Rapid Synthesis of Robust Antibacterial and Biodegradable Hydrogels via Frontal Polymerization

Abstract

Chitosan (CS) is widely used in biomedical hydrogels due to their similarity to extracellular matrix. However, the preparation method of CS-based hydrogel suffers the drawbacks of tedious operation, time-consuming and energy consumption. Thus, there is an urgent need to develop a rapid synthesis pathway towards hydrogels. In this work, we used a modified CS as a cross-linking agent and acrylic acid (AA) as monomer to prepare a hydrogel through frontal polymerization (FP), which facilitates a facile and rapid method achieved in several minutes. The occurrence of pure FP was confirmed via the frontal velocity and temperature profile measurement. In addition, the as-prepared hydrogel shows excellent mechanical strength up to 1.76 MPa, and the Young’s modulus (ranging from 0.16 to 0.56 MPa) is comparable to human skin. The degradation mechanism is revealed by the micro-IR images through the distribution of the functional groups, which is attributed to the breakage of the ether bond. Moreover, the hydrogel exhibits excellent degradability, biocompatibility and antibacterial properties, offering great potentials in tissue engineering. We believe this work not only offers a facile and rapid FP method to fabricate a robust degradable hydrogel, but also provides an effective pathway for the investigation of the degradation mechanism at the chemical bond analysis level.

Structure Effects on Swelling Properties of Hydrogels Based on Sodium Alginate and Acrylic Polymers

“…The synthesis of new hydrogel structures based on synthetic polymers and polysaccharides has been the subject of numerous studies. The most commonly used polysaccharides include chitosan [10,11], alginate [9,[12][13][14], starch [15][16][17], cellulose [18], carboxymethylcellulose [19,20], hyaluronic acid [21], etc. These biopolymers have several desirable features, such as being abundant, inexpensive, renewable, biodegradable, polyfunctional, highly reactive chemically, and possessing a wide variety of properties as well as adsorption capacities [15,22,23].…”

“…However, the addition of sodium alginate is relatively low in all studies published to date. It is usually 5-10 wt% relative to the amount of acrylic monomer [11,37,38]. In order to determine the properties of polyacrylic acid and SA based hydrogels at a much higher renewable polymer content, in our study, hydrogels with SA content of up to 33 wt% were prepared.…”