This study explores an innovative delivery strategy for the management of skin conditions: lipid nanosystems incorporated into a gel matrix. Echinacea purpurea extract, known for its antibacterial, antioxidant, and wound-healing properties, was encapsulated into lipid-based nanosystems and subsequently incorporated into Carbopol-based gel. The extract, rich in chicoric and caftaric acids, exhibited strong antioxidant activity (IC50 = 56.9 µg/mL). The resulting nanosystems showed nanometric size (about 200 nm), high entrapment efficiency (63.10–75.15%), and excellent short-term stability. Superior biocompatibility of the nanosystems, compared to the free extract, was demonstrated using an MTS assay on L-929 fibroblasts. Moreover, the cytoprotective potential of the lipid carriers was evident, as pre-treatment significantly increased cell viability under H2O2-induced oxidative stress. These findings suggest that lipid-based encapsulation enhances the therapeutic profile of E. purpurea. The optimal lipid formulation was incorporated into a Carbopol-based gel, which demonstrated an appropriate pH (5.15 ± 0.75), favorable textural properties, sustained polyphenol release, and overall good stability. This research highlights the potential of plant-derived bioactives in the development of dermatocosmetic products, aligning with current trends in eco-conscious and sustainable skincare.

Experimental measurement of dose distributions is a pivotal step in the quality assurance of radiotherapy treatments, especially for those relying on high delivery accuracy such as hadron therapy. This study investigated the response of a polymer gel dosimeter to determine its suitability in performing geometric beam characterizations for hadron therapy under high-quenching conditions. Different extraction energies of proton and carbon ion beams were considered. Gel dose–response linearity and long-term stability were confirmed through optical measurements. Gel phantoms were irradiated with pencil beams and analyzed via magnetic resonance imaging. A multi-echo T2-weighted sequence was used to reconstruct depth–dose profiles and transversal distributions acquired by the gels, which were benchmarked against reference data. As expected, a response-quenching effect in the Bragg peak region was noted. Nonetheless, the studied gel formulation proved reliable in acquiring the geometric characteristics of the beams, even without correcting for the quenching effect. Indeed, depth–dose distributions acquired by the gels showed an excellent agreement with measured particle range with respect to reference values, with mean discrepancies of 0.5 ± 0.2 mm. Single-spot transverse FWHM values at increasing depths also presented an average agreement within 1 mm with values determined with radiochromic films, thus supporting the excellent spatial resolving capabilities of the dosimetric gel.

Hydrogels comprise three-dimensional networks of hydrophilic polymers and have attracted considerable interest in various sectors, including the biomedical, pharmaceutical, agricultural, and food industries. These materials offer significant benefits for food packaging applications, such as high mechanical strength and excellent water absorption capacity, thereby contributing to the extension of product shelf life. Therefore, the aim of this study is to compare the performance of citric acid and glutaraldehyde as crosslinking agents in gelatine-based hydrogels reinforced with cellulose nanocrystals (CNC), contributing to the development of safe and environmentally responsible materials. The hydrogels were prepared using the casting method and characterised in terms of their physical, mechanical, and structural properties. The results indicated that hydrogels crosslinked with glutaraldehyde exhibited higher opacity, lower transparency, and greater mechanical strength, whereas those crosslinked with citric acid demonstrated improved clarity, reduced water permeability, and enhanced swelling capacity. The incorporation of CNC further improved mechanical strength, reduced weight loss, and altered both surface homogeneity and optical properties. Microstructural results obtained by SEM were consistent with the mechanical properties evaluated (TS, %E, and EM). The Gel-ca hydrogel displayed the highest elongation value (98%), reflecting better cohesion within the polymeric matrix. In contrast, films incorporating CNC exhibited greater roughness and cracking, which correlated with increased rigidity and mechanical strength, as evidenced by the high Young’s modulus (420 MPa in Gel-ga-CNC2). These findings suggest that the heterogeneity and porosity induced by CNC limit the mobility of polymer chains, resulting in less flexible and more rigid structures. Additionally, the DSC analysis revealed that gelatine hydrogels did not exhibit a well-defined Tg, due to the predominance of crystalline domains. Systems crosslinked with citric acid showed greater thermal stability (higher Tm and ΔHm values), while those crosslinked with glutaraldehyde, although mechanically stronger, exhibited lower thermal stability. These results confirm the decisive effect of the crosslinking agent and CNC incorporation on the structural and thermal behaviour of hydrogels. In this context, the application of hydrogels in packaged products represents an eco-friendly alternative that enhances product presentation. This research supports the reduction in plastic consumption whilst promoting the principles of a circular economy and facilitating the development of materials with lower environmental impact.

Chitosan is a promising biopolymer for drug delivery due to its biocompatibility, biodegradability, and low toxicity. However, its limited dispersibility in water restricts applications, which can be improved through organic acid salts. This study examined how acetic, lactic, glutamic, and citric acids influence the physicochemical, rheological, swelling, bioadhesive, stability, and cytotoxicity properties of chitosan hydrogels. Gels were prepared using varying chitosan-to-acid molar ratios (1:1; 1:1.2 for citrate) and characterized by NMR, FTIR, TGA, and XRD. Despite identical chitosan concentrations (2%, 3%, 3.5%), gels displayed distinct viscosity, swelling, and adhesion profiles depending on the acid. Lactate gels exhibited the most favorable overall performance, combining high viscosity (1555–6665 mPa·s), structural stability, and strong bioadhesion. Citrate gels showed the lowest viscosity (825–3550 mPa·s), cell viability, and stability but the highest bioadhesiveness, likely due to multivalent ionic interactions. Short-term stability tests revealed that low pH accelerated chitosan degradation, leading to viscosity loss up to ~90–95% within 30 days, particularly in citrate hydrogels. Cytotoxicity tests confirmed high biocompatibility, with all formulations maintaining cell viability above 80%. Overall, the findings highlight that organic acid selection is a critical determinant of chitosan gel behavior, offering guidance for tailoring safe, stable, and bioadhesive drug delivery systems.

Antibodies are indispensable for protection against biological toxins and pathogens, yet their conventional liquid formulations impose severe constraints, including dosing inaccuracy caused by residual fluid remaining in the syringe and limited user convenience such as pain caused by fluid-induced tissue distension and nerve stimulation as well as instability in ambient temperature, and the requirement for low-temperature storage and logistics. These limitations critically impair rapid deployment during golden hour following acute exposure. Here, we report an antibody-integrated solid-to-gel microfilm—demonstrated with a 100 µg anti-BoNT/A dose—jet-printed and low-temperature dried directly onto metal needles for consistent, on-demand use. Upon intradermal insertion, the microfilm fully dissolves within 5 min, driven by hydration-induced swelling of a hyaluronic acid (HA) support layer and rapid release of the antibody. Time-resolved microscopy and UV–vis analysis showed a decrease in residual solid from 2.34 mm3 to 0 over 300 s, with a concomitant rise at 187 nm indicative of complete dissolution. The solid formulation maintained ambient-temperature stability for 3–6 months with pharmacokinetics comparable to conventional subcutaneous liquid injections. In a lethal BoNT/A challenge, treated mice achieved 100% survival for 12 days, whereas controls succumbed within 16 h.

Hybrid polysaccharide-based aerogels offer significant potential as advanced drug delivery platforms due to their tunable structure, high porosity, and biocompatibility. In this study, aerogel microparticles were synthesized using alginate, pectin, carrageenan, and their hybrid formulations via an emulsion–gelation technique followed by supercritical fluid CO2 extraction. The resulting aerogels exhibit mesoporous structures with specific surface areas ranging from 324 to 521 m2/g and pore volumes between 1.99 and 3.75 cm3/g. Comprehensive characterization (SEM, gas sorption, XRD, TGA, DSC, and FTIR) confirmed that hybridization improved morphological uniformity and thermal stability compared to single polymer aerogels. Ibuprofen was used as a model drug to evaluate loading efficiency and release kinetics. Among all formulations, the alginate/carrageenan (2:1) hybrid showed the highest drug loading efficiency (93.5%) and a rapid release profile (>90% within 15 min), closely matching the performance of commercial ibuprofen tablets. Drug release followed Fickian diffusion, as confirmed by the Korsmeyer–Peppas model (R2 > 0.99). These results highlight the potential of hybrid polysaccharide aerogels as vehicles for drug delivery and other fast-acting therapeutic applications.

Battery technology represents a cornerstone in the evolution of the energy sector, driven by the urgent need for sustainable and efficient energy storage systems. Various materials, including metals, non-metals, semiconductors, and polymeric gel conductors comprise batteries, and their size and composition can significantly affect battery performance. The essential components of a battery are electrolytes, electrodes, nanogelators, and membranes that can be built up by using nanogels. The nanogel components significantly enhance the efficiency and stability of redox-active flow batteries, which makes them cheaper and eco-friendly. Little research has been conducted on nanogel-based battery technology. This study mainly focuses on the nanogels used in the components of batteries. The review explains the functions of nanogels in different electrolytes, electrodes, nanogelators, and membranes. This review explicitly discusses the current status and literature background of nanogels and hydrogels in battery technology. For anyone interested in delving deeper into the realm of nanogel-based batteries, this review article serves as a valuable resource, offering a thorough exploration of their role in revolutionizing modern energy storage systems.

Soft tissues exhibit remarkable stretchability, fracture toughness, and stress–relaxation ability. They possess a large water content to support cellular processes. Mimicking such a combination of mechanical and physical properties in hydrogels is important for tissue engineering applications but remains challenging. This work aims to develop a hydrogel that can combine excellent mechanical properties with cellular viability. The research focused on polyvinyl alcohol (PVA)/agar double-network (DN) hydrogels, fabricated by thermal gelation and freeze–thawing methods. Their mechanical properties were characterized through tension, compression, fracture, and stress–relaxation tests, and their cellular viability was measured through cytotoxicity tests. The results show that the PVA/agar DN gels are highly stretchable (>200%) and compressible (>30%) while containing high water content. The incorporation of agar by 6 wt% improved the fracture toughness of hydrogels from 1 to 1.76 kJ/m2. The degree of stress–relaxation, a key indicator of gel viscoelastic properties, improved by roughly 170% with an increase in agar content from 0 to 6 wt%. Cytotoxicity analysis showed that the gels, being physically cross-linked, were able to promote cellular proliferation. This work shows that tough and viscoelastic PVA/agar DN gels are suitable for soft tissue engineering applications, especially cartilage repair.

In this study, a flexible hydrogel film sensor based on the intermixing of poly(vinyl alcohol) (PVA) and biomass-derived carbon nanoparticles (CNPs) was prepared and microstructures were constructed by replicating sandpaper templates on its surface. The sensor thus has good overall sensing performance with a sensitivity of 101 kPa−1, a fast response/recovery time of 22 ms and 20,000 fatigue cycles. The sensor was experimentally verified to accurately capture human joint movements, current signals of written letters, and weight differences in the size of spherical objects. Based on this, a breathing phase classification framework was constructed using the 1D-CNN algorithm, achieving a synergistic enhancement effect between environmentally scalable materials and Deep learning algorithms. This approach not only improves the signal discrimination function, but also provides new ideas for wearable medical monitoring, haptic feedback and intelligent robot human–machine interface.

Accurate thermal characterization of closed mesoporous metal gels is vital for high-temperature uses, yet microscale effects often ignored in macroscopic models significantly impact heat transfer. This study introduces a new predictive method based on an equivalent Voronoi model, accounting for the Knudsen effect and microscale electromagnetic interactions. Predicted thermal conductivity closely matched experimental results, with an average error of 5.35%. The results demonstrate that thermal conductivity decreases with porosity, increases with temperature, and varies with pore size, with a minimum of 17.47 W/(m·K) observed at ~1 μm. Variations in refractive index, extinction coefficient, and specific surface area exert negligible influence. Conductive heat transfer is suppressed under Knudsen-dominated conditions at small pore sizes. Electromagnetic analysis around the pore size corresponding to minimum conductivity reveals localized surface plasmon resonances and magnetic coupling at the gas–solid interface, which enhance radiative dissipation and further reduce thermal conductivity. Radiation dissipation efficiency increases with decreasing porosity and pore size. This model thus serves as a predictive tool for designing high-performance thermal insulation systems for elevated-temperature applications.