Search Results (306)

Background/Objectives: This study aimed to evaluate the safety and efficacy of chitosan-based bioadhesive films for facilitating the topical delivery of curcumin in skin cancer treatment, addressing the pharmacokinetic limitations associated with oral administration. Methods: The films, which incorporated curcumin, were formulated using varying proportions of chitosan, polyvinyl alcohol, Poloxamer^® 407, and propylene glycol. These films were assessed for stability, drug release, in vitro skin permeation, cell viability (with and without radiotherapy), and skin irritation. Results: The films demonstrated physical stability and preserved curcumin content at room temperature for 90 days. Drug release was effectively controlled during the first 8 h, with release rates ranging from 51.6 ± 4.8% to 65.6 ± 13.0%. The films also enhanced drug penetration into the skin compared to a curcumin solution used as a control (stratum corneum: 1.3 ± 0.1 to 1.9 ± 0.8 µg/cm²; deeper skin layers: 1.7 ± 0.1 to 2.7 ± 0.2 µg/cm²). A cytotoxicity test on metastatic melanoma cells showed that curcumin at topical doses exerted activity similar to that delivered via the skin. Furthermore, curcumin alone was more effective in inhibiting tumor cells than radiotherapy alone (p < 0.01), with no additional benefit observed when curcumin was combined with radiotherapy. Finally, irritation tests confirmed that the films were safe for topical application. Conclusion: The developed chitosan-based bioadhesive films represent a promising alternative for the topical treatment of skin tumors using curcumin. Full article

The development of skin-protective materials that prevent the adhesion of cnidarian nematocysts and enhance the mechanical strength of these materials is crucial for addressing the issue of jellyfish stings. This study aimed to construct superhydrophobic nanomaterials capable of creating a surface that inhibits nematocyst adhesion, therefore preventing jellyfish stings. We investigated wettability and nematocyst adhesion on four different surfaces: gelatin, polydimethylsiloxane (PDMS), dodecyl trichlorosilane (DTS)-modified SiO₂, and perfluorooctane triethoxysilane (PFOTS)-modified TiO₂. Our findings revealed that an increase in hydrophobicity significantly inhibited nematocyst adhesion. Furthermore, DTS-modified sprayed SiO₂ and PFOTS-modified sprated TiO₂ were further enhanced with low-surface-energy substances—cellulose nanofibers (CNF) and chitin nanocrystals (ChNCs)—to improve both hydrophobicity and mechanical strength. After incorporating CNF and ChNCs, the surface of s-TiO₂-ChNCs exhibited a contact angle of 153.49° even after undergoing abrasion and impact tests, and it maintained its hydrophobic properties with a contact angle of 115.21°. These results indicate that s-TiO₂-ChNCs can serve as an effective skin coating to resist tentacle friction. In conclusion, this study underscores the importance of utilizing hydrophobic skin materials to inhibit the adhesion of tentacle nematocysts, providing a novel perspective for protection against jellyfish stings. Full article

Background/Objectives: The demand for natural-based formulations in chronic wound care has increased, driven by the need for biocompatible, safe, and effective treatments. Natural polysaccharide-based emulsions enriched with vegetable oils present promising benefits for skin repair, offering structural support and protective barriers suitable for sensitive wound environments. This study aimed to develop and evaluate semisolid polysaccharide-based emulsions for wound healing, incorporating avocado (Persea gratissima) and blackcurrant (Ribes nigrum) oils (AO and BO, respectively). Both gellan gum (GG) and kappa-carrageenan (KC) were used as stabilizers due to their biocompatibility and gel-forming abilities. Methods: Four formulations were prepared (F1-GG-AO; F2-KC-AO; F3-GG-BO; F4-KC-BO) and evaluated for physicochemical properties, spreadability, rheology, antioxidant activity, occlusive and bioadhesion potential, biocompatibility, and wound healing efficacy using an in vitro scratch assay. Results: The pH values (4.74–5.06) were suitable for skin application, and FTIR confirmed excipient compatibility. The formulations showed reduced occlusive potential, pseudoplastic behavior with thixotropy, and adequate spreadability (7.13–8.47 mm²/g). Lower bioadhesion indicated ease of application and removal, enhancing user comfort. Formulations stabilized with KC exhibited superior antioxidant activity (DPPH scavenging) and fibroblast biocompatibility (CC_50% 390–589 µg/mL) and were non-hemolytic. Both F2-KC-AO and F4-KC-BO significantly improved in vitro wound healing by promoting cell migration compared to other formulations. Conclusions: These findings underscore the potential of these emulsions for effective wound treatment, providing a foundation for developing skin care products that harness the therapeutic properties of polysaccharides and plant oils in a natural approach to wound care. Full article

Due to their indisputable biocompatibility and abundant source, biopolymers are widely used to prepare hydrogels for skin tissue engineering. Among them, cellulose is a great option for this challenging application due to its increased water retention capacity, mechanical strength, versatility and unlimited availability. Since algae are an unexploited source of cellulose, the novelty of this study is the decellularization of two different species, freshly collected from the Black Sea coast, using two different chemical surfactants (sodium dodecyl sulphate and Triton X-100), and characterisation of the resulted complex biopolymeric 3D matrices. The algae nature and decellularization agent significantly influenced the matrices porosity, while the values obtained for the hydration degree included them in hydrogel class. Moreover, their capacity to retain and then controllably release an anti-inflammatory drug, ibuprofen, led us to recommend the obtained structures as drug delivery systems. The decellularized macroalgae hydrogels are bioadhesive and cytocompatible in direct contact with human keratinocytes and represent a great support for cells. Finally, it was noticed that human keratinocytes (HaCaT cell line) adhered and populated the structures during a monitoring period of 14 days. Full article

This study explores for the first time the impact of chitosan (CS) with varying molecular weights (MW), orange peel extract concentration, and hydroxypropyl methylcellulose (HPMC) content on the formulation of buccal tablets for treating oral infections. Utilizing a statistical design of experiments (DoE), nine different formulations were evaluated for mechanical properties, dissolution behavior, mucoadhesion, and biological activity. A formulation with high CS MW, 60% orange peel extract, and 8% HPMC, emerged as the optimal formulation, demonstrating superior tabletability, compressibility, and compactibility. Dissolution studies indicated that hesperidin release followed the Higuchi model, with higher extract content enhancing this phenomenon. Mucoadhesion improved with increased HPMC and CS concentrations, although higher extract content reduced bioadhesion. Biological assays showed that higher extract levels boosted antioxidant activity, while CS primarily contributed to anti-inflammatory effects. The optimized formulation exhibited broad antimicrobial activity against key oral pathogens, surpassing the effectiveness of the individual components. Principal component analysis (PCA) further confirmed the significant influence of extract content on tablet properties. These findings suggest that the optimized tablet formulation holds promise for effective buccal delivery in the treatment of oral infections, warranting further investigation in clinical settings. Full article

Wound healing is important for skin after deep injuries or burns, which can lead to hospitalization, long-term morbidity, and mortality. In this field, tissue-engineered skin substitutes have therapy potential to assist in the treatment of acute and chronic skin wounds, where many requirements are still unmet. Hence, in this study, a novel type of biocompatible ternary polymer hybrid hydrogel scaffold was designed and produced through an entirely eco-friendly aqueous process composed of carboxymethyl cellulose, chitosan, and polyvinyl alcohol and chemically cross-linked by citric acid, forming three-dimensional (3D) matrices, which were biofunctionalized with L-arginine (L-Arg) to enhance cellular adhesion. They were applied as bilayer skin biomimetic substitutes based on human-derived cell cultures of fibroblasts and keratinocytes were seeded and grown into their 3D porous structures, producing cell-based bio-responsive hybrid hydrogel scaffolds to assist the wound healing process. The results demonstrated that hydrophilic hybrid cross-linked networks were formed via esterification reactions with the 3D porous microarchitecture promoted by foam templating and freeze-drying. These hybrids presented chemical stability, physicochemical properties, high moisture adsorption capacity, surface properties, and a highly interconnected 3D porous structure well suited for use as a skin substitute in wound healing. Additionally, the surface biofunctionalization of these 3D hydrogel scaffolds with L-arginine through amide bonds had significantly enhanced cellular attachment and proliferation of fibroblast and keratinocyte cultures. Hence, the in vivo results using Hairless mouse models (an immunocompromised strain) confirmed that these responsive bio-hybrid hydrogel scaffolds possess hemocompatibility, bioadhesion, biocompatibility, adhesiveness, biodegradability, and non-inflammatory behavior and are capable of assisting the skin wound healing process. Full article

The bioadhesion of bacteria to the surface of samples with Ti–TiN, Zr–ZrN, Zr–(Zr, Nb)N, and Zr–(Zr, Hf)N coatings was studied via incubation with gram-positive strains of Staphylococcus aureus. The samples were kept at 25 °C for 30 days in a 3% NaCl solution. The deposition of coatings slows, whereas oxidation processes intensify. The oxygen content on the TiN and (Zr, Nb)N coating surfaces was higher than that of the Ti sample without a coating. Samples with ZrN and, especially, (Zr, Hf)N coatings resist oxidation better. Regarding bioactivity toward S. aureus, the highest density of biological forms was observed on the surfaces of TiN and (Zr, Hf)N coatings. The lowest density was on the surfaces of uncoated, ZrN-coated, and (Zr, Nb)N-coated samples. On Ti–TiN, Zr–ZrN, and Zr–(Zr, Nb)N coatings, the formation of surface biostructures of a filamentary type was observed. In the uncoated sample, the biostructures have an island character, and in the sample with a Zr–(Zr, Hf)N coating, the formation of extensive areas of biostructures was observed. Between the biostructures and coating, a layer 5 to 15 nm thick was observed, presumably associated with bacterial adhesion. The presence of biostructures on the coating surface can activate or slow oxidation processes. Full article

Background/Objectives: Paediatric eosinophilic oesophagitis (EoE) treatment is challenging due to the limited number of age-appropriate formulations. This study aims to develop and evaluate oral viscous suspensions and solid formulations of budesonide (BUD), focusing on their in vitro mucoadhesive properties, to enhance drug delivery and therapeutic outcomes in paediatric EoE. Methods: This study encompasses the development of oral viscous suspensions and orodispersible solid formulations (moulded tablets and 3D-printed dosage forms) containing BUD. The formulations underwent quality control tests as per the European Pharmacopoeia, chemical stability assessments, and an in vitro evaluation of their mucoadhesiveness properties. Results: A validated analytical method enabled accurate BUD quantification and efficient extraction, and all developed formulations demonstrated chemical stability for 30 days, meeting Ph. Eur. quality standards. Three-dimensional printing using SSE successfully produced 1 mg and 0.5 mg BUD printlets, complying with quality tests for conventional tablets. Formulations containing xanthan gum (L2-XG and P1-0.5-XG) exhibited superior mucoadhesive properties. L2-XG showed significantly higher mucoadhesion than L1-MC. Among the solid formulations, P1-0.5-XG demonstrated the highest mucoadhesive properties. Conclusions: This is the first study to develop solid oral dosage forms of BUD at a very low dose, specifically for paediatric use. The results highlight the potential of 3D printing for developing individualised orodispersible BUD formulations with improved bioadhesion for paediatric EoE treatment. The L2-XG formulation and the XG-containing printlets are the most promising formulations in terms of increasing contact time with the oesophageal mucosa, which could translate into improved therapeutic efficacy in this patient population. Full article

The Rhipicephalus microplus tick causes enormous economic losses in livestock farming around the world. Despite several promising studies carried out with plant extracts such as Achyrocline satureioides against this ectoparasite, a major obstacle is related to pharmaceutical presentation forms. There is no study showing xantan gum-based hydrogel and polycaprolactone nanoparticles containing A. satureioides extract against R. microplus larvae. The objective of this study was to incorporate A. satureioides extract to develop a nanoformulation (AScn) and a hydrogel (ASlh) and evaluate them against R. microplus larvae with the purpose of increasing the contact time of the extract with the larvae and improve the effectiveness. The ethanolic extracts were incorporated in polycaprolactone nanoparticles and characterized via analysis of the mean hydrodinamic diameter and polidispersity index. The xanthan gum-based hydrogel formulation was prepared with crude extract of A. satureioides 40 mg/mL, 0.25% xanthan gum, and 8% poloxamer, to determine the bioadhesiveness of the formulation in bovine leather and the flow rate of the formulation in the animal. The results in larvae demonstrated that when evaluated in the form of a hydrogel (ASlh), mortality was higher, with 91.48% mortality at a concentration of 20 mg/mL presenting itself as an interesting alternative for controlling this ectoparasite. Full article

Background: Gliadins have aroused significant interest in the last decade as suitable biomaterials for food and pharmaceutical applications. In particular, the oral route is the preferred method of administration for gliadin-based formulations, due to the affinity of this biomaterial for the gut mucosa. However, up to now, this has been demonstrated only by means of in vivo or ex vivo studies. Methods: This is why, in this study, various in vitro techniques were employed in order to evaluate the ability of polymeric nanoparticles, made up of a commercial grade of the protein and an etheric surfactant, to interact with porcine gastric mucin. The nanosystems were also used for the encapsulation of thiamine hydrochloride, used as a model of a micronutrient. Results: The resulting systems were characterized by a mean diameter of ~160–170 nm, a narrow size distribution when 0.2–0.6 mg/mL of thiamine was used, and an encapsulation efficiency between 30 and 45% of the drug initially employed. The incubation of the gliadin nanosystems with various concentrations of porcine gastric mucin evidenced the ability of the carriers to interact with the mucus glycoprotein, showing a decreased Zeta potential after a 4 h incubation (from ~−30 to −40 mV), while demonstrating that the encapsulation of the drug did not affect its bioadhesive features. Conclusions: Altogether, these data support the conceivable application of gliadin nanoparticles as formulations for the oral administration of bioactive compounds. Full article

Mitigating acid mine drainage (AMD) at its source, specifically within rocks containing pyrite in underwater environments, poses a significant environmental challenge worldwide. Existing passivation techniques are primarily designed for open-air conditions, involving direct contact with coating materials at a solid–liquid interface, making them ineffective beneath a water barrier. In this study, we introduce a novel passivation method inspired by the design of underwater bio-adhesives. Tannic acid (TA) combined with polyethylene glycol (PEG) was employed to form a hydrophobic film directly on the pyrite surface, overcoming water resistance and addressing the limitations of current techniques. Electrochemical experiments and chemical leaching experiments were conducted to evaluate the oxidation resistance of the passivating films. TA–PEG-coated pyrite exhibited a lower oxidation rate and a higher static contact angle of 126.2°, achieving suppression efficiencies of 71.6% for total Fe release and 68.1% for total S release. A comprehensive characterization approach, including scanning electron microscopy (SEM), Fourier transform infrared spectroscopy (FTIR), Raman spectroscopy, and X-ray photoelectron spectroscopy (XPS), was employed to investigate the passivation mechanism. The results of this study may provide new insights into the preparation of simpler and greener passivating agents to suppress pyrite oxidation at its source in underwater environments. Full article

Interfaces between implantable bioelectrodes and tissues provide critical insights into the biological and pathological conditions of targeted organs, aiding diagnosis and treatment. While conventional bioelectronics, made from rigid materials like metals and silicon, have been essential for recording signals and delivering electric stimulation, they face limitations due to the mechanical mismatch between rigid devices and soft tissues. Recently, focus has shifted toward soft conductive materials, such as conductive hydrogels and hydrogel nanocomposites, known for their tissue-like softness, biocompatibility, and potential for functionalization. This review introduces these materials and provides an overview of recent advances in soft hydrogel nanocomposites for implantable electronics. It covers material strategies for conductive hydrogels, including both intrinsically conductive hydrogels and hydrogel nanocomposites, and explores key functionalization techniques like biodegradation, bioadhesiveness, injectability, and self-healing. Practical applications of these materials in implantable electronics are also highlighted, showcasing their effectiveness in real-world scenarios. Finally, we discuss emerging technologies and future needs for chronically implantable bioelectronics, offering insights into the evolving landscape of this field. Full article

Amidoxime-functionalized hydrogels are one of most promising adsorbents for high-efficiency uranium (U) extraction from seawater, but bioadhesion on their surface seriously decreases their adsorption efficiency and largely shortens their service life. Herein, a semi-interpenetrating zwitterion–poly(amidoxime) (ZW-PAO) hydrogel was explored through introducing a PAO polymer into a poly [3-(dimethyl 4-vinylbenzyl amino) propyl sulfonate] (PDVBAP) polyzwitterionic (PZW) network via ultraviolet (UV) polymerization. Owing to the anti-polyelectrolyte effect of the PZW network, this ZW-PAO hydrogel can provide excellent super-hydrophilicity in seawater for high-efficiency U-adsorption from seawater. Furthermore, the ZW-PAO hydrogel had outstanding anti-biofouling performance for both highly enhanced U-adsorption and a relatively long working life in natural seawater. As a result, during only 25 days in seawater (without filtering bacteria), the U-uptake amount of this ZW-PAO hydrogel can reach 9.38 mg/g and its average rate can reach 0.375 mg/(g∙day), which is excellent among reported adsorbents. This work has explored a promising hydrogel for high-efficiency U-recovery from natural seawater and will inspire new strategy for U-adsorbing materials. Full article

Background/Objectives: This study developed and characterized hydrogels (HG-CGG) and films (F-CGG) based on cationic guar gum (CGG) for application in wound healing. Methods: HG-CGG (2% w/v) was prepared by gum thickening and evaluated for pH, stability, spreadability, and viscosity. F-CGG was obtained using an aqueous dispersion of CGG (6% w/v) and the solvent casting method. F-CGG was characterized for thickness, weight uniformity, morphology, mechanical properties, hydrophilicity, and swelling potential. Both formulations were evaluated for bioadhesive potential on intact and injured porcine skin, as well as antioxidant activity. F-CGG was further studied for biocompatibility using hemolysis and cell viability assays (L929 fibroblasts), and its wound-healing potential by the scratch assay. Results: HG-CGG showed adequate viscosity and spreadability profiles for wound coverage, but its bioadhesive strength was reduced on injured skin. In contrast, F-CGG maintained consistent bioadhesive strength regardless of skin condition (6554.14 ± 540.57 dyne/cm² on injured skin), presenting appropriate mechanical properties (flexible, transparent, thin, and resistant) and a high swelling capacity (2032 ± 211% after 6 h). F-CGG demonstrated superior antioxidant potential compared to HG-CGG (20.50 mg/mL ABTS+ radical scavenging activity), in addition to exhibiting low hemolytic potential and no cytotoxicity to fibroblasts. F-CGG promoted the proliferation of L929 cells in vitro, supporting wound healing. Conclusions: Therefore, CGG proved to be a promising material for developing formulations with properties suitable for cutaneous use. F-CGG combines bioadhesion, antioxidant activity, biocompatibility, cell proliferation, and potential wound healing, making it promising for advanced wound treatment. Full article

The possibility of producing and designing bio-epoxides based on the natural polyphenol lignin/epoxidized lignin and tannic acids for application as wood adhesives is presented in this work. Lignin and tannic acids contain numerous reactive hydroxyl phenolic moieties capable of being efficiently involved in the reaction with commercial epoxy resins as a substitute for commercial, non-environmentally friendly, toxic amine-based hardeners. Furthermore, lignin was epoxidized in order to obtain an epoxy lignin that can be a replacement for diglycidyl ether bisphenol A (DGEBA). Cross-linking of bio-epoxy epoxides was investigated via FTIR spectroscopy and their prospects for wood adhesive application were evaluated. This study determined that the curing reaction of epoxy resin can be conducted using lignin/epoxy lignin or tannic acid. Tensile shear strength testing results showed that lignin and tannic acid can effectively replace amine hardeners in epoxy resins. Examination of the failure of the samples showed that all samples had a 100% fracture through the wood. All samples of bio-epoxy adhesives displayed significant tensile shear strength in the range of 5.84–10.87 MPa. This study presents an innovative approach to creating novel cross-linked networks of eco-friendly and high-performance wood bio-adhesives. Full article