrogel has a good treatment effect to promote wound healing. Overall, the asymmetric hydrogel with tunable adhesion, self-deformation, conductive, and photothermal antibacterial activity may be a promising candidate to fulfill the functions of adhesion on skin tissue, easy removing on-demand, and accelerating the wound healing process.
Hemoperfusion is an important method to remove endotoxins and save the lives of patients with sepsis. However, the current adsorbents for hemoperfusion have disadvantages of insufficient endotoxin adsorption capacity, poor blood compatibility, and so on. Herein, we proposed a novel emulsion templating (ET) method to prepare ultraporous and double-network carboxylated chitosan (CCS)-poly(diallyl dimethylammonium chloride) (PDDA) hydrogel spheres (ET-CCSPD), bearing both negative and positive charges. CCS was introduced to balance the strong positive charges of PDDA to improve hemocompatibility, and emulsion templates endowed the adsorbent with an ultraporous structure for enhanced adsorption efficacy. The ET-CCSPDs neither damaged blood cells nor activated complement responses. In addition, the activated partial thromboplastin time (APTT) was prolonged to 8.5 times, which was beneficial for reducing the injection of anticoagulant in patients. The ET-CCSPDs had excellent scavenging performance against bacteria and endotoxin, with removal ratios of 96.7% for E. coli and 99.8% for S. aureus, respectively, and the static removal ratio of endotoxin in plasma was as high as 99.1% (C 0 = 5.50 EU/mL, critical illness level). An adsorption cartridge filled with the ET-CCSPDs could remove 84.7% of endotoxin within 1 h (C 0 = 100 EU/mL in PBS). Interestingly, the ET-CCSPDs had a good inhibitory effect on the cytokines produced by endotoxin-mediated septic blood. By developing the ET method to prepare ultraporous and double-network adsorbents, the problems of low adsorption efficiency and poor blood compatibility of traditional endotoxin adsorbents have been solved, thus opening a new route to fabricate absorbents for blood purification.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.