Gels最新文献

The main goal of this work was to develop nanoparticles of lysozyme (Lys) for biological and biomedical applications. The developed biosystems were based on Lys-loaded calcium alginate 2% and chitosan 1% beads and films with different concentrations of each polymer. Encapsulation efficiency was 100%. The ratio of adsorbed Lys on the films, Lys activity, and the release profile of Lys were measured using water and buffer solution at pH similar to the environment of cancer cells, at a controlled temperature of 37 °C and a constant speed, to assess the efficacy of the encapsulation process. Lys antimicrobial activity was assessed using Micrococcus lysodeikticus. Moreover, the anti-inflammatory and antioxidant properties of the developed biosystems were also evaluated. The anti-inflammatory activity of Lys released from calcium alginate 2%-chitosan 1% beads loaded with Lys was about 99%. These findings highlight the potential of the developed beads and films for biomedical applications, particularly in antimicrobial and anti-inflammatory therapies.

Drugs and drug candidate compounds commonly suffer from poor solubility and permeability. One promising strategy to mediate these drawbacks is use of novel solvents, such as deep eutectic compositions. The present research aims to determine the applicability of this approach for therapeutic metal complexes on the example of [Cu(Fur)₂(Phen)] (Fur = furoate-anion, Phen = 1,10-phenantroline) and [Cu(Fur)₂(Neoc)(H₂O)] (Fur = furoate-anion, Neoc = 2,9-dimetyl-1,10-phenanthroline) with molar weight of appx. 500 Da. Interaction of the metal complexes with the deep eutectic solvent (DES) reline was studied using electron paramagnetic resonance (EPR). Minimal inhibitory concentrations of the complexes dissolved in DES and dimethyl sulfoxide (DMSO) were determined and found to be equivalent in both solvents. That is, use of reline as a solvent did not alter the functional properties of the metal complexes. Changes in the transdermal permeation of the complexes in DMSO and DES were assessed using a Franz diffusion cell. It was discovered that depending on the structure of the complex, the permeability might either increase (from 15 to 30%) or decrease (from 13 to 8%) with changes in the solvent, and this can be used to develop dosing strategies. Therapeutic eutectogels were successfully produced by impregnating SiO₂ nanoparticles with the metal complex solution in DES, facilitating convenient topical application.

Multifunctional hydrogels with an interpenetrated network structure have shown great potential for biomedical and tissue-regeneration applications. In this work, the biomedical hydrogel was fabricated with an interpenetrated network based on dopamine grafted gelatin (DA-Gel), and genipin crosslinked quaternary ammonium chitosan (QCS), incorporating epigallocatechin gallate (EGCG). The EDC/NHS and Schiff-base bond connections occurred in the hydrogels, as confirmed by Fourier-transform infrared (FT-IR) analysis. The properties of the fabricated hydrogels, including microstructure, degradation rate, adhesive strength, mechanical strength, and rheological behavior, can be regulated by adjusting the DA-Gel/QCS ratio or by using different crosslinking approaches. In addition, the fabricated hydrogels exhibited self-healing properties and strong adhesion to various materials and organs. Furthermore, the hydrogels performed good antibacterial activity against the typical bacteria, Escherichia coli and Staphylococcus aureus. EGCG encapsulated hydrogels displayed excellent antioxidant activities and good hemocompatibility. The hydrogels also demonstrated excellent cytocompatibility and good cell migration ability. The above results provide a facile approach to fabricate the biomedical hydrogels with a regulated network structure and multifunctional characteristics with potential in biomedical applications.

Hydrogels are three-dimensional hydrophilic network structures with one or more polymers cross-linked, with excellent biocompatibility, drug-carrying function, and biodegradability. Meanwhile, skin wound repair includes hemostasis and coagulation, an inflammation stage, a proliferation stage, and a remodeling stage. Therefore, hydrogels loaded with natural products are widely used in repairing skin wounds through various mechanisms such as hemostasis, antibacterial activity, anti-inflammatory activity, angiogenesis promotion, skin regeneration, and skin repair monitoring. In addition, this study provides the cross-linking mechanism (physical cross-linking and chemical cross-linking) and construction mode (self-assembly and physical parcels) of the loaded natural product hydrogel. In general, the purpose of this paper is to comprehensively understand the mechanism and preparation strategy of hydrogels loaded with natural products for skin repair and provide theoretical reference for future skin repair research.

Protein-based materials such as human serum albumin (HSA) have demonstrated significant potential for the development of novel wound management materials. For the first time, the formation of HSA-based hydrogels was proposed using a combination of thermal- and ethanol-induced approaches. The combination of phosphate-buffered saline (PBS) and limited (up to 20% v/v) ethanol content offers a promising strategy for fabricating human serum albumin-based hydrogels with tunable properties. The hydrogel formation was studied using in situ dynamic light scattering (DLS) for qualitative and semi-quantitative analysis of the patterns of protein hydrogel formation through thermally induced gelation. The rheological properties of human serum albumin-based hydrogels were investigated. Hydrogels synthesized via thermally induced gelation using a denaturing agent exhibit a dynamic viscosity ranging from 100 to 10,000 mPa·s. The biocompatibility, biodegradability, and structural stability of human serum albumin-based hydrogels were comprehensively evaluated in physiologically relevant media. These human serum albumin-based hydrogels represent a promising platform for developing topical therapeutic agents for wound management and tissue engineering applications. This study investigated the kinetics of tetracycline release from human serum albumin-based hydrogels in PBS and fetal bovine serum (FBS). All tested formulations of HSA-based hydrogels loaded with tetracycline (1 mg/mL) demonstrated antibacterial activity against Staphylococcus aureus, Staphylococcus epidermidis, Staphylococcus haemolyticus, and Corynebacterium striatum strains.

In this work, sodium alginate/chitosan (SA/CS) blend films were prepared by thermo-compression for the first time. Glycerol and lactic acid were used as de-structuring agents for SA and CS, respectively. The chemical structures, thermal stability, phase morphology, mechanical properties, water resistance, film opacity, film color, and soil burial test of thermo-compressed SA/CS films were investigated. The results indicate that intermolecular interactions in polyelectrolyte complexes in SA/CS blends were detected. Blending with CS improved the thermal stability of SA-based films. The SA/CS films showed excellent phase compatibility between SA and CS. The addition of CS improved the tensile properties of the SA-based films. The incorporation of CS in SA films resulted in enhanced water resistance and opacity and a decrease in biodegradability under soil burial. Thermo-compressed SA/CS films show promise for development and increased production capacity. These films can be tailored by varying the SA/CS ratios to display different properties. This versatility makes them suitable for a range of sustainable and diverse applications, including wound dressing, drug delivery, biosorbents, and packaging.

In the original publication [...].

Polysaccharide-based wound dressings face challenges in mechanical properties and effective wound repair for infected wound surfaces. This study presents a novel polyvinyl alcohol (PVA)/Salecan (Sal) composite hydrogel dressing with high toughness, biocompatibility, and wound healing capabilities, developed using an interpenetrating polymer network strategy. The primary network was formed through electrostatic interactions between polydopamine (PDA) and biocompatible polysaccharide Salecan, followed by incorporation of AgNO₃, which was in situ reduced to silver nanoparticles within the hydrogel. PVA was introduced as a secondary matrix, further reinforcing the hydrogel network through cyclic freeze-thawing. The resulting hydrogel exhibited a tensile strength of 0.31 MPa, an elongation at break of 158.9%, and a toughness of 31.16 J·m^-2, demonstrating enhanced mechanical performance compared to both Salecan/PDA and previously reported Salecan/Fe³⁺ hydrogel. Co-culture experiments showed the hydrogel's strong antibacterial effects, inhibiting 80.1% of Escherichia coli (E. coli) and 99.5% of Staphylococcus aureus (S. aureus). Fibroblast culture tests confirmed its excellent cytocompatibility. In vivo studies on infected wounds showed nearly complete healing in the S. aureus + hydrogel group within 12 days. Quantitative immunohistochemical analysis of CD31 revealed that hydrogel treatment significantly upregulated CD31 expression, indicating enhanced neovascularization. Complementary Western blot analysis further demonstrated that hydrogel-treated groups exhibited a marked downregulation of pro-inflammatory factors alongside CD31 upregulation. In summary, the PVA/Sal-based hydrogel represents a valuable strategy for reducing inflammation and promoting regeneration in the management of infected wounds.

Saliva substitutes are the standard treatment for dry mouth. This study aimed to evaluate the clinical effectiveness of a novel artificial saliva gel (RSU gel) compared with a commercial product (GC Dry Mouth Gel^®). A randomized, double-blind, two-phase crossover clinical trial was conducted with 37 participants with xerostomia. In the short-term phase, oral wetness, xerostomia scores, and clinical score of oral dryness (CSOD) were assessed up to 60 min after a single gel application. In the short-term repeated-use phase, each gel was applied 4 times daily for 14 days, separated by a 14-day washout period. The same parameters, including patient satisfaction and adverse events, were re-evaluated. Data were analyzed using generalized linear mixed models and generalized estimating equations. Both the RSU and GC Dry Mouth Gel^® significantly improved oral wetness immediately after a single application. No significant difference was observed for the RSU gel relative to the GC Dry Mouth Gel^® for oral wetness (OR = 1.01, 95% CI 0.98, 1.04, p = 0.248), xerostomia score (OR = 1.10, 95% CI 0.42, 2.88, p = 0.661), or CSOD (OR = 0.95, 95% CI 0.58, 1.55, p = 0.765) at 60 min. After 14 days of use, oral wetness increased significantly in both groups (2.94%, 95% CI 0.30%, 5.76%, p = 0.030) and did not differ significantly between the two products (p = 0.110). The xerostomia scores and CSOD also significantly improved, independent of product type (OR = 7.21, 95% CI 2.56, 20.34, p < 0.001, and OR = 2.82, 95% CI 1.50, 5.32, p = 0.001, respectively). The participants reported high satisfaction and acceptable taste, and no adverse effects were detected in those using the RSU gel throughout the study. Its lower cost and local availability make it a practical option for xerostomia management, particularly in populations with limited access to commercial saliva substitutes.

(1) Background: Gastroretentive systems are an interesting option for enhancing the bioavailability of weak bases and poorly soluble drugs. The aim of this study was to formulate supramolecular organogels based on cinnarizine (CIN) as a potential gastroretentive system. (2) Methods: The organogels were prepared with different oils in different ratios. Thereafter, their pharmaceutical characteristics and in vitro gastric retention were evaluated through in vitro and in silico simulations. (3) Results: Organogels with different proportions of CIN to oils were successfully obtained. The DSC thermal analysis results demonstrated that all organogels showed gel-sol temperature transitions. The frequency sweep test verified that all organogels presented frequency-independent behavior. Optical imaging revealed longitudinal spherulites of the 1:4 CIN in organogels in all oils. The CIN organogels in all oils (1:4) were observed to float in gastric media during the entire release study. The pharmacokinetic parameters of CIN in peppermint oil (1:4) revealed a close Cmax value to that of the 25 mg immediate-release tablet, but a different AUC. (4) Conclusions: The organogels in all oils floated throughout the release study, establishing their potential as a gastroretentive system. Furthermore, these dosage forms were assessed as a gastric-controlled system through in silico simulations, which enabled prediction of their pharmacokinetic parameters.