Dual‐Light‐Triggered In Situ Structure and Function Regulation of Injectable Hydrogels for High‐Efficient Anti‐Infective Wound Therapy

Abstract

Most injectable hydrogels used in biomedical engineering have unsatisfactory and untunable mechanical properties, making it difficult to match them with the mechanical strengths of different tissues and organs, which can cause a series of adverse consequences such as immune rejection and soft tissue contusion. In this contribution, dopamine-modified hyaluronic acid (HA-DA) is developed as the backbone for an injectable hydrogel using a catechol-Fe 3+ coordination crosslinking strategy. Due to dynamic physical crosslinking, the hydrogel can be easily injected through a single syringe. Into the hydrogel, black phosphorous nanosheets loaded with a Zr-based porphyrinic metal−organic framework (PCN@BP) are introduced that could generate reactive oxygen species (ROS) under 660 nm laser irradiation, this promotes the oxidative coupling of dopamine in the presence of the ROS, introducing in situ chemical crosslinking into the hydrogel. A physical/chemical double-crosslinked hydrogel is obtained, effectively improving the hydrogel's mechanical properties, which are tuned in situ by adjusting the irradiation time to match the mechanical modulus of different biological tissues. Combining the excellent photothermal properties and photodynamic performance of the PCN@BP nanosheets yields effective sterilization under mild conditions (below 50 °C, low ROS production). The results show that this hydrogel is an excellent multifunctional wound dressing.

Recent advances in engineered polymeric materials for efficient photodynamic inactivation of bacterial pathogens

“…Addition of Zr-based porphyrinic MOF-loaded BP nanosheets could generate ROS under 660 nm laser irradiation, which promoted the oxidative coupling of dopamine to form the chemical crosslinker within the hydrogel matrix. The as-obtained injectable hydrogel exhibited good APDT and APTT effects for effective sterilization [ 154 ]. Recently, a self-healing hydrogel consisting of PEG diamine, oxidized dextran (ODex), and amine-terminated PEG-functionalized CuS NPs was developed via Schiff base reactions.…”

Advances in modified hyaluronic acid-based hydrogels for skin wound healing

“…[167][168][169][170][171]251 Through careful selection of monomers and crosslinking agents, the hydrophilicity and porosity of the hydrogel was found to have an excellent effect in antibacterial applications. 172 HA-based hydrogels with antibacterial activity can be roughly divided into the following types according to the different antibacterial components: inorganic nanoparticles with antibacterial function (such as Ag nanoparticles, 173,174 ZnO 175 ), loading with antibiotic drugs, for example, antibiotic (gentamicin, 176 ampicillin 177 ), antimicrobial peptides (SWLSKTAKKLFKKIPKKIPKKRFPRPRPWPRPNMI-NH2, 178 KK (SLKL)3KK 179 ), antibacterial compounds (curcumin, 100 chlorhexidine diacetate, 153 polyarginine 180 ), materials capable of generating reactive oxygen species with bactericidal ability (Ag ions, 181 Zr-based porphyrinic metal−organic framework, 182 silver nanoparticles 183 ), and hydrogels that possess antibacterial ability (bionic hydrogels obtained via dual-crosslinking between oxidized HA (HA-CHO) and dopa-grafted ε-polylysine, 184 a hydrogel with thiol derivatised HA and maleilated chitosan, 185 or a hydrogel made of HA, poly(vinylphosphonic acid), and chitosan 186 ).…”

Bioactive hydrogels based on polysaccharides and peptides for soft tissue wound management

“…[53][54][55][56] Due to the lack of adhesive action, excessive swelling, and premature degradation upon contact with tissue, the mechanical properties of HA-based hydrogels are generally poor as wound repairing materials. These issues can be addressed by chemical modification of HA to improve the cross-linking degree of networks, and the interpenetration and entanglement of the polymer chains, including catechol [57][58][59][60][61][62][63] and pyrogallol 57,64 for musselinspired catechol chemistry through hydrogen-bond interaction and metal ions coordination, aldehydes from periodate oxidation of HA 60,[65][66][67][68][69] and photoactive o-nitrobenzyl [70][71][72][73] for Schiff base reaction, methacrylate 61,62,71,[74][75][76] for photoinitiated free radical polymerization, phenylboronic acid 77,78 for glucose-sensitive dynamic borate bond with polyphenol groups, etc.…”