Preparation of chitosan/hydrolyzed collagen/hyaluronic acid based hydrogel composite with caffeic acid addition

Trends in polysaccharide-based hydrogels and their role in enhancing the bioavailability and bioactivity of phytocompounds

Over the years, polysaccharides such as chitosan, alginate, hyaluronic acid, k-carrageenan, xanthan gum, carboxymethyl cellulose, pectin, and starch, alone or in combination with proteins and/or synthetic polymers, have been used to engineer an extensive portfolio of hydrogels with remarkable features. The application of polysaccharide-based hydrogels has the potential to alleviate challenges related to bioavailability, solubility, stability, and targeted delivery of phytocompounds, contributing to the development of innovative and efficient drug delivery systems and functional food formulations. This review highlights the current knowledge acquired on the preparation, features and applications of polysaccharide/phytocompounds hydrogel-based hybrid systems in wound management, drug delivery, functional foods, and food industry. The structural, functional, and biological requirements of polysaccharides and phytocompounds on the overall performance of such hybrid systems, and their impact on the application domains are also discussed.

Preparation and characterization of ternary polysaccharide hydrogels based on carboxymethyl cellulose, carboxymethyl chitosan, and carboxymethyl β-cyclodextrin

A series of ternary polysaccharide hydrogels were facile prepared by incorporating carboxymethyl cellulose (CMC) into the carboxymethyl chitosan/carboxymethyl β-cyclodextrin (CMCS/CMCD) complex solution based on multiple physical interactions. Structure properties of the CMC/CMCS/CMCD hydrogels were revealed by FTIR, XRD, SEM, and TG. The rheological and texture properties, temperature/pH-response behaviors, biocompatablity, and antimicrobial activity of the hydrogels were determined in detail. These results showed that the existence of electron force and hydrogen bond among three components leading to formation of the hydrogels, displaying good mechanical characteristic, stable solid-like rheological properties, controllable swelling and degradation behaviors, and excellent biocompatibility. Additionally, the swelling kinetics can be well described by the Schott's pseudo second order model. Moreover, the hydrogels loaded with cinnamic acid (CA) exhibited good antimicrobial activity against both Staphylococcus aureus and Escherichia coli, and the antimicrobial activity was related to the composition of the prepared hydrogels. The novel ternary polysaccharide hydrogels may have good application prospects in food and bio-medicine.

Co-assembly of cisplatin and dasatinib in hyaluronan nanogel to combat triple negative breast cancer with reduced side effects

Treatment for triple negative breast cancer (TNBC) remains a huge challenge due to the lack of targeted therapeutics and tumor heterogenicity. Cisplatin (Cis) have demonstrated favorable therapeutic response in TNBC and thus is used together with various kinase inhibitors to fight the heterogenicity of TNBC. The combination of Cis with SRC inhibitor dasatinib (DAS) has shown encouraging anti-TNBC efficacy although the additive toxicity was commonly observed. To overcome the severe side effects of this Cis involved therapy, here we co-encapsulated Cis and DAS into a self-assembled hyaluronan (HA) nanogel (designated as HA/Cis/DAS (HCD) nanogel) to afford the TNBC targeted delivery by using the 4T1 mouse model. The acquired HCD nanogel was around 181 nm in aqueous solution, demonstrating the pharmacological activities of both Cis and DAS. Taking advantages of HA's targeting capability towards CD44 that is overexpressed on many TNBC cells, the HCD could well maintain the anticancer efficacy of the Cis and DAS combination, significantly increase the maximum tolerated dose and relieve the renal toxicity in vivo. The current HCD nanogel provides a potent strategy to improve the therapeutic outcome of Cis and DAS combination and thus representing a new targeted treatment option for TNBC.

Exploring the Progress of Hyaluronic Acid Hydrogels: Synthesis, Characteristics, and Wide-Ranging Applications

This comprehensive review delves into the world of hyaluronic acid (HA) hydrogels, exploring their creation, characteristics, research methodologies, and uses. HA hydrogels stand out among natural polysaccharides due to their distinct features. Their exceptional biocompatibility makes them a top choice for diverse biomedical purposes, with a great ability to coexist harmoniously with living cells and tissues. Furthermore, their biodegradability permits their gradual breakdown by bodily enzymes, enabling the creation of temporary frameworks for tissue engineering endeavors. Additionally, since HA is a vital component of the extracellular matrix (ECM) in numerous tissues, HA hydrogels can replicate the ECM's structure and functions. This mimicry is pivotal in tissue engineering applications by providing an ideal setting for cellular growth and maturation. Various cross-linking techniques like chemical, physical, enzymatic, and hybrid methods impact the mechanical strength, swelling capacity, and degradation speed of the hydrogels. Assessment tools such as rheological analysis, electron microscopy, spectroscopy, swelling tests, and degradation studies are employed to examine their attributes. HA-based hydrogels feature prominently in tissue engineering, drug distribution, wound recovery, ophthalmology, and cartilage mending. Crafting HA hydrogels enables the production of biomaterials with sought-after qualities, offering avenues for advancements in the realm of biomedicine.

Functionalization of sterculia gum for making platform hydrogels via network formation for use in drug delivery

Recently, various advancements have been made in the development of functional polymeric materials for innovative applications. Herein this work, functionalization of sterculia gum (SG) was carried out via grafting of poly(2-(methacryloyloxy) ethyltrimethylammonium chloride) (METAC)-polyvinyl pyrrolidone (PVP) to develop hydrogel dressings as a platform for use in drug delivery (DD). The innovation of the present work is the exploration of inherent antioxidant and antimicrobial properties of the SG along with antimicrobial characteristic of poly(METAC) and PVP, to design the doxycycline encapsulated hydrogel dressings for better wound healing. FESEM, EDS and AFM analyzed the surface morphology of hydrogels. FTIR, 13C NMR and XRD inferred inclusion of poly(METAC)-PVP into polymers. 13C NMR confirmed the incorporation of poly(METAC) and PVP onto gum by the presence of a peak at 54.74 ppm because of methyl carbon attached to quaternary nitrogen of poly(METAC) and at 45.48 ppm due to the ring carbon of PVP along with FTIR peak at 949 cm-1 because of CN bending of quaternary nitrogen of poy (METAC). Thermal characterization of copolymers has been performed using TGA analysis. One gram of copolymeric hydrogel dressing absorbed 6.51 ± 0.03 g simulated salivary fluid (SSF) and 7.65 ± 0.03 g simulated wound fluid (SWF). Release of doxycycline drug occurred in a sustained manner and followed the Non-Fickian diffusion mechanism from hydrogels. The release profile was most effectively described by Hixon-Crowell kinetic model. Hydrogel demonstrated biocompatibility and expressed thrombogenicity 79.7 ± 4.9 % during its polymer-blood interactions. Copolymer revealed mucoadhesive property, requiring a force of 77.00 ± 0.01 mN to detach from bio-membrane. Additionally, it exhibited antioxidant features, showing 43.81 ± 0.286 % free radical scavenging. Hydrogel dressings were mechanically stable and revealed 0.76 ± 0.09 N mm-2 tensile strength and 9.18 ± 0.01 N burst strength. Polymer films were permeable to oxygen and water vapor and were impermeable to microorganisms. Hydrogel dressings exhibited antimicrobial properties against Pseudomonas aeruginosa and Staphylococcus aureus bacteria. Overall, these properties displayed the suitability of hydrogels for wound dressing (WD) applications which may actively enhance wound healing.

Cowberry extract loaded chitosan hydrogel with photothermal and antioxidant properties promotes infected wound healing

Bacterial infection and oxidative stress impede clinical wound healing. Herein, the plant-derived cowberry extract (CE) was first explored as a natural photothermal agent and antioxidant to deal with bacterial infection and oxidative stress. After loading in the carboxymethyl chitosan (CMCs)/oxidized dextran (Odex) hydrogel, the photothermal effect of CE was highly enhanced by CMCs. The controlled temperature induced by CE-containing hydrogel under NIR laser irradiation could rapidly (10 min) and effectively kill Staphylococcus aureus (S. aureus, 99.3 %) and Escherichia coli (E. coli, 94.6 %). Besides, this hydrogel exhibited a fast gelation and hemostasis abilities, high stability, adhesion and ROS scavenging capabilities, as well as good injectability and biocompatibility. Above superior properties make this hydrogel to accelerate the wound healing in S. aureus-infected mice, and it is expected to be a potential clinical wound dressing.

Mild hyperthermia-assisted chitosan hydrogel with photothermal antibacterial property and CAT-like activity for infected wound healing

Infected wounds pose a serious threat to public health and pose a significant challenge and financial burden worldwide. The treatment of infected wounds is now an urgent problem to be solved. Herein, mild hyperthermia-assisted hydrogels composed of carboxymethyl chitosan (CMCs), oxidized dextran (Odex), epigallocatechin gallate (EGCG) and PtNPs@PVP (CAT-like nanoenzymes) were proposed for the repair of infected wounds. The incorporation of PtNPs@PVP nanoenzymes give the hydrogels excellent photothermal property and CAT-like activity. When the temperature is maintained at 42-45 °C under 808 nm near infrared (NIR) exposure, the CMCs/Odex/EGCG/Nanoenzymes (COEN2) hydrogel demonstrated highly enhanced antibacterial ability (95.9 % in vivo), hydrogen peroxide (H2O2) scavenging ratio (85.1 % in vitro) and oxygen supply (20.7 mg/L in vitro). Furthermore, this mild-heat stimulation also promoted angiogenesis in the damaged skin area. Overall, this multifunctional hydrogel with antibacterial, antioxidant, oxygen supply, hemostasis, and angiogenesis capabilities has shown great promise in the repair of infected wounds. This study establishes the paradigm of enhanced infected wound healing by mild hyperthermia-assisted H2O2 scavenging, oxygen supplemental, and photothermal antibacterial hydrogels.

Feasibility of caffeic acid as a crosslinking agent in modifying acellular extracellular matrices

Acellular extracellular matrices (aECM) are commonly utilized, both experimentally and clinically, in the regenerative medicine field. However, some disadvantages such as rapid degradation, poor mechanical properties, chronic inflammatory reactions and low antioxidant activity have limited their further application. In this study the feasibility of caffeic acid as a crosslinking agent in fixing small intestinal submucosa (SIS) was evaluated. The ninhydrin assay, swelling ratio and FTIR spectra indicated that caffeic acid can efficiently react with free amino groups to crosslink SIS and the highest crosslinking index reached 21.60 ± 1.37%. Moreover, the shrinkage temperature of SIS remarkably increased from 59 °C to about 80 °C and the degradation rate of CA-SIS was all lower than 6%, demonstrating their improved biostability and hydrothermal stability. Importantly, the antioxidant activity of CA-SIS ranged from 55% to 90%, statistically higher than that of native SIS (37.33 ± 2.94%). Additionally the cytotoxicity test presented that the cytotoxicity grade of CA-SIS was 1 or 0, whilst large numbers of living HUVECs were attached to the surface of the material and exhibited high cell viability. These results indicated their excellent cytocompatibility. The data of subcutaneous implant displayed that the number of inflammatory cells in 2%- and 2.5%CA-SIS groups remained at a low level (below 100 cells/field) while that of the native SIS group continued increasing, finally reaching 142.33 ± 30.92 cells/field. In conclusion, caffeic acid is a promising candidate for modifying aECM and may play a vital role in the design and fabrication of tissue engineering scaffolds.

Synthesis and characterization of Hyaluronic Acid (HA) modified polymeric composite for effective treatment of wound healing by transdermal drug delivery system (TDDS)

The present study aimed to fabricate a novel polymeric spongy composite to enhance skin regeneration composed of Nystatin (antifungal agent) and Silver Nanoparticles (AgNps). Different formulations (F1-F8) were developed & characterized by using various analytical techniques. AgNps synthesized by chemical reduction method showed spherical morphology 2 µm in size showed by SEM and XRD. A fine porous structure of gel embedded with AgNps having an amorphous structure with 10 % crystallinity due to AgNps was found. IR spectra revealed no chemical interaction between polymers and Nystatin. An increase in thermal stability of formulation was observed till 700 ℃ analyzed by Differential Scanning Calorimetry. Cytotoxic analysis on L929 mouse skin fibroblast cells showed a decrease in cell viability as Ag concentration increased (inactivating Fibroblast and keratinocytes) while 10 mg composition was found safest concentration (94%). Optimized formulation (F2) presented in-vitro drug release up to 90.59% ± 0.76 at pH 7.4, swelling studies (87.5% ± 0.57), water retention (26.60 ± 0.34), pH (5.31 ± 0.03). In the animal burn model, the group that received CHG/Ag/Nystatin healed the wound significantly (p < 0.05). These results suggested that optimized carrier can be used for other anti-fungal drugs facilitating the early healing of the wound.

Ultra-stretchable, tissue-adhesive, shape-adaptive, self-healing, on-demand removable hydrogel dressings with multiple functions for infected wound healing in regions of high mobility

Bacterial infection in the most mobile area usually leads to delayed healing and functional restriction, which has been a long-term challenge in clinic. Developing hydrogel-based dressings with mechanical flexibly, high adhesive and anti-bacterial properties, will contribute to the healing and therapeutic effects especially for this typical skin wound. In this work, composite hydrogel named PBOF through multi-reversible bonds between polyvinyl alcohol, borax, oligomeric procyanidin and ferric ion demonstrated a 100 times ultra-stretch ability, 24 kPa of highly tissue-adhesive, rapid shape-adaptability within 2 min and self-healing feature within 40 s, was designed as the multifunctional wound dressing for the Staphylococcus aureus-infected skin wound in the mice nape model. Besides, this hydrogel dressing could be easily removed on-demand within 10 min by water. The rapid disassembly of this hydrogel is related to the formation of hydrogen bonds between polyvinyl alcohol and water. Moreover, the multifunctional properties of this hydrogel include strong anti-oxidative, anti-bacteria and hemostasis derived from oligomeric procyanidin and photothermal effect of ferric ion/polyphenol chelate. The killing ratio of the hydrogel on Staphylococcus aureus in infected skin wound reached 90.6% when exposed to 808 nm irradiation for 10 min. Simultaneously, reduced oxidative stress, suppressed inflammation, and promoted angiogenesis all together accelerated wound healing. Therefore, this well-designed multifunctional PBOF hydrogel holds great promise as skin wound dressing especially in the high mobile regions of the body. STATEMENT OF SIGNIFICANCE: An ultra-stretchable, highly tissue-adhesive, and rapidly shape-adaptive, self-healing and on-demand removable hydrogel based on multi-reversible bonds among polyvinyl alcohol, borax, oligomeric procyanidin and ferric ion is designed as dressing material for infected wound healing in the movable nape. The rapid on-demand removal of the hydrogel relates to the formation of hydrogen bonds between polyvinyl alcohol and water. This hydrogel dressing shows strong antioxidant capacity, rapid hemostasis and photothermal antibacterial ability. This is derived from oligomeric procyanidin and thephotothermal effect of ferric ion/polyphenol chelate, which eliminates bacterial infection, reduces oxidative stress, regulates inflammation, promotes angiogenesis, and finally accelerates the infected wound healing in movable part.

Synthesis, Characterization and Biological Properties of Type I Collagen-Chitosan Mixed Hydrogels: A Review

Type I collagen and chitosan are two of the main biological macromolecules used to design scaffolds for tissue engineering. The former has the benefits of being biocompatible and provides biochemical cues for cell adhesion, proliferation and differentiation. However, collagen hydrogels usually exhibit poor mechanical properties and are difficult to functionalize. Chitosan is also often biocompatible, but is much more versatile in terms of structure and chemistry. Although it does have important biological properties, it is not a good substrate for mammalian cells. Combining of these two biomacromolecules is therefore a strategy of choice for the preparation of interesting biomaterials. The aim of this review is to describe the different protocols available to prepare Type I collagen-chitosan hydrogels for the purpose of presenting their physical and chemical properties and highlighting the benefits of mixed hydrogels over single-macromolecule ones. A critical discussion of the literature is provided to point out the poor understanding of chitosan-type I collagen interactions, in particular due to the lack of systematic studies addressing the effect of chitosan characteristics.

Developing hyaluronic acid-proline-ferric ion cross-linked film for efficient wound healing application

A novel cross-linked film dressing that can accelerate wound healing and guard against bacterial infection was presented in this work. The hyaluronic acid-proline-ferric ion (HA-Pro-Fe³⁺) film was successfully prepared by physically cross-linking method, which the carboxyl groups of the HA and Pro molecules should be in coordination with Fe³⁺. The HA-Pro-Fe³⁺ cross-linked film showed three-dimensional porous structure, appropriate water vapor permeability and swelling property, favorable cytocompatibility and hemocompatibility, antibacterial and antioxidative capability. The results of rat skin wound healing confirmed that HA-Pro-Fe³⁺ film could accelerate epithelial regeneration and collagen deposition, promote angiogenesis and significantly improve skin wound healing. Elisa analysis indicated that HA-Pro-Fe³⁺ material could down-regulate the expression of IL-6 and TNF-α, and up-regulate the level of TGF-β₁ and VEGF. Given its biocompatibility, antibacterial ability, promotion of cell proliferation and angiogenesis, the wide application of HA-Pro-Fe³⁺ cross-linked film in wound repair would be anticipated.

A Schiff base hydrogel dressing loading extracts from Periplaneta Americana for diabetic wound healing

As a common complication of diabetic patients, the chronic wound of diabetes has a high incidence, expensive treatment, and recurrence probability, which causes long-term negative impacts on patients' daily life. In this study, the hydrogel was formed by Schiff base reaction between oxidized hyaluronic acid (OHA) and carboxymethyl chitosan (CMCS), and the composite hydrogel dressing was prepared by adding the active polypeptides extract of Periplaneta Americana (PAE). By mass spectrometer determined, PAE mainly includes vitellogenins that can trigger an immune response. The composite hydrogel has good swelling properties, proper fluidity, and a regular 3D network structure. The hydrogel has good cytocompatibility and can promote cell proliferation by L929 fibroblast assay. Finally, it was used to evaluate the effect of diabetic wound repair. The results showed that it could effectively promote wound healing, promote tissue and vascular regeneration, inhibit inflammatory factors, and promote the expression of growth factors. The OHA/CMCS/PAE hydrogels would be promising candidates for chronic wound healing applications.

Collagen-PVA Films Plasticized with Choline Acetate Ionic Liquid for Sustained Drug Release: UV Shielding, Mechanical, Antioxidant, and Antibacterial Properties

Collagen and poly(vinyl alcohol) films as topical drug delivery systems were developed by plasticization with glycerol and different concentrations of choline acetate ([Cho]Ac) ionic liquid (IL). The results showed that [Cho]Ac improved the performance of the materials and can serve as an alternative to synthetic plasticizers such as glycerol. Ciprofloxacin (CIP) was used as a model drug to study its release behavior. Ready-to-use films were characterized for their optical opacity, solubility, swelling, mechanical properties, water contact angle, surface morphology, surface roughness, antioxidant, and antimicrobial activities. Moreover, X-ray diffraction and Fourier Transform Infrared (FTIR) studies were carried out for molecular characterization of the films. [Cho]Ac used as a plasticizing agent showed excellent antioxidant properties, mechanical strength, and UV shielding properties. Further, [Cho]Ac improves the roughness and decreases the solubility of films. The in vitro release behavior of CIP was investigated at physiological pH (7.4), and the results showed that CIP was released in a more controlled manner due to the incorporation of [Cho]Ac into the films' matrix, while the films constructed with glycerol exhibited burst release of CIP. Moreover, the films loaded with CIP showed excellent antibacterial activity against Gram-negative (Escherichia coli) as well as Gram-positive (Staphylococcus aureus) bacteria. This study provides insight into the use of choline-based ILs as plasticizing agents for the fabrication of protein-polymer composite films for wound dressing and many other applications.

Polysaccharide-based biopolymer hydrogels for heavy metal detection and adsorption

BACKGROUND

With rapid development in agriculture and industry, water polluted with heavy metallic ions has come to be a serious problem. Adsorption-based methods are simple, efficient, and broadly used to eliminate heavy metals. Conventional adsorption materials have the problems of secondary environmental contamination. Hydrogels are considered effective adsorbents, and those prepared from biopolymers are biocompatible, biodegradable, non-toxic, safe to handle, and increasingly used to adsorb heavy metal ions.

AIM OF REVIEW

The natural origin and easy degradability of biopolymer hydrogels make them potential for development in environmental remediation. Its water absorption capacity enables it to efficiently adsorb various pollutants in the aqueous environment, and its internal pore channels increase the specific surface area for adsorption, which can provide abundant active binding sites for heavy metal ions through chemical modification.

KEY SCIENTIFIC CONCEPT OF REVIEW

As the most representative of biopolymer hydrogels, polysaccharide-based hydrogels are diverse, physically and chemically stable, and can undergo complex chemical modifications to enhance their performance, thus exhibiting superior ability to remove contaminants. This review summarizes the preparation methods of hydrogels, followed by a discussion of the main categories and applications of polysaccharide-based biopolymer hydrogels.

Use of vinasse and coffee waste as chelating agent of photo-Fenton landfill leachate treatment

This research studies the use of vinasse (VS) coming from Pisco and caffeic acid (Caa) from solid coffee waste as chelating agents of this process, to carry out a photo-Fenton process using UVc lamps of 254-nm wavelength for 60 min, at the natural pH of the landfill leachate (8.9). Without the chelating agent, there was a removal of UV 254 and COD of 54.2% and 54.7%, respectively, when the photo-Fenton reaction was carried out at pH 3; at pH 6, the removal of UV 254 and COD was 13.1% and 39.2%, respectively, and at pH 8.9, the elimination of UV 254 and COD was 10.8% and 16.1%, respectively. When Caa was used in the landfill leachate (LL) for the photo-catalytic processes carried out at pH 8.9, a removal of 24.1%, 43.0%, and 47.4% of UV 254 was obtained using 5 mg/L, 50 mg/L, and 100 mg/L of Caa. The removal of UV 254 was 27.3%, 30.7%, and 36.3% using 5 mg/L, 50 mg/L, and 100 mg/L of VS, respectively, and the removal of COD was 32.2%, 35.4%, and 39.2% using 5 mg/L, 50 mg/L, and 100 mg/L of VS, respectively. When Caa was used in the LL at pH 8.9, the concentration of total Fe went from 37.5 to 33.2, from 40.2 to 36.8, and from 45.2 to 42.1, using 5 mg/L, 50 mg/L, and 100 mg/L of caffeic acid, respectively. Using VS in the LL at pH 8.9, the concentration of total Fe along the run went from 35.1 to 32.2, from 39.4 to 34.8, and from 42.1 to 40.2, using 5 mg/L, 50 mg/L, and 100 mg/L of VS, respectively. As a result of these processes, it was noted that the use of Caa and VS increases the solubility of Fe at a higher pH.

Targeting therapy effects of composite hyaluronic acid/chitosan nanosystems containing inclusion complexes

In order to solve the difficulties in the treatment of Staphylococcus aureus infections, a novel enrofloxacin-cyclodextrin (β-CD) inclusion complexes (IC) containing hyaluronic acid/chitosan (HA/CS) self-assemble composite nanosystems covered by poloxamer 188 was designed in our previous study. In this study, the sustained release peforemance, targeting delivery, and therapy effects of the enrofloxacin-composite nanosystems were evaluated in vivo. The enrofloxacin-composite nanosystems had uniform size and smooth surface with drug loading capacity (LC) of 9.92 ± 0.3%. Thermogravimetric analysis (TGA) showed that the material used for the preparation of the enrofloxacin-composite nanosystems did not affect the thermal stability of enrofloxacin. Compared with enrofloxacin injection and enrofloxacin polymeric nanoparticles, the enrofloxacin-composite nanosystems had excellent sustained-release performance in vivo. The enrofloxacin-composite nanosystems have specific targeting to the infection site of Staphylococcus aureus. The excellent sustained release and targeting delivery properties ensure that the anti-infective treatment effect of the enrofloxacin-composite nanosystems in vivo was higher than that of enrofloxacin injection and enrofloxacin polymeric nanoparticles. It can more effectively promote the wound healing. These results suggest that our previous designed enrofloxacin-composite nanosystems will be a promising formulation for effective targeting therapy of Staphylococcus aureus infections.

Quercetin/Hydroxypropyl-β-Cyclodextrin Inclusion Complex-Loaded Hydrogels for Accelerated Wound Healing

This study concentrated on developing quercetin/cyclodextrin inclusion complex-loaded polyvinyl alcohol (PVA) hydrogel for enhanced stability and solubility. Quercetin was encapsulated in hydroxypropyl-β-cyclodextrin (HP-β-CD) by the solvent evaporation method. The prepared quercetin/HP-β-CD inclusion complex showed 90.50 ± 1.84% encapsulation efficiency (%EE) and 4.67 ± 0.13% loading capacity (%LC), and its successful encapsulation was confirmed by FT-IR and XRD. The quercetin/HP-β-CD inclusion complex was well dispersed in viscous solutions of PVA in various amounts (0.5, 1.0, 1.5. 2.5, and 5.0% w/v ratio), and the drug-loaded polymer solution was physically crosslinked by multiple freeze–thaw cycles to form the hydrogel. The cumulative amount of quercetin released from the prepared hydrogels increased with increasing concentrations of the inclusion complex. The introduction of the inclusion complex into the PVA hydrogels had no influence on their swelling ratio, but gelation and compressive strength reduced with increasing inclusion complex concentration. The potential cytotoxicity of quercetin/HP-β-CD inclusion complex hydrogels was evaluated by MTT assay and expressed as % cell viability. The results show biocompatibility toward NCTC 929 clone cells. The inhibitory efficacy was evaluated with 2, 2-diphenyl-1-picrylhydrazyl (DPPH) free radical scavenging assay, and the results show a higher level of antioxidant activity for quercetin/HP-β-CD inclusion complex hydrogels compared with free quercetin. The findings of our study indicate that the developed quercetin/HP-β-CD inclusion complex hydrogels possess the required properties and can be proposed as a quercetin delivery system for wound-healing applications.

Recent insights into polysaccharide-based hydrogels and their potential applications in food sector: A review

Hydrogels are ideal for various food applications because of their softness, elasticity, absorbent nature, flexibility, and hygroscopic nature. Polysaccharide hydrogels are particularly suitable because of the hydrophilic nature, their food compatibility, and their non-immunogenic character. Such hydrogels offer a wide range of successful applications such as food preservation, pharmaceuticals, agriculture, and food packaging. Additionally, polysaccharide hydrogels have proven to play a significant role in the formulation of food flavor carrier systems, thus diversifying the horizons of newer developments in food processing sector. Polysaccharide hydrogels are comprised of natural polymers such as alginate, chitosan, starch, pectin and hyaluronic acid when crosslinked physically or chemically. Hydrogels with interchangeable, antimicrobial and barrier properties are referred to as smart hydrogels. This review brings together the recent and relevant polysaccharide research in these polysaccharide hydrogel applications areas and seeks to point the way forward for future research and interventions. Applications in carrying out the process of flavor carrier system directly through their incorporation in food matrices, broadening the domain for food application innovations. The classification and important features of polysaccharide-based hydrogels in food processing are the topics of the current review study.

The Characterization of Scaffolds Based on Dialdehyde Chitosan/Hyaluronic Acid

In this work, two-component dialdehyde chitosan/hyaluronic acid scaffolds were developed and characterized. Dialdehyde chitosan was obtained by one-step synthesis with chitosan and sodium periodate. Three-dimensional scaffolds were prepared by the lyophilization method. Fourier transform infrared spectroscopy (FTIR) was used to observe the chemical structure of scaffolds and scanning electron microscopy (SEM) imaging was done to assess the microstructure of resultant materials. Thermal analysis, mechanical properties measurements, density, porosity and water content measurements were used to characterize physicochemical properties of dialdehyde chitosan/hyaluronic acid 3D materials. Additionally, human epidermal keratinocytes (NHEK), dermal fibroblasts (NHDF) and human melanoma cells (A375 and G-361) were used to evaluate cell viability in the presence of subjected scaffolds. It was found that scaffolds were characterized by a porous structure with interconnected pores. The scaffold composition has an influence on physicochemical properties, such as mechanical strength, thermal resistance, porosity and water content. There were no significant differences between cell viability proliferation of all scaffolds, and this observation was visible for all subjected cell lines.

Structural and biological investigation of chitosan/hyaluronic acid with silanized-hydroxypropyl methylcellulose as an injectable reinforced interpenetrating network hydrogel for cartilage tissue engineering

Cartilage damage continues to pose a threat to humans, but no treatment is currently available to fully restore cartilage function. In this study, a new class of composite hydrogels derived from water-soluble chitosan (CS)/hyaluronic acid (HA) and silanized-hydroxypropyl methylcellulose (Si-HPMC) (CS/HA/Si-HPMC) has been synthesized and tested as injectable hydrogels for cartilage tissue engineering when combined without the addition of a chemical crosslinking agent. Mechanical studies of CS/HA and CS/HA/Si-HPMC hydrogels showed that as Si-HPMC content increased, swelling rate and rheological properties were higher, compressive strength decreased and degradation was faster. Our results demonstrate that the CS and HA-based hydrogel scaffolds, especially the ones with 3.0% (w/v) Si-HPMC and 2.5/4.0% (w/v) CS/HA, have suitable physical performance and bioactive properties, thus provide a potential opportunity to be used for cartilage tissue engineering. In vitro studies of CS/HA and CS/HA/Si-HPMC hydrogels encapsulated in chondrocytes have shown that the proper amount of Si-HPMC increases the proliferation and deposition of the cartilage extracellular matrix. The regeneration rate of the CS/HA/Si-HPMC (3%) hydrogel reached about 79.5% at 21 days for long retention periods, indicating relatively good in vivo bone regeneration. These CS/HA/Si-HPMC hydrogels are promising candidates for tissue compatibility injectable scaffolds. The data provide proof of the principle that the resulting hydrogel has an excellent ability to repair joint cartilage using a tissue-engineered approach.

RESEARCH HIGHLIGHTS

An injectable hydrogel based on CS/HA/Si-HPMC composites was developed.

The CS/HA/Si-HPMC hydrogel displays the tunable rheological with mechanical properties.

The CS/HA/Si-HPMC hydrogel is highly porous with high swelling and degradation ratio.

Increasing concentration of Si-HPMC promote an organized network in CS/HA/Si-HPMC hydrogels.

Injectable CS/HA/Si-HPMC hydrogels have a high potential for cartilage tissue engineering.