Cytocompatible, Injectable, and Electroconductive Soft Adhesives with Hybrid Covalent/Noncovalent Dynamic Network

Abstract

Synthetic conductive biopolymers have gained increasing interest in tissue engineering, as they can provide a chemically defined electroconductive and biomimetic microenvironment for cells. In addition to low cytotoxicity and high biocompatibility, injectability and adhesiveness are important for many biomedical applications but have proven to be very challenging. Recent results show that fascinating material properties can be realized with a bioinspired hybrid network, especially through the synergy between irreversible covalent crosslinking and reversible noncovalent self‐assembly. Herein, a polysaccharide‐based conductive hydrogel crosslinked through noncovalent and reversible covalent reactions is reported. The hybrid material exhibits rheological properties associated with dynamic networks such as self‐healing and stress relaxation. Moreover, through fine‐tuning the network dynamics by varying covalent/noncovalent crosslinking content and incorporating electroconductive polymers, the resulting materials exhibit electroconductivity and reliable adhesive strength, at a similar range to that of clinically used fibrin glue. The conductive soft adhesives exhibit high cytocompatibility in 2D/3D cell cultures and can promote myogenic differentiation of myoblast cells. The heparin‐containing electroconductive adhesive shows high biocompatibility in immunocompetent mice, both for topical application and as injectable materials. The materials could have utilities in many biomedical applications, especially in the area of cardiovascular diseases and wound dressing.

Bioinspired Double‐Dynamic‐Bond Crosslinked Bioadhesive Enables Post‐Wound Closure Care

“…These bioadhesives can be conveniently applied through injection and have sufficient adhesive strength as well as low toxicity. [ 1,2,8–10 ] However, the time between wound closure and complete healing is quite long—typically several days to weeks, [ 3 ] and during this post‐wound closure time, the closed wounds still need to be cared for to facilitate better wound healing. For example, after a wound is closed, it may need further handling, such as changing or adding medicines, according to the state of healing, which requires painlessly changing or removing the applied bioadhesives.…”

Self‐Healing, High Adherent, and Antioxidative LbL Multilayered Film for Enhanced Cell Adhesion

“…The low water contact angle of the (CCS‐R/OALG‐D) 15 film is 33.9° in Figure 3a, which represents its so high wettability that it is easier to spread water on the surface of the film. Besides making the damaged parts swell, water provides a certain fluidity to the damaged sections of the film, re‐activating the dynamic reversible interaction including Schiff base covalent bond [ 22 ] of the (CCS‐R/OALG‐D) 15 film, electrostatic interaction of –COO − and –NH 4 + as well as hydrogen bond, and these bridged bonds of the contact parts of the film can restore the original structure (Figure 1b). Consequently, the self‐healing ability of the (CCS‐R/OALG‐D) 15 film could be applied for wound healing, issue engineering repair and regeneration besides the enhancement of its service lifetime and reliability.…”

Recent Advances on Magnetic Sensitive Hydrogels in Tissue Engineering

“…Recently, the magnetic hydrogels as injectable systems have displayed great potential for tissue repair and magnetic drug targeting. Various kinds of cells and molecules can be encapsulated homogeneously into the magnetic hydrogels and then targeted to the pathological sites with minimal invasiveness (Wu et al, 2018;Chen X. et al, 2019b;Shi et al, 2019;Wu H. et al, 2019;Xu et al, 2019). Several polymers, including ionic-response polymers (e.g., sodium alginate), natural biocompatible polymers (e.g., chitosan), and synthetic polymers (e.g., polyacrylic acid), conjugated with the magnetic particles have been used to fabricate the injectable hydrogels for therapeutic applications (Jalili et al, 2017;Hu et al, 2018;Amini-Fazl et al, 2019).…”