Search Results (8,652)

Biodegradable polymers such as Polycaprolactone (PCL), Polylactic acid (PLA), and Poly(lactic-co-glycolic acid) (PLGA) are attracting attention as key platforms for anticancer drug delivery systems due to their excellent biocompatibility and controllable degradation rates. These polymers can overcome limitations of existing chemotherapeutics, such as low bioavailability, systemic toxicity, and nonspecific cell damage, and contribute to the development of precision medicine approaches and long-acting therapeutics. This paper discusses the chemical and physicochemical properties of these three polymers, their synthetic strategies, and the controlled drug release technology through surface functionalization and stimuli-responsive design. Furthermore, we highlight their potential for use in various formulations, including micelles, nanoparticles, hydrogels, and microspheres, enabling enhanced drug solubility, sustained release, and tumor targeting. Preclinical and clinical applications demonstrate that these polymer-based DDSs represent a promising approach for implementing next-generation precision anticancer treatment strategies, with further potential for clinical translation and widespread adoption. Full article

Background/Objectives: Glioblastoma (GBM) is a fatal tumor in the central nervous system (CNS) with a poor prognosis. Preventing tumors from post-surgical recurrence is a significant clinical challenge, since current methods deliver chemotherapeutic agents in a rapid manner and are not effective against the residual tumor cells. To address these limitations, we develop a blue light-crosslinking hydrogel which can be rapidly gelled in situ and tightly adhere on the tissues for controlled chemotherapy, radiotherapy, and enhanced laser interstitial thermal therapy (LITT) to inhibit residual tumor cells from post-surgical recurrence. Methods: We utilize gelatin-MA based hydrogel with crosslinker VA-086 as hydrogel scaffold to encapsulate small-molecule drugs (Epirubicin and Cisplatin) and LITT agent polypyrrole-coated graphine oxide (PPy@GO). The mixture can form into hydrogel in situ by blue light irradiation and performed chemo-LITT and radio therapy simultaneously. Then we determine the prevailing factors that affect efficient encapsulation of therapeutic agents within hydrogels, efficiency of gelation, LITT enhancement, and drug release. Then evaluate efficiency in human cancer cells and an in vivo tumor model. Results: Our results demonstrate that 18 wt% Gelatin MA formulation achieved >95% gelation within 2 min, with drug-loaded gels forming within 5 min. The gelation can perform both in vitro and in vivo without affect the drug efficiency. This multi-treatment system can effectively prevent tumor recurrence and significantly prolong the medium survival of glioma-bearing (MBR-614 or U87-MGFL) mice to above 65 days compared with the control group (36 days). Conclusions: The results demonstrated promising effect of this system as a multi-therapeutic platform which combined chemo-LITT and RT. This synergistic strategy presents a new approach to the development of a local drug delivery system for the prevention of brain tumor recurrence. Full article

The rational design of advanced composite gels requires rigorous rheological analysis to decode their flow-deformation mechanisms, a prerequisite for optimizing performance in food and biomedical applications. However, systematic thermal analysis and rheological profiling of Salecan/Sanxan hydrogels remain unexplored, constituting a critical knowledge gap in this field. This study engineered Salecan/Sanxan hydrogels and systematically probed Salecan-dependent rheological and thermal properties. Through Power Law and Herschel–Bulkley model analyses, the hydrogels demonstrated composition-dependent rheological properties: yield stress (4.7–29.2 Pa), η₅₀ (342.6–3011.4 mPa·s), and Arrhenius equation fitting revealed tunable activation energy (14,688.3–30,997.1 J·mol⁻¹). Notably, when the gel was formulated with 3% Sanxan and 2% Salecan at a volume ratio of 1:2, its thermal-decomposition temperature rose by 9%, from 224.4 °C to 245.1 °C. Conversely, a 1:1 mixture of 2% Sanxan and 2% Salecan produced the lowest freezing point recorded (–18.3 °C), an 18% reduction compared with the control (–15.4 °C). These findings demonstrate the tunable rheological and thermal properties of Salecan/Sanxan hydrogels. By establishing that precise modulation of polymer mixing ratios can match the entire processing shear spectrum, this study not only fills a critical knowledge gap but also creates a versatile platform for designing tailor-made foods and biomedical matrices. Full article

Background: Dysphagia is a common problem in older adults, characterized as a swallowing disorder that prevents food from passing from the mouth to the esophagus. Besides impairing dietary intake and leading to malnutrition, dysphagia also severely restricts water intake. Purpose: This study aimed to develop polysaccharide-based hydrogels as dysphagia-friendly finger foods designed to provide high water content and enable controlled vitamin delivery to older persons with dysphagia. Procedures: Agar–carboxymethylcellulose (Agar-CMC) composite hydrogels with incorporated vitamins C, B₉, B, and D₃ were developed and tested for their textural and rheological properties, vitamin stability during storage, and vitamin release under simulated gastrointestinal conditions. Finally, a fiberoptic endoscopic swallowing assessment and sensory evaluation were conducted. Main Findings: Increasing the agar concentration in Agar-CMC hydrogels improved their internal structure and handling properties as finger foods, while still being easily breakable during swallowing. Agar-CMC hydrogels’ structure protected vitamins during processing and six weeks of storage. Vitamin release started immediately and remained steady in the gastric phase, with a noticeable increase at the beginning of the intestinal phase, resulting in 70–100% vitamin release by the end of this phase. The Fiberoptic Endoscopic Swallowing Evaluation confirmed their suitability for individuals with mild to moderate oropharyngeal dysphagia, with a low risk of aspiration (1 point on the Penetration-Aspiration Scale out of 8). Principal Conclusions: The developed Agar-CMC hydrogels present a promising dysphagia-friendly finger food alternative with high water content. They effectively deliver essential vitamins throughout the gastrointestinal tract, and notably demonstrate a low aspiration risk, making them suitable for individuals with mild to moderate oropharyngeal dysphagia. Full article

Electroencephalography (EEG) electrodes require low impedance, high biocompatibility, and long-term performance. Conventional Ag/AgCl wet electrodes achieve low impedance but suffer from dehydration and skin irritation, whereas dry electrodes often induce discomfort or exhibit high impedance. To address these limitations, this study engineered a hydrogel-based electrode by incorporating PEDOT:PSS and the nonionic surfactant Triton X-100 into an acrylic acid hydrogel matrix. The flexible acrylic acid backbone, conductive PEDOT:PSS domains, and the nanofibrillar network promoted by Triton X-100 simultaneously enhanced mechanical compliance and electrical stability. In addition, the structural rearrangement of PEDOT:PSS was verified through morphological analyses. The fabricated electrode exhibited a modulus comparable to human soft tissue, demonstrated strong interfacial adhesion in shear tests, and significantly reduced skin–electrode contact impedance. Furthermore, EEG measurements showed that the hydrogel electrode achieved alpha- and beta-band signal power comparable to commercial Ag/AgCl electrodes. These findings establish the PEDOT:PSS–Triton X-100 hydrogel electrode as a promising candidate to replace conventional wet and dry electrodes for reliable EEG applications. Full article

Hydrogels based on poly (methacrylic acid), carboxymethyl cellulose, and nanocellulose fibers were successfully synthesized, characterized, and tested as topical carriers for the controlled release of hydrophobic resveratrol and hydrophilic acetyl glucosamine, active substances used in skin protection. Carrier composition was confirmed by Fourier-transform infrared spectroscopy (FTIR). Scanning electron microscopy (SEM) revealed the pore size variations with alterations in the neutralization degree of methacrylic acid and changes in the pore-wall roughness caused by different mass fractions of nanocellulose. The neutralization degree of methacrylic acid had a substantial impact on the swelling behaviour, while only a slight change in swelling was caused by various contents of nanocellulose in hydrogels. Mechanical properties of the hydrogels accessed by compressive strength measurement at various percentages of strain were improved by the addition of nanocellulose. Hydrogels containing 0.5% nanocellulose achieved the highest compressive strength. The neutralization of methacrylic acid reduced the mechanical properties. Hydrogels with optimal properties showed outstanding potential in encapsulation, and controlled the simultaneous release of resveratrol and N-acetyl glucosamine. The different nature of the active compounds, however, affected the release kinetics and mechanism, as confirmed by the Korsmeyer–Peppas model. Full article

Hydroxyapatite (HA) coatings improve implant bioactivity but suffer from brittleness and limited functionality. Here, we report a hybrid coating strategy combining flame-sprayed HA/TiO₂ with in situ hydrogel growth. TiO₂ incorporated into the HA matrix acted as a photocatalytic initiator for acrylamide polymerization under UV. Unlike conventional hydrogel coatings that require added photoinitiators or separate surface modification steps, TiO₂ incorporated into the HA layer serves as a built-in photocatalytic initiator, enabling direct polymerization of acrylamide monomers on the sprayed surface. The resulting HA/TiO₂–hydrogel coatings exhibited a continuous hydrogel layer with intimate contact to the ceramic surface, as evidenced by SEM cross-sections and elemental mapping. The HA/TiO₂ 1% coating produced a continuous coverage in close contact with the surface, while excessive TiO₂(5%) led to uncontrolled hydrogel growth and partial coating failure. SEM cross-sections revealed a dense, well-adhered coating with homogeneously distributed Ca, P, O, and finely dispersed Ti. Upon immersion in simulated body fluid (SBF), submicron globular deposits progressively developed on the coating surface. EDS showed an increase in Ca/P ratio from ~1.66 (as-sprayed) to ~1.92 (14 days). These findings highlight a straightforward approach for combining flame-sprayed ceramics with photocatalytic hydrogel growth, providing a practical route toward multifunctional implant surface modification. Full article

This study reports the use of an in situ-forming gel based on hyaluronic–chitosan–glycerophosphate for wound healing. Hydrogels with optimized thermoresponsive gelling, rheological, and prolonged drug release properties were developed and incorporated with ciprofloxacin and carvacrol. In vitro evaluations included rheological studies, swelling degree, degradation rates, morphological analysis, antioxidant effects, antimicrobial activity, and drug release studies. The effectiveness of the optimized hydrogel was assessed using an animal ischemic wound rabbit ear model. The incorporation of ciprofloxacin and carvacrol into the combined hydrogel system maintained the mechanical strength of the formula, with a G′/G″ ≈ ratio of approximately 15.6, interconnected porosity, and controlled swelling. It enhanced antimicrobial activity against both S. aureus and E. coli. In addition, the developed gel exhibited sustained release following the Higuchi diffusion kinetics. The quantitative wound area% indicated that on day 9, the mean wound area decreased from 81.8% for the control to 51.2% for the developed gel. The study findings demonstrate the suitability and potential of this system as multifunctional wound-healing formulations that promote moist healing, antimicrobial and antioxidant activities, while providing sustained therapeutic delivery over 24 h. Full article

Second-degree burns are common dermal injuries requiring effective interventions to promote timely and complete skin regeneration. This study evaluated the wound-healing efficacy of topical hydrogels containing powdered licorice root (Glycyrrhiza glabra L.) extract at concentrations of 5%, 10%, and 20% w/w in a standardized murine model. Female SKH-hrHR2 hairless mice (n = 8 per group) were subjected to second-degree thermal burns, and treatment hydrogel formulations were applied once daily under occlusive dressings. Wound healing was assessed by planimetric area measurements, transepidermal water loss (TEWL), and histopathology. By Day 19, complete wound closure was achieved in 87.5% of animals in the 5% group, compared with 50.0% in the 10% group, 37.5% in the 20% group, and 25.0% in the sodium alginate control (Fisher’s exact test, p = 0.008). TEWL remained unchanged in the 5% group (baseline vs. Day 19: 8.4 ± 1.2 vs. 8.6 ± 1.3 g/m²/h; p > 0.05) but increased significantly in all other groups (e.g., sodium alginate: 8.2 ± 1.1 to 13.5 ± 2.0 g/m²/h; p = 0.0001). Histologically, the 5% formulation showed near-normal epidermal architecture and minimal inflammation (mean total score 2.0) compared with higher concentrations (6.0 for 10% and 7.3 for 20%) and sodium alginate (8.3). These findings demonstrate that a 5% Glycyrrhiza glabra hydrogel provides, among the concentrations studied here, the most favorable balance of wound closure, barrier restoration, and histological recovery, supporting its further development as a topical therapy for second-degree burns. Full article

Aqueous zinc-ion batteries (ZIBs) have attracted growing interest as promising candidates for large-scale and flexible energy storage due to their intrinsic safety, low cost, and environmental sustainability. However, several persistent issues—such as uncontrolled Zn dendrite growth, hydrogen evolution-induced anode corrosion, and cathode dissolution—continue to hinder their commercial deployment. To address these challenges, hydrogel polymer electrolytes (HPEs) have emerged as an effective strategy. Their unique three-dimensional polymer networks not only retain water and confine ion transport, but also provide a solid–liquid hybrid environment that enhances ionic conductivity and interfacial compatibility. These features enable HPEs to suppress side reactions and improve both electrochemical stability and mechanical adaptability, which are especially valuable for flexible ZIB devices. This review first summarizes fundamental energy storage mechanisms in aqueous ZIBs, including reversible Zn²⁺ insertion/extraction, proton co-insertion, and cathode phase evolution. It then highlights recent progress in HPE design, with emphasis on polyacrylamide (PAM), polyvinyl alcohol (PVA), and polyacrylic acid (PAA)-based systems, with strategies for dendrite suppression, interfacial regulation, and mechanical robustness. Finally, current challenges and future directions are discussed, with a forward-looking perspective on scalable fabrication methods, advanced electrolyte design, and deeper mechanistic understanding necessary to fully realize the potential of HPE-enabled aqueous ZIBs. Full article

The demand for organ transplantation continues to rise worldwide, intensifying the gap between supply and demand and driving research in tissue engineering (TE). Bioprinting, particularly light-based vat photopolymerization (VP) methods such as digital light processing (DLP), has emerged as a promising strategy to fabricate complex, cell-compatible tissue constructs with high precision. In this study, we developed an open-source, bottom-up DLP bioprinter designed to provide a cost-effective and modular alternative to commercial systems. The device was built from commercially available components and custom-fabricated parts, with tolerance allocation and deviation analyses applied to ensure structural reliability. Mechanical and optical subsystems were modeled and validated, and the control architecture was implemented on the Arduino platform with a custom Python-based graphical interface. The system achieved a theoretical Z-axis resolution of 1 $\mathsf{\mu }$m and a vertical travel range of 50 mm, with accuracy and repeatability comparable to research-grade bioprinters. Initial printing trials using polyethylene glycol diacrylate (PEGDA) hydrogels demonstrated high-fidelity microfluidic constructs with adequate dimensional precision. Collectively, these results validate the functionality of the proposed system and highlight its potential as a flexible, precise, and cost-effective platform that is also easy to customize to advance the democratization of biofabrication in TE. Full article

In recent years, natural polymers have gained significant attention due to their abundance, biodegradability and versatility, offering a promising alternative to conventional synthetic polymers. Among natural polymers, cellulose and hemicellulose hold a special place, being the most abundant plant polysaccharides in nature, which serve as key structural materials in the synthesis of hydrogels. Cellulose has attracted significant attention in the development of hydrogels due to the fact that it confers desirable mechanical properties, high water absorption and biocompatibility. Hemicellulose, although with a more amorphous structure than cellulose, contains various functional groups that facilitate its chemical modification. With an environmentally friendly nature and low cost, these polysaccharides have gained major interest and are highly appreciated by both the academic and industrial communities. This review comprehensively presents recent advances in the design and development of hydrogels made from renewable biopolymers—cellulose and hemicellulose—providing an in-depth exploration of the information recorded over the past five years. The latest strategies for the synthesis of hydrogels, their formation mechanisms and their most important properties are analyzed and summarized in detail from the perspective of physical and chemical crosslinking. A comparative analysis is performed between these hydrogels, highlighting not only the advantages and disadvantages of each type of hydrogel but also the main challenges associated with the balance between mechanical strength, swelling capacity, biodegradability and cost-effectiveness. Finally, the advanced biomedical applications of these hydrogels in areas such as drug delivery, wound dressings and tissue engineering are presented in detail. Full article

Ethnographic collections often incorporate composite objects consisting of various materials, including wood, textiles and metals. These objects are vulnerable to deterioration when iron fastenings corrode under humid environments, and their removal is therefore essential for the long-term preservation of artifacts. This study investigates the efficacy of the chelating agents Desferrioxamine B (DFO-B) and ethylenediaminetetraacetic acid (EDTA), applied in different gel formulations, in cleaning wooden and textile mock-ups stained with iron corrosion products. Three gel types were explored: xanthan gum, agarose and Nanorestore extra-dry gel with medium water retention (nano-MWR). The results indicated that xanthan gum exhibited the highest cleaning effectiveness but posed risks of residue deposition and surface damage due to the required clearance process. Agarose and nano-MWR gels proved to be less effective but showed potential for achieving high chelator efficacy with repeated applications. Agarose enhanced the chelators’ efficacy on textiles, while nano-MWR gel performed better on even wooden surfaces. No chemical damage was detected for either substrate across gel applications. The study concludes that a single gel formulation does not achieve equivalent cleaning efficacy on the two substrates of composite objects with a defined number of applications. Agarose in a semi-rigid state enhances the efficacy of textile treatment and may achieve comparable results on wood after repeated applications. Alternatively, a combined approach using agarose for textiles and nano-MWR gel for wood may optimize chelator performance on composite artifacts. Full article

Curcumin (Cur), a natural polyphenolic compound with potent antioxidant and anti-inflammatory properties, faces significant challenges in cosmeceutical applications due to its poor aqueous solubility and low bioavailability. Nanotechnology offers a promising approach to overcome these limitations and enhance the functionality of cosmetic formulations. In this work, Cur-loaded nanoemulsions (NEs) were developed using a droplet microfluidics technique to enhance Cur’s stability, bioavailability, and permeability for advanced cosmeceuticals. Various oils were screened for Cur solubility, with coconut oil demonstrating the highest capacity. Optimal oil-to-water flow ratios were determined to produce monodisperse NEs with controlled droplet sizes. Characterization via dynamic light scattering (DLS) revealed stable NEs with Z-potential values exceeding −30 mV at both room temperature and +4 °C for up to 21 days, indicating strong colloidal stability. Antioxidant activity was evaluated through DPPH assays, while in vitro permeability studies of the drug-loaded NEs after incorporation into suitable hydrogels, using Strat-M^® membranes mimicking human skin, demonstrated significantly enhanced penetration of the encapsulated Cur. In sum, this work highlights the potential of droplet microfluidics as a scalable and precise method for producing high-performance Cur NEs tailored for cosmeceutical applications. Full article