Gels最新文献

Altrenogest is a key regulatory hormone for intensive and batch management of reserve sows in breeding farms. As a synthetic hormone, altrenogest could make ovaries stay at the initial stage of follicles and inhibit estrus and ovulation in animals. However, the currently used oral altrenogest solution needs to be administered continuously every day for more than two weeks in clinical practice. In this study we developed a phospholipid-based injectable gel carrying altrenogest to decrease the number of administrations, sustain release of the drug, and enhance therapeutic efficacy for clinical use. The altrenogest gel had a viscosity of 100 cP before phase transition and over 1,000,000 cP after phase transition. In vitro, altrenogest can be continuously released from gel for over two weeks. The pharmacokinetic results showed that the AUC _(0-∞) of the altrenogest gel was almost double that of the altrenogest solution. The MRT _(0-∞) was 40.92 ± 7.21 h and the t_1/2 of the altrenogest gel was 80.03 ± 20.79 h. The altrenogest gel demonstrated excellent fluidity, ease of injectability, high drug-loading capacity, and appropriate sustained-release characteristics both in vitro and in vivo, making it a potential drug delivery system for swine production.

The local application of broad-spectrum antibiotics via polymeric drug delivery systems is a promising alternative to their systemic administration in wound healing, prevention and treatment of infections associated with surgical implants. However, low and poorly controlled loading efficiency and 100% burst release are common problems for the materials with weak physical interaction between antibiotics and polymeric matrices. Here, we report a new multifunctional carboxymethyl chitosan (CMC) cryogel, which efficiently prevents bacterial adhesion to the surface, kills bacteria in the solution via controlled release of ciprofloxacin (CIP), and promotes fibroblast proliferation. The suggested approach is based on CIP loading to Zn²⁺-chelated CMC cryogel via the ligand exchange reaction. We have shown that, due to the strong binding of Zn²⁺ to CMC, the antibacterial effect and toxicity to fibroblasts of CMC-Zn-CIP cryogels were mainly determined by the content of loaded CIP, which can be precisely controlled via Zn²⁺ content in cryogel. CMC cryogels containing 20 mgZn/g can be loaded with CIP amounts sufficient to completely suppress the growth of hospital strain Klebsiella oxytoca with MIC of 0.125 µg/mL, while maintaining a fibroblast viability at the level of 85-90%.

Chronic wounds represent a persistent clinical challenge due to prolonged inflammation and impaired tissue repair mechanisms. Cannabidiol (CBD), recognized for its anti-inflammatory and pro-healing properties, shows therapeutic promise in wound care. However, its delivery via lipid nanoparticles (LNPs) remains challenging due to CBD's inherent instability and low bioavailability. This study developed and characterized a novel hydrogel scaffold composed of CBD-loaded LNPs (CBD/LNPs) integrated into a polyvinyl alcohol (PVA) and sodium alginate (SA) matrix, designed to enhance wound repair and mitigate inflammation. The characteristics of the hydrogel scaffold were observed including the degree of swelling and LNPs' release profiles. Furthermore, in the results, CBD/LNPs displayed enhanced stability and reduced cytotoxicity compared to unencapsulated CBD. In vitro assays demonstrated that CBD/LNPs significantly promoted fibroblast migration in gap-closure wound models and reduced intracellular reactive oxygen species, supporting their potential as a biocompatible and efficacious agent for cellular repair and oxidative stress attenuation. In vivo experiments using adult male Wistar rats with aseptic cutaneous wounds revealed that treatment with CBD/LNP-PVA/SA hydrogel scaffold significantly accelerated wound closure relative to blank hydrogel controls, demonstrating a substantial reduction in the wound area over time. Histological analysis confirms notable improvements in skin morphology in wounds treated with CBD/LNP-PVA/SA hydrogel scaffold with evidence of accelerated epithelialization, enhanced collagen deposition, and increased dermal thickness and vascularization. Additionally, skin histology showed a more organized epidermal layer and reduced inflammatory cell infiltration in CBD/LNP-PVA/SA hydrogel scaffold-treated wounds, corresponding to a 35% increase in the wound closure rate by day 28 post-treatment. These findings suggest that CBD/LNP-PVA/SA hydrogel scaffolds facilitate inflammation resolution and structural wound healing through localized, sustained CBD delivery. The dual anti-inflammatory and wound-healing effects position CBD/LNP-PVA/SA hydrogel scaffold as a promising approach for chronic wound management. Future investigations are warranted to elucidate the mechanistic pathways by which CBD modulates the skin architecture and to explore its translational applications in clinical wound care.

This research enhances the thermal safety of hydrophobic silica aerogel (HSA) by integrating layered double oxides (LDOs). XRD and FTIR confirm that the introduction of LDOs does not affect the formation of SA. The LDO/SA composites demonstrate a low density (0.14-0.16 g/cm³), low thermal conductivity (23.28-28.72 mW/(m·K)), high porosity (93.4-96.1%), and a high surface area (899.2-1006.4 m²/g). The TG-DSC results reveal that LDO/SA shows enhanced thermal stability, with increases of 49 °C in the decomposition onset temperature and 47.4 °C in the peak decomposition temperature. The gross calorific value of LDO/SA-15% (with 15 wt% LDO) exhibits a 23.9% reduction in comparison to that of pure SA. The decrease in gross calorific value, along with improved thermal stability, indicates a boost in the thermal safety characteristics of the LDO/SA composites. This study demonstrates that incorporating LDOs enhances the thermal safety of HSA, while preserving its superior performance, thus broadening its potential applications in thermal insulation.

This paper provides a solid foundation for understanding the synthesis, properties, and applications of cellulose-based gels. It effectively showcases the potential of these gels in diverse applications, particularly in biomedicine, and highlights key synthesis methods and properties. However, to push the field forward, future research should address the gaps in understanding the environmental impact, mechanical stability, and scalability of cellulose-based gels, while also considering how to overcome barriers to their industrial use. This will ultimately allow for the realization of cellulose-based gels in large-scale, sustainable applications.

Currently, materials with specific, strictly defined functional properties are becoming increasingly important. A promising strategy for achieving these properties involves developing methods that facilitate the formation of hierarchical porous materials that combine micro-, meso-, and macropores in their structure. Macropores facilitate effective mass transfer of substances to the meso- and micropores, where further adsorption or reaction processes can occur. Aerogels represent a promising class of materials for implementing this approach. The formation of hierarchical porous structures in aerogels can be achieved using soft and hard templating methods or by foaming techniques. This paper presents a comprehensive study of three methods for forming hierarchical porous structures in alginate aerogels: (1) employing surfactants (Pluronic F-68), (2) using zein as a pore-forming component, and (3) foaming in a carbon dioxide medium. The results of micro-CT showed that each of the methods contributes to the formation of macropores within the structure of the resulting aerogels. Size distribution curves of the detected macropores were obtained, showing the presence of macropores ranging from 16 to 323 μm in size for samples obtained using surfactants, from 5 to 195 μm for samples obtained using zein, and from 20 μm to 3 mm for samples obtained by foaming in a carbon dioxide medium. The SEM images demonstrated the macro- and mesoporous fibrous structure of the obtained materials. The nitrogen porosimetry results indicated that samples obtained using surfactants and zein are characterized by a high specific surface area (592-673 m²/g), comparable to the specific surface area for an alginate-based aerogel obtained without the use of pore-forming components. However, the use of the developed methods for the formation of a hierarchical porous structure contributes to an increase in the specific mesopores volume (up to 17.7 cm³/g). The materials obtained by foaming in a carbon dioxide medium are characterized by lower specific surface areas (112-239 m²/g) and specific mesopores volumes (0.6-2.1 cm³/g). Thus, this paper presents a set of methods for forming hierarchical porous structures that can obtain delivery systems for active substances with a controlled release profile and highly efficient platforms for cell culturing.

Buccal drug delivery offers a promising alternative for avoiding gastrointestinal degradation and first-pass metabolism. However, enhancing the buccal epithelial barrier's permeability remains challenging. This study explores the effects of ethanolic extracts from Citrus medica var. Balady (CM), Citrus medica var. Calabria (CMC), and Origanum dayi (ORD) on buccal epithelium permeability in vitro using a TR146 cell-based model. The cell viability assay revealed that the extracts were non-toxic at the concentration range tested (<0.5% w/v). Surprisingly, none of the tested extracts significantly enhanced the buccal permeability of 40 kDa Fluorescein Isothiocyanate Dextran (FD40). However, the CMC and ORD extracts significantly reduced the epithelial permeability of FD40, mirroring the effects of hyaluronic acid (HA), a known barrier integrity enhancer. The total phenolic content (TPC) analysis suggested a potential link between the phenolic concentration and epithelial barrier reinforcement. The rapid colorimetric response method was applied to assess the interaction of these extracts with biological membranes. The results indicated that HA interacts with cellular membranes via lipid bilayer penetration, whereas the extracts likely influence the barrier integrity through alternative mechanisms, such as ligand-receptor interactions or extracellular matrix modulation. These findings highlight the potential of CMC and ORD extracts as natural agents to enhance buccal epithelial integrity. In conclusion, incorporating these extracts into formulations, such as hydrogels, could offer a cost-effective and biocompatible alternative to HA for improving buccal cavity health.

The objective of this work was to develop a supersaturated gel formulation (SGF) loaded with the maximum atorvastatin calcium trihydrate (ATR) dose. The maximum dose strength of ATR needs to be reduced through improving solubility and dissolution rate to mitigate side effects due to the necessity of taking high doses. ATR has highly pH-dependent solubility at 37 °C, leading to poor solubility (<10 μg/mL) in stomach acid (pH 1.2). Among the various molecular weights of polyethylene glycols (PEGs) and surfactants, PEG 200 and d-α-tocopheryl polyethylene glycol 1000 succinate (TPGS) were selected as the solubilizer and precipitation inhibitor for ATR, respectively. PEG 200 demonstrated very high solubility for ATR (>60%, w/w), and the combined use of TPGS and PEG 200 formed an organogel state and suppressed ATR precipitation, showing 15-fold higher dispersion solubility in buffer solution at pH 1.2 compared to the formulation with PEG 200 alone. The optimal SGF composition (ATR/PEG 200/TPGS = 10/60/30, w/w) exhibited an over 95% dissolution rate within 2 h at pH 1.2, compared to less than 50% for the original commercial product. In a transmission electron microscope analysis, the SGF suppressed ATR precipitation and revealed smaller precipitated particles (<300 nm) compared to the control samples. In the XRD analysis, the SGF was physically stable for 100 days at room temperature without the recrystallization of ATR. In conclusion, the SGF suggested in this work would be an alternative formulation for the treatment of dyslipidemia with enhanced solubility, dissolution, and physical stability.

The study aimed to prepare complex gels of sonicated quinoa protein (QP) and polysaccharides, comparing the effects of different protein components and pH on gel properties. FTIR analysis demonstrated that the β-structure in protein at pH 7.0 was enhanced by ultrasonic treatment, which could promote the formation of a gel network. Moreover, XG-AG (gel prepared by xanthan gum and albumin) and XG-GG (gel prepared by xanthan gum and globulin) exhibited higher levels of disulfide bonds and free sulfhydryl groups in the gel, requiring more energy to break the intermolecular sulfide bonds during heating. Under the same heating conditions, the rheological properties and gel strength of XG-UQPG (gel prepared by xanthan gum and ultrasonically treated QP) were superior to those of XG-UGG (gel prepared by xanthan gum and ultrasonically treated globulin) and XG-UAG (gel prepared by xanthan gum and ultrasonically treated albumin). Additionally, XG-UGG (pH 7.0) demonstrated the highest water holding capacity (WHC) and oil holding capacity (OHC). This was attributed to the disulfide bonds created in the proteins by the ultrasound treatment, encouraging them to interact to form more uniform holes in gel that can hold more water/oil molecules. Conversely, at pH 4.5, the WHCs of the gels were reduced due to the presence of rougher protein structures. These findings shed light on the impact of protein composition on gel properties and offer insights into enhancing the quality of quinoa protein gel.