Bacterial Nanocellulose-Enhanced Alginate Double-Network Hydrogels Cross-Linked with Six Metal Cations for Antibacterial Wound Dressing

Abstract

Alginate (Alg) and bacterial nanocellulose (BNC) have exhibited great potential in biomedical applications, especially wound dressing. Non-toxicity and a moisture-maintaining nature are common features making them favorable for functional dressing fabrication. BNC is a natural biopolymer that promotes major advances to the current and future biomedical materials, especially in a flat or tubular membrane form with excellent mechanical strength at hydrated state. The main drawback limiting wide applications of both BNC and Alg is the lack of antibacterial activity, furthermore, the inherent poor mechanical property of Alg leads to the requirement of a secondary dressing in clinical treatment. To fabricate composite dressings with antibacterial activity and better mechanical properties, sodium alginate was efficiently incorporated into the BNC matrix using a time-saving vacuum suction method followed by cross-linking through immersion in separate solutions of six cations (manganese, cobalt, copper, zinc, silver, and cerium). The results showed the fabricated composites had not only pH-responsive antibacterial activities but also improved mechanical properties, which are capable of acting as smart dressings. All composites showed non-toxicity toward fibroblast cells. Rat model evaluation showed the skin wounds covered by the dressings healed faster than by BNC.

Gradient bimetallic ion–based hydrogels for tissue microstructure reconstruction of tendon-to-bone insertion

“…The lastly released metal ions may be absorbed and metabolized by local tissues. The in vitro experiments have confirmed that the metal ion hydrogels, with a concentration of 0.05 M, had good biocompatibility, and this concentration of metal ions is always used to prepare bioactive hydrogels in the field of regenerative medicine ( 57 , 58 ).The results of the tissue morphology analysis after surgery, which included the liver, lung, and kidney, indicated that the implantation of hydrogel did not affect the tissue structure of these organs in the rat and showed that the released metal ions could be well metabolized by the body (fig. S16).…”

Functionalization of Aminoalkylsilane-Grafted Bacterial Nanocellulose with ZnO-NPs-Doped Pullulan Electrospun Nanofibers for Multifunctional Wound Dressing

“…It has been reported that a dressing with a hemolysis rate of below 5 is considered an ideal wound dressing. 16 3.8. Cell Viability and Cytotoxicity.…”

“…The hemolysis rate decreased when electrospun nanofibers of Pul-ZnO-NPs covered the surface of BNC. It has been reported that a dressing with a hemolysis rate of below 5 is considered an ideal wound dressing …”

“…Bacterial nanocellulose (BNC) is extracellularly produced mainly by Komagataeibacter xylinus . Due to the unique properties of BNC, such as high water-holding capability, excellent mechanical properties in a wet state, nontoxicity, and biocompatibility, it has been widely employed in the production of biomedical materials. − More interestingly, BNC provides high moisture permeability and high exudate absorption, which are important aspects of functional wound dressings . Impregnation of different chemical compounds such as glycerin, chitosan, and vaccarin and numerous chemical modifications of BNC such as oxidation, carboxymethylation, sulfation, amino grafting, etc., are the focus of innovative strategies aiming to meet different requirements of various biomaterials.…”

Fibrous Aerogels for Solar Vapor Generation

“…Unlike the mechanical or chemical treatment of cellulose extracted from plants, the nanocellulose directly produced by certain aerobic bacterial species called bacterial nanocellulose (BNC) and possesses high crystallinity (up to 90%) and fewer impurities ( Yamanaka et al, 1989 ; Shahriari-Khalaji et al, 2020 ). With adequate sugar and oxygen in the medium for fermentation, BNC is generated in forms of 3D interconnected nanofibrous network with a diameter ranging from 20 to 100 nm.…”