Cellulose-Based Hydrogels for Wound Healing

Survey of Sustainable Wearable Strain Sensors Enabled by Biopolymers and Conductive Organic Polymers

The field of wearable sensors has evolved with operating devices capable of measuring biomechanics and biometrics, and detecting speech. The transduction, being the conversion of the biosignal to a measurable and quantifiable electrical signal, is governed by a conductive organic polymer. Meanwhile, the conformality of skin to the substrate is quintessential. Both the substrate and the conductive polymer must work in concert to reversibly deform with the user's movements for motion tracking. While polydimethylsiloxane shows mechanical compliance as a sensor substrate, it is of environmental interest to replace it with sustainable and degradable alternatives. As both the bulk of the weight and area of the sensor consist of the substrate, using renewable and biodegradable materials for its preparation would be an important step toward improving the lifecycle of wearable sensors. This review highlights wearable resistive sensors that are prepared from naturally occurring polymers that are both sustainable and biodegradable. Conductive polythiophenes are also presented, as well as how they are integrated into the biopolymer for sensors showing mechanical compliance with skin. This polymer is highlighted because of its structural conformality, conductivity, and processability, ensuring it fulfils the requirements for its use in sensors without adversely affecting the overall sustainability and biodegradability of resistive sensors. Different sustainable resistive sensors are also presented, and their performance is compared to conventional sensors to illustrate the successful integration of the biosourced polymers into sensors without comprising the desired elasticity and sensitivity to movement. The current state-of-the-art in sustainable resistive sensors is presented, along with knowledge of how biopolymers from different fields can be leveraged in the rational design of the next generation of sustainable sensors that can potentially be composted after their use.

Cellulose-based hydrogels enhanced with bioactive molecules for optimal chronic diabetic wound management

Hydrogels are three-dimensional structures that replicate natural tissues' extracellular matrix (ECM). They are essential for transporting exudates, gases, and moisture and facilitating cellular interactions in tissue engineering and wound healing. The choice of primary material in designing the scaffold is necessary to be paid more attention rather than common sources, including plant fibres like cotton, bamboo, and algae, as well as bacterial and marine-derived materials. Among them, cellulose-based polymers are especially valued for their biocompatibility and ability to promote wound healing. Chronic diabetic wounds pose unique treatment challenges, such as necrosis and infection risks. Consequently, a growing interest is in incorporating bioactive molecules into cellulose-based hydrogels. This article investigates how these infused hydrogels enhance the healing process in chronic diabetic wounds, examining various loading and crosslinking techniques alongside their clinical applications. It also discusses the benefits and limitations of bioactive molecules and their interactions with hydrogels to improve treatment strategies.

Macro-Size Regenerated Cellulose Fibre Embedded with Graphene Oxide with Antibacterial Properties

Macro-size regenerated cellulose fibres (RCFs) with embedded graphene oxide (GO) were fabricated by dissolving cellulose in a pre-cooled sodium hydroxide (NaOH)/urea solution and regenerated in sulphuric acid (H₂SO₄) coagulant. Initially, GO was found to disperse well in the cellulose solution due to intercalation with the cellulose; however, this cellulose-GO intercalation was disturbed during the regeneration process, causing agglomeration of GO in the RCF mixture. Agglomerated GO was confirmed at a higher GO content under a Dino-Lite microscope. The crystallinity index (CrI) and thermal properties of the RCFs increased with increasing GO loadings, up to 2 wt.%, and reduced thereafter. Cellulose-GO intercalation was observed at lower GO concentrations, which enhanced the crystallinity and thermal properties of the RCF-GO composite. It was shown that the GO exhibited antibacterial properties in the RCF-GO composite, with the highest bacterial inhibition against E. coli and S. aureus.

Cellulose: A Fascinating Biopolymer for Hydrogel Synthesis

The growing environmental concerns and increasing demands for eco-friendly materials have obliged researchers worldwide to explore naturally occurring biopolymers for various applications. Cellulose is a non-exhaustible polysaccharide biopolymer available almost...

Recent advancements in cellulose-based biomaterials for management of infected wounds

INTRODUCTION

Chronic wounds are a substantial burden on the healthcare system. Their treatment requires advanced dressings, which can provide a moist wound environment, prevent bacterial infiltration, and act as a drug carrier. Cellulose is biocompatible, biodegradable, and can be functionalized according to specific requirements, which makes it a highly versatile biomaterial. Antimicrobial cellulose dressings are proving to be highly effective against infected wounds.

AREAS COVERED

This review briefly addresses the mechanism of wound healing and its pathophysiology. It also discusses wound infections, biofilm formation, and progressive emergence of drug-resistant bacteria in chronic wounds and the treatment strategies for such types of infected wounds. It also summarizes the general properties, method of production, and types of cellulose wound dressings. It explores recent studies and advancements regarding the use of cellulose and its derivatives in wound management.

EXPERT OPINION

Cellulose and its various functionalized derivatives represent a promising choice of wound dressing material. Cellulose-based dressings loaded with antimicrobials are very useful in controlling infection in a chronic wound. Recent studies showing its efficacy against drug-resistant bacteria make it a favorable choice for chronic wound infections. Further research and large-scale clinical trials are required for better clinical evidence of its efficiency.