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The constantly accelerating occurrence of microbial infections and their antibiotic resistance has spurred advancement in the field of material sciences and has guided the development of novel materials with anti-bacterial properties. To address the clinical exigencies, the material of choice should be biodegradable, biocompatible, and able to offer prolonged antibacterial effects. As an attractive option, hydrogels have been explored globally as a potent biomaterial platform that can furnish essential antibacterial attributes owing to its three-dimensional (3D) hydrophilic polymeric network, adequate biocompatibility, and cellular adhesion. The current review focuses on the utilization of different antimicrobial hydrogels based on their sources (natural and synthetic). Further, the review also highlights the strategies for the generation of hydrogels with their advantages and disadvantages and their applications in different biomedical fields. Finally, the prospects in the development of hydrogels-based antimicrobial biomaterials are discussed along with some key challenges encountered during their development and clinical translation. [ABSTRACT FROM AUTHOR]

Over the past few decades, hydrogel systems using natural polymers have been expansively employed in drug delivery applications. Among the various reported biopolymer-based hydrogel drug delivery systems, pectin (Pec) is an exceptional natural polymer due to its unique functionalities and excellent properties such as biocompatibility, biodegradability, low-cost, and simple gelling capability, which has received considerable interest in the drug delivery fields. Since there is an increasing need for biomaterials with unique properties for drug delivery applications, in this review, hydrogels fabricated from natural pectin polymers were thoroughly investigated. Additionally, the present mini review aims to bring collectively more concise ways such as sources, extraction, properties, and various forms of Pec based hydrogel drug delivery systems and their toxicity concerns are summarized. Finally, the potential objectives and challenges based on pectin-based hydrogel drug delivery systems are also discussed. [ABSTRACT FROM AUTHOR]

In this article, biodegradable tragacanth gum (TG) biopolymer based silver nanocomposite hydrogels (SNCHs) were prepared with acrylamide as monomer using a simple redox polymerization method. TG acts as stabilizer to produce uniform and large silver nanoparticles (Ag-NPs) in presence of Terminalia chebula (TC) leaf extract in the hydrogel network. Forier transform infrared spectroscopy demonstrated the structural units of functional groups of polymeric backbone of the hydrogels. The formation of Ag-NPs in TG based hydrogels was confirmed by UV–Vis spectra. The morphology of homogeneously dispersed Ag-NPs throughout hydrogel networks was confirmed by scanning electron microscopy. TEM analysis indicates that Ag-NPs with average diameters of around 5 nm formed within the hydrogel networks. The evaluation of antibacterial activity of Ag-NPs performed against gram-negative Escherichia coli and gram-positive Bacillus subtilis bacteria and obtained results proved that these newly developed hydrogels have great potential for use in wound healing as well as water purification applications. [ABSTRACT FROM AUTHOR]

Bacterial nanocellulose (BNC, as exopolysaccharide) synthesized by some specific bacteria strains is a fascinating biopolymer composed of the three-dimensional pure cellulosic nanofibrous matrix without containing lignin, hemicellulose, pectin, and other impurities as in plant-based cellulose. Due to its excellent biocompatibility (in vitro and in vivo), high water-holding capacity, flexibility, high mechanical properties, and a large number of hydroxyl groups that are most similar characteristics of native tissues, BNC has shown great potential in tissue engineering applications. This review focuses on and discusses the efficacy of BNC- or BNC-based biomaterials for hard tissue regeneration. In this review, we provide brief information on the key aspects of synthesis and properties of BNC, including solubility, biodegradability, thermal stability, antimicrobial ability, toxicity, and cellular response. Further, modification approaches are discussed briefly to improve the properties of BNC or BNC-based structures. In addition, various biomaterials by using BNC (as sacrificial template or matrix) or BNC in conjugation with polymers and/or fillers are reviewed and discussed for dental and bone tissue engineering applications. Moreover, the conclusion with perspective for future research directions of using BNC for hard tissue regeneration is briefly discussed. [ABSTRACT FROM AUTHOR]

The engineering of tissues under a three-dimensional (3D) microenvironment is a great challenge and needs a suitable supporting biomaterial-based scaffold that may facilitate cell attachment, spreading, proliferation, migration, and differentiation for proper tissue regeneration or organ reconstruction. Polysaccharides as natural polymers promise great potential in the preparation of a three-dimensional artificial extracellular matrix (ECM) (i.e., hydrogel) via various processing methods and conditions. Natural polymers, especially gums, based upon hydrogel systems, provide similarities largely with the native ECM and excellent biological response. Here, we review the origin and physico-chemical characteristics of potentially used natural gums. In addition, various forms of scaffolds (e.g., nanofibrous, 3D printed-constructs) based on gums and their efficacy in 3D cell culture and various tissue regenerations such as bone, osteoarthritis and cartilage, skin/wound, retinal, neural, and other tissues are discussed. Finally, the advantages and limitations of natural gums are precisely described for future perspectives in tissue engineering and regenerative medicine in the concluding remarks. [ABSTRACT FROM AUTHOR]

Bacterial cellulose (BC), an extracellular polysaccharide, is a versatile biopolymer due to its intrinsic physicochemical properties, broad-spectrum applications, and remarkable achievements in different fields, especially in the biomedical field. Presently, the focus of BC-related research is on the development of scaffolds containing other materials for in-vitro and in-vivo biomedical applications. To this end, prime research objectives concern the biocompatibility of BC and the development of three-dimensional (3D) BC-based scaffolds. This review summarizes the techniques used to develop 3D BC scaffolds and discusses their potential merits and limitations. In addition, we discuss the various biomedical applications of BC-based scaffolds for which the 3D BC matrix confers desired structural and conformational features. Overall, this review provides comprehensive coverage of the idea, requirements, synthetic strategies, and current and prospective applications of 3D BC scaffolds, and thus, should be useful for researchers working with polysaccharides, biopolymers, or composite materials. • Fabrication of 3-dimensional (3D) bacterial cellulose (BC) scaffolds • Impregnation of reinforcement materials for enhanced biocompatibility of 3D BC scaffolds • Practical biomedical applications of 3D BC scaffolds • Current challenges and future perspectives of 3D BC scaffolds [ABSTRACT FROM AUTHOR]

Advances in polymers have made significant contribution in diverse application oriented fields. Multidisciplinary applicability of polymers generates a range of strategies, which is pertinent in a wide range of fields. Blends of natural and synthetic polymers have spawned a different class of materials with synergistic effects. Specifically, poly (vinyl alcohol) (PVA) and alginate (AG) blends (PVAG) have demonstrated some promising results in almost every segment, ranging from biomedical to industrial sector. Combination of PVAG with other materials, immobilization with specific moieties and physical and chemical crosslinking could result in amendments in the structure and properties of the PVAG matrices. Here, we provide an overview of the recent developments in designing PVAG based matrix and complexes with their structural and functional properties. The article also provides a comprehensive outline on the applicability of PVAG matrix in wastewater treatment, biomedical, photocatalysis, food packaging, and fuel cells and sheds light on the challenges that need to be addressed. Finally, the review elaborates the future prospective of PVAG matrices in other unexplored fields like aircraft industry, nuclear science and space exploration. [Display omitted] [ABSTRACT FROM AUTHOR]

The controlled delivery of the desired bioactive molecules is required to achieve the maximum therapeutic effects with minimum side effects. Biopolymer-based hydrogels are ideal platforms for delivering the desired molecules owing to their superior biocompatibility, biodegradability, and low-immune response. However, the prolonged delivery of the drugs through biopolymer-based hydrogels is restricted due to their weak mechanical stability. We developed mechanically tough and biocompatible hydrogels to address these limitations using carboxymethyl chitosan, sodium alginate, and nanocellulose for sustained drug delivery. The hydrogels were cross-linked through calcium ions to enhance their mechanical strength. Nanocellulose-added hydrogels exhibited improved mechanical strength (Young's modulus; 23.36 → 30.7 kPa, Toughness; 1.39 → 5.65 MJm−3) than pure hydrogels. The composite hydrogels demonstrated increased recovery potential (66.9 → 84.5 %) due to the rapid reformation of damaged polymeric networks. The hydrogels were stable in an aqueous medium and demonstrated reduced swelling potential. The hydrogels have no adverse effects on embryonic murine fibroblast (3 T3), showing their biocompatibility. No bacterial growth was observed in hydrogels-treated groups, indicating their antibacterial characteristics. The sustained drug released was observed from nanocellulose-assisted hydrogel scaffolds compared to the pure polymer hydrogel scaffold. Thus, hydrogels have potential and could be used as a sustained drug carrier. [Display omitted] • The mechanically stable hydrogels were successfully synthesized using CMCS, SA, and nanocellulose. • The composite hydrogels showed improved storage modulus (~15 times) and decreased swelling potential. • The composite hydrogels exhibited enhanced biocompatibility and antibacterial. • Drug release behavior was profoundly affected by the pH of the medium. • The sustained drug release was observed in the composite hydrogel scaffolds. [ABSTRACT FROM AUTHOR]

• Starch-reduced graphene oxide (SRGO) was hydrothermally synthesized using soluble starch. • SRGO functionalized with amylose accommodates polyiodide to form SRGO–polyiodide nanocomposites (NCs) • SRGO–PI NC has strong antibacterial activity against Escherichia coli and Staphylococcus aureus. • Iodine-doped graphene NCs can be used for the sustained release of iodine/polyiodide. • Starch-based antibacterial nanomaterials incorporated with dopants can be used in food packaging. Graphene-based nanocomposites with superior antibacterial activity are highly sought after by the food packaging industries. Here, we report for the first time a method that utilizes soluble starch biopolymer as a functionalizing and reducing agent for the preparation of starch-reduced graphene oxide (SRGO), whereby polyiodide binds to the helical structures of amylose units of the starch (chromophore) to form a SRGO–polyiodide nanocomposite (SRGO–PI NC). UV–visible spectroscopy, X-ray diffraction, Raman spectroscopy, scanning electron microscopy, and energy-dispersive spectroscopy confirmed the presence of polyiodide in SRGO. SRGO–PI NC exhibited good antibacterial activities against pathogenic Gram-negative (Escherichia coli) and Gram-positive (Staphylococcus aureus) microbes with minimum inhibitory concentrations (MICs) and minimum bactericidal concentration (MBC) values (as determined by a broth-dilution method) of 2.5 and 5 mg/ml, respectively, for both E. coli and S. aureus. PrestoBlue viability assays showed half-maximal inhibitory concentration (IC 50) values of 0.45 and 0.41 mg/ml for E. coli and S. aureus , respectively. Time-kill kinetic and live/dead bacterial viability assays revealed the antimicrobial activities of SRGO-PI NC against both E. coli and S. aureus. The study provides new insights regarding the utilization of graphene–polyiodide NCs as high-efficacy antibacterial starch-based nanomaterials for food packaging applications. [ABSTRACT FROM AUTHOR]

In this study, non-animal mushroom carboxymethyl chitosan (NAM-CMCS) was used as a natural polymer stabilizing agent in the ultrasonic preparation of a ZnO nanocomposite at ambient laboratory temperatures. The formation and morphology of the ZnO nanoparticles were investigated by applying FTIR, XRD, XPS, FE-SEM, and DLS techniques. The FTIR and XPS spectra confirmed the presence of NAM-CMCS functional groups and ZnO in the nanoparticles. The prepared NAM-CMCS-ZnO nanoparticles were shown by FE-SEM to have a spherical shape and an average diameter of 18 ± 3.6 nm. The DLS-determined size distribution showed the NAM-CMCS-ZnO nanoparticle size averaged 21 ± 2.9 nm. Finally, cytocompatibility, hemostasis, and antibacterial performance were assessed in vitro to evaluate the biological performance of NAM-CMCS-ZnO nanoparticles. In vitro Prestoblue® assay and live/dead test results from skin fibroblast and keratinocytes confirmed the developed NAM-CMCS-ZnO nanoparticles were biocompatible over a wide range of concentrations (0–500 μg/well). The NAM-CMCS-ZnO nanoparticles exhibited synergetic antibacterial properties against Gram-positive (Staphylococcus aureus) bacteria. Moreover, the nanoparticles showed hemostatic properties with good hemocompatibility. The overall excellent biological properties of NAM-CMCS-ZnO nanoparticles indicate its suitability for use in wound dressing applications. [ABSTRACT FROM AUTHOR]

Hydrogels have immense potential in revolutionizing central nervous system (CNS) drug delivery, improving outcomes for neurological disorders. They serve as promising tools for controlled drug delivery to the CNS. Available hydrogel types include natural macromolecules (e.g., chitosan, hyaluronic acid, alginate), as well as hybrid hydrogels combining natural and synthetic polymers. Each type offers distinct advantages in terms of biocompatibility, mechanical properties, and drug release kinetics. Design and engineering considerations encompass hydrogel composition, crosslinking density, porosity, and strategies for targeted drug delivery. The review emphasizes factors affecting drug release profiles, such as hydrogel properties and formulation parameters. CNS drug delivery applications of hydrogels span a wide range of therapeutics, including small molecules, proteins and peptides, and nucleic acids. However, challenges like limited biodegradability, clearance, and effective CNS delivery persist. Incorporating 3D bioprinting technology with hydrogel-based CNS drug delivery holds the promise of highly personalized and precisely controlled therapeutic interventions for neurological disorders. The review explores emerging technologies like 3D bioprinting and nanotechnology as opportunities for enhanced precision and effectiveness in hydrogel-based CNS drug delivery. Continued research, collaboration, and technological advancements are vital for translating hydrogel-based therapies into clinical practice, benefiting patients with CNS disorders. This comprehensive review article delves into hydrogels for CNS drug delivery, addressing their types, design principles, applications, challenges, and opportunities for clinical translation. [ABSTRACT FROM AUTHOR]

Hydrogels are three-dimensional networks of polymer chains containing large amounts of water in their structure. Hydrogels have received significant attention in biomedical applications owing to their attractive physicochemical properties, including flexibility, softness, biodegradability, and biocompatibility. Different natural and synthetic polymers have been intensely explored in developing hydrogels for the desired applications. Biopolymers-based hydrogels have advantages over synthetic polymers regarding improved cellular activity and weak immune response. These properties can be further improved by grafting with other polymers or adding nanomaterials, and they structurally mimic the living tissue environments, which opens their broad applicability. The hydrogels can be physically or chemically cross-linked depending on the structure. The use of different biopolymers-based hydrogels in biomedical applications has been reviewed and discussed earlier. However, no report is still available to comprehensively introduce the synthesis, advantages, disadvantages, and biomedical applications of biopolymers-based hydrogels from the material point of view. Herein, we systematically overview different synthesis methods of hydrogels and provide a holistic approach to biopolymers-based hydrogels for biomedical applications, especially in bone regeneration, wound healing, drug delivery, bioimaging, and therapy. The current challenges and prospects of biopolymers-based hydrogels are highlighted rationally, giving an insight into the progress of these hydrogels and their practical applications. [Display omitted] [ABSTRACT FROM AUTHOR]

The development of novel biopolymers with improved functioning, gaseous barrier abilities, and prolonged shelf life will be possible through the creation of innovative technologies in food packaging. The protein-based polymers have shown unique physical and chemical features for the formation of film/coatings. Additionally, these biopolymeric materials can be functionalized with various additives and fillers such as plasticizers, metal/metal oxide nanoparticles, antioxidants, and antibacterial molecules. The incorporation of these additives and fillers in films/coatings successfully prevent or delays microbial growth and lipid oxidation, assuring food safety to ensure and extending the shelf-life of foods. Advancements in the manufacturing technologies such as solvent casting, 3-D printing, melt extrusion, electrospinning, and layer-by-layer assembly can be adapted to fabricate food packaging films, addressing consumer needs for convenience and portability. This review will present the current situation with protein-based films for sustainable use in food packaging applications. In addition, the individual protein used for film formation are discussed further nanofillers and additives used with protein films are mentioned. • Protein-based biopolymers have unique features depending on their origin and sources. • These films have been incorporated with other ingredients with the aim to enhance their physical and mechanical properties. • The incorporation of Nanomaterials, antibacterial and antioxidant agents have been seen to drive a bright future in biodegradable films. [ABSTRACT FROM AUTHOR]

Hydrogels have emerged as a versatile platform for a numerous biomedical application due to their ability to absorb a huge quantity of biofluids. In order to design hydrogels, natural polymers are an attractive option owing to their biocompatibility and biodegradability. Due to abundance in occurrence, cost effectiveness, and facile crosslinking approaches, alginate has been extensively investigated to fabricate hydrogel matrix. Management of cancer and chronic wounds have always been a challenge for pharmaceutical and healthcare sector. In both cases, curcumin have been shown significant improvement and effectiveness. However, the innate restraints like poor bioavailability, hydrophobicity, and rapid systemic clearance associated with curcumin have restricted its clinical translations. The current review explores the cascade of research around curcumin encapsulated alginate hydrogel matrix for wound healing and cancer therapy. The focus of the review is to emphasize the mechanistic effects of curcumin with its fate inside the cells. Further, the review discusses different approaches to designed curcumin loaded alginate hydrogels along with the parameters that regulates their release behavior. Finally, the review is concluded with emphasize on some key aspect on increasing the efficacy of these hydrogels along with novel strategies to further develop curcumin loaded alginate hydrogel matrix with multifacet applications. [ABSTRACT FROM AUTHOR]

A new method has been employed for preparation of silver nanoparticles (Ag-NPs) in polyelectrolyte hydrogels (PEHs) composed from polysaccharides such as xanthan gum (XG) and chitosan (CS) without using other organic solvents and reagents. The present study allows a simple and ecofriendly synthesis of Ag-NPs within PEHs network and were confirmed by UV–visible spectra with characteristic surface plasmon band in the range of 398–409 nm using different concentrations of silver ions. Highly controllable Ag-NPs with diameters of around 5–20 nm were obtained in PEHs with spherical shape. Scanning electron microscopy results confirmed that the Ag-NPs were formed homogeneously in the PEHs. Antibacterial activity of PEHs containing Ag-NPs has a great inhibition towards both gram-positive Staphylococcus aureus and negative-bacteria Escherichia coli . In vitro cytotoxicity and cell attachment studies with NIH 3T3 fibroblast cells on PEHs showed good cytocompatibile and that may be possibly used in antibacterial wound dressing applications. [ABSTRACT FROM AUTHOR]