Search Results (1,005)

Titanium and its alloys are the most widely used metallic materials for bone contact implants. However, despite advances in implant technology, these alloys are still susceptible to post-operative clinical complications such as inflammation, which is often joined by infections and biofilm formation. A number of coatings were studied to overcome the drawbacks of these complications, but the controlled release of bioactive molecules over the first few days and the adhesion of the coating to the substrate remain recognized challenges. Carbon dots and the antibacterial potential of chiral carbon dots (CCDs) were recently reported, and their chirality was identified as a major contribution to the bactericidal effect. This study aimed to achieve a stimuli-responsive medium-term controlled release for up to one month. Two types of chiral carbon dots (CCDs) with distinct functional groups were incorporated into a stable and adherent biodegradable polymer coating, i.e., poly(lactic-co-glycolic acid) (PLGA). To enhance the coating adhesion, the titanium alloy surfaces were pre-treated and activated. The wettability, morphology, and surface composition of the coatings were characterized by contact angle, profilometry, SEM, and XPS, respectively. Coating degradation, adhesion, and CCDs release were studied at physiological pH (7.4) and at an acidic pH characteristic of an inflammatory site (pH 3.0) for up to one month. Their biological performances and blood compatibility were assessed as well. Degradation studies conducted over 28 days revealed a slow mass loss of approximately 10%, with maximum release rates for CCDs-OH and CCDs-NH₂ of 67% and 45% at pH 7.4, respectively. At pH 3.0 an inverse trend was observed with 49% and 59% maximum release after 28 days. Furthermore, the coatings did not exhibit any cytotoxic and hemolytic effects. These findings demonstrate the potential of this approach to providing titanium implants with pH-sensitive controlled release of bioactive CCDs lasting up to one month, which could address key challenges in implant-associated complications. Full article

In recent years, apatite-based materials have garnered significant interest, particularly for applications in tissue engineering. Apatite is most commonly employed as a coating for metallic implants, as a component in composite materials, and as scaffolds for bone and dental tissue regeneration. Among its various forms, hydroxyapatite (HAP) is the most widely used, owing to its natural occurrence in human and animal hard tissues. An emerging area of research involves the use of fluoride-substituted apatite, particularly fluorapatite (FAP), which can serve as a direct fluoride source at the implant site, potentially offering several biological and therapeutic advantages. However, substituting HAP with FAP may lead to unforeseen changes in material behavior due to the differing physicochemical properties of these two calcium phosphate phases. This study investigates the effects of replacing hydroxyapatite with fluorapatite in ceramic–polymer composite materials incorporating β-1,3-glucan as a bioactive polymeric binder. The β-1,3-glucan polysaccharide was selected for its proven biocompatibility, biodegradability, and ability to form stable hydrogels that promote cellular interactions. Nitrogen adsorption analysis revealed that FAP/glucan composites had a significantly lower specific surface area (0.5 m²/g) and total pore volume (0.002 cm³/g) compared to HAP/glucan composites (14.15 m²/g and 0.03 cm³/g, respectively), indicating enhanced ceramic–polymer interactions in fluoride-containing systems. Optical profilometry measurements showed statistically significant differences in profile parameters (e.g., Rp: 134 μm for HAP/glucan vs. 352 μm for FAP/glucan), although average roughness (Ra) remained similar (34.1 vs. 27.6 μm, respectively). Microscopic evaluation showed that FAP/glucan composites had smaller particle sizes (1 μm) than their HAP counterparts (2 μm), despite larger primary crystal sizes in FAP, as confirmed by TEM. XRD analysis indicated structural differences between the apatites, with FAP exhibiting a reduced unit cell volume (524.6 ų) compared to HAP (528.2 ų), due to substitution of hydroxyl groups with fluoride ions. Spectroscopic analyses (FTIR, Raman, ³¹P NMR) confirmed chemical shifts associated with fluorine incorporation and revealed distinct ceramic–polymer interfacial behaviors, including an upfield shift of PO₄³⁻ bands (964 cm⁻¹ in FAP vs. 961 cm⁻¹ in HAP) and OH vibration shifts (3537 cm⁻¹ in FAP vs. 3573 cm⁻¹ in HAP). The glucan polymer showed different hydrogen bonding patterns when combined with FAP versus HAP, as evidenced by shifts in polymer-specific bands at 888 cm⁻¹ and 1157 cm⁻¹, demonstrating that fluoride substitution significantly influences ceramic–polymer interactions in these bioactive composite systems. Full article

Poly(carboxybetaine methacrylate)s (PCBMA) belongs to a class of zwitterionic polymers that offer promising alternatives to polyethylene glycol (PEG) in biomedical applications. This review highlights how the unique zwitterionic structure of PCBMA dictates its strong antifouling behavior, low immunogenicity, and sensitivity to environmental stimuli such as pH and ionic strength. These features make PCBMA promising for designing advanced systems suited for complex biological environments. This review describes PCBMA-based materials—ranging from hydrogels, nanogels, and surface coatings to drug carriers and protein conjugates—and critically evaluates their performance in drug delivery, tissue engineering, diagnostics, and implantable devices. Comparative studies demonstrated that PCBMA consistently outperformed other zwitterionic polymers and PEG in resisting protein adsorption, maintaining bioactivity of conjugated molecules, and ensuring long circulation times in vivo. Molecular dynamics simulations provide additional information into the hydration shells and conformational behaviors of PCBMA in aqueous dispersions. These insights underscore PCBMA’s broad potential as a promising high-performance material for next generation healthcare technologies. Full article

Hydrogels are hydrophilic biocompatible polymers that can be used as a drug delivery material in different medical branches, including vital pulp therapy. The aim of this study is to characterize the physical and biological properties of the newly developed formula as a candidate direct pulp-capping material. The hydrogel composite was prepared from natural and synthetic origins (polyvinyl alcohol (PVA), hyaluronic acid (HA), and sodium alginate (SA)) with the incorporation of bioactive Moringa. Different formulas of hydrogel containing different concentrations were evaluated for physicochemical (FTIR, XRD, SEM, degradation, and swelling), mechanical (viscosity, folding endurance, film thickness), and biological (antioxidant, antibacterial, and cytotoxicity) properties. FTIR and XRD confirmed successful incorporation and partial cross-linking between moringa and hydrogel compounds. At low concentrations of moringa, the hydrogel formula showed integrity, scavenging activity, and homogeneity. The moringa-loaded films showed concentration-dependent antioxidant and antibacterial properties, especially at higher concentrations, with acceptable cytocompatibility. The low concentration of moringa (0.5%) may be considered a promising candidate as a novel pulp-capping agent supporting tissue healing and regeneration. Full article

Background/Objectives: Polymeric barrier membranes (BMs) are usually used in guided bone regeneration to isolate the bone defect from the surrounding tissue, favoring bone apposition. This study proposes a third-generation BM made of polycaprolactone (PCL), loaded with different concentrations of nano-hidroxyapatite (nHAP) and gentamicin (GEN), and fabricated by electrospinning. Methods: The mechanical properties of the polymer, together with the fabrication procedure, offer porosity with interconnectivity to permit cell adhesion and proliferation. Bacterial contamination of the BM can induce infection at the bone level, leading to unfavorable clinical outcomes of the regeneration procedure. Results: Therefore, BMs have been proposed as carriers for local GEN antibiotic therapy, demonstrating antibacterial properties against S. aureus, S. mutans, and P. aeruginosa, depending on the drug concentration, while being negligibly affected by the nHAP content. X-ray diffraction, FTIR-ATR, and SEM allowed for BM structural characterization, demonstrating the presence of GEN/nHAP and establishing the fiber diameter, which influences the mechanical properties in dry and wet conditions and the drug release behaviorA BM cytotoxicity assessment, performed over 1 and 5 days, revealed that a high nHAP concentration provided protection against cytotoxicity, in contrast to GEN, and that cell proliferation and cell adhesion increased in the presence of nHAP. The BM’s bioactivity was demonstrated by mineralization after 21 days in simulated body fluid in an SEM/EDX analysis. Conclusions: The electrospun 15 wt.% nHAP and 2 wt.% GEN-loaded third-generation BM could be a promising alternative for guided bone regeneration. Full article

Hydrogels have emerged as promising biomaterials for oral tissue regeneration thanks to their high-water content, excellent biocompatibility, and ability to mimic native tissue environments. These versatile materials can be tailored to support cell adhesion, proliferation, and differentiation, making them suitable for repairing both soft and hard oral tissues. When engineered from natural polymers and enriched with bioactive agents, hydrogels offer enhanced regenerative potential. Biopolymer-based hydrogels, derived from materials such as chitosan, alginate, collagen, hyaluronic acid, and gelatin, are particularly attractive due to their biodegradability, bioactivity, and structural similarity to the extracellular matrix, creating an optimal microenvironment for cell growth and tissue remodeling. Recent innovations have transformed these systems into multifunctional platforms capable of supporting targeted regeneration of periodontal tissues, alveolar bone, oral mucosa, dental pulp, and dentin. Integration of bioactive molecules, particularly essential oils, bio-derived constituents, cells, or growth factors, has introduced intrinsic antimicrobial, anti-inflammatory, and antioxidant functionalities, addressing the dual challenge of promoting tissue regeneration while at the same time attenuating microbial contamination in the oral environment. This review explores the design strategies, material selection, functional properties, and biomedical applications in periodontal therapy, guided tissue regeneration, and implant integration of natural polymer-based hydrogels enriched with bioactive factors, highlighting their role in promoting oral tissue regeneration. In addition, we discuss current challenges related to mechanical stability, degradation rates, and clinical translation, while highlighting future directions for optimizing these next-generation bioactive hydrogel systems in regenerative dentistry. Full article

Objective: This study aimed to evaluate the effect of incorporating bioactive particles (montmorillonite loaded with chlorhexidine, MMT/CHX) and different concentrations of silica nanoparticles (0%, 3%, 5%, 7%, 10%, and 15 wt%) into a universal dental adhesive on its degree of conversion, bond strength, water sorption, solubility, and antimicrobial activity. Materials and Methods: A universal adhesive was modified with 1 wt% MMT/CHX and varying amounts of silica nanoparticles. Degree of conversion was analyzed by Fourier transform infrared spectroscopy (FTIR), and microtensile bond strength was evaluated at 24 h, 6 months, and 12 months after water storage. Water sorption and solubility were measured according to ISO 4049, and antibacterial activity was tested against Streptococcus mutans using the agar diffusion method. Results: All experimental adhesives containing ≥7% silica showed significantly reduced water sorption and solubility. The presence of MMT/CHX imparted consistent antimicrobial activity across all experimental groups. Degree of conversion remained stable across all groups and storage periods. Notably, after 12 months, only the experimental groups maintained or improved bond strength, while the control group showed a significant reduction. Failure mode analysis indicated increased mechanical integrity with higher filler content. Conclusions: Incorporating 1 wt% MMT/CHX and ≥7 wt% silica into a universal adhesive improved long-term bond strength, reduced degradation, and introduced antibacterial properties without compromising polymer conversion. These findings support the potential of developing durable, bioactive adhesive systems for restorative dentistry. Clinical Significance: The incorporation of bioactive and reinforcing nanoparticles into universal adhesives enhances bond durability and introduces antibacterial properties without compromising polymerization. This innovation may lead to longer-lasting restorations and reduced risk of secondary caries in clinical practice. Full article

Bio-based nanofibers are gaining increasing attention in nanotechnology owing to their high surface area, interconnected porosity, and capacity to incorporate bioactive compounds. Among natural polymers, gelatin is particularly attractive because of its abundance, low cost, biodegradability, and versatile physicochemical properties. When processed by electrospinning, gelatin combines its amphiphilic nature with the structural advantages of nanofibers, enabling efficient interactions with a wide range of molecules. Nevertheless, pure gelatin nanofibers have drawbacks, such as poor mechanical strength and high-water solubility. To address these limitations, strategies including polymer blending, chemical and physical crosslinking, and multilayer biomaterials have been developed, resulting in improved stability, functionality, and application-specific performance. Therefore, this review summarizes recent advances in the fabrication and functionalization of gelatin nanofibers, highlighting how processing parameters and gelatin source influence electrospinning outcomes and fiber properties. Key applications are also discussed, with emphasis on biomedical, food, environmental, and biosensing. Therefore, gelatin nanofibers represent a sustainable and versatile biomaterial with high potential for advanced technological applications. Full article

Alginate hydrogels are promising tissue engineering biomaterials due to their biocompatibility and structural similarity to the extracellular matrix, but their poor mechanical strength, rapid degradation, and lack of bioactivity limit applications. To address this, a novel oxidized alginate/polyacrylamide/silica nanoparticle–gelatin (OA/PAAm/SiO₂-GT) composite hydrogel was developed using an interpenetrating polymer network (IPN) strategy, reinforced with silica nanoparticles and coated with gelatin. The influence of SiO₂ content on the microstructure, mechanical properties, swelling behavior, biodegradability, biomineralization, and cytocompatibility of the composite hydrogel was systematically investigated. Experimental results revealed that SiO₂ nanoparticles interacted with the polymer matrix within the composite hydrogel. With increasing content of SiO₂, the porosity of the OA/PAAm/SiO₂-GT composite hydrogel gradually decreased, while the mechanical properties exhibited a trend of initial enhancement followed by reduction, with maximum compressive strength at a SiO₂ content of 1.0% (w/v). Moreover, the incorporation of SiO₂ nanoparticles effectively modulated the swelling behavior, biodegradability, and biomineralization capacity of the composite hydrogel under in vitro conditions. Meanwhile, the OA/PAAm/SiO₂-GT composite hydrogel supported favorable cell adhesion and proliferation, optimal at a SiO₂ content of 0.5% (w/v). Furthermore, with increasing concentration of SiO₂ nanoparticles, the intracellular alkaline phosphatase (ALP) activity progressively increased, suggesting a promotive effect of SiO₂ nanoparticles on the osteogenic differentiation of MG63 cells. Therefore, the incorporation of SiO₂ nanoparticles into the OA/PAAm IPN matrices provides an effective means to tailor its biological properties, rendering it great potential for biomedical applications such as tissue engineering. Full article

Condensed tannins from grape seed residues show high antioxidant activity but low oral bioavailability because of their high degree of polymerization and covalent interactions with proteins. This study aimed to improve their bioaccessibility through depolymerization and encapsulation. Depolymerization was carried out using microwave-assisted SN1 reactions with gallic acid as a nucleophile under food-grade conditions, mainly producing epicatechin monomers with 99.8% polymer degradation efficiency. Importantly, the inhibition of ABTS●+ and DPPH● radicals remained unaffected (p > 0.05), indicating that depolymerization preserved the antioxidants’ redox function, maintaining about 90% of their inhibition activity. The products were encapsulated in phosphatidylcholine liposomes, which had nanometric sizes and high encapsulation efficiency (83.11%), and remained stable for up to 60 days. In vitro release of nanoliposomal epicatechin in a D1 simulant was less than 10% after 48 h, fitting a Weibull model (β = 0.07), suggesting sub-diffusive transport and demonstrating high bioactive retention capacity in aqueous systems. During in vitro digestion, bioaccessibility of gallic acid and epicatechin reached 95.61 ± 0.58% and 98.56 ± 0.81%, respectively, with a 2333% increase in the bioaccessible mass of flavan-3-ols in native liposomal condensed tannins, which otherwise showed no detectable bioaccessibility. These findings highlight the potential of polyphenols from agro-industrial waste with enhanced bioaccessibility for applications in nutraceuticals and functional foods. Full article

Nanobiocomposites are a class of biomaterials that include at least one phase with constituents in the nanometer range. Nanobiocomposites, a new class of materials formed by combining natural and inorganic materials (metals, ceramics, polymers, and graphene) at the nanoscale dimension, are expected to revolutionize tissue engineering and bone implant applications because of their enhanced corrosion resistance, mechanical properties, biocompatibility, and antimicrobial activity. Titanium-based nanocomposites are gaining attention in biomedical applications due to their exceptional biocompatibility, corrosion resistance, and mechanical properties. These composites typically consist of a titanium or titanium alloy matrix that is embedded with nanoscale bioactive phases, such as hydroxyapatite, bioactive glass, polymers, or carbon-based nanomaterials. Common methods for synthesizing Ti-based nanobiocomposites and their parts, including bottom-up and top-down approaches, are presented and discussed. The synthesis conditions and appropriate functionalization influence the final properties of nanobiomaterials. By modifying the surface roughness at the nanoscale level, composite implants can be enhanced to improve tissue integration, leading to increased cell adhesion and protein adsorption. The objective of this review is to illustrate the most recent research on the synthesis and properties of Ti-based biocomposites and their scaffolds. Full article

Cellulose and chitin are the most abundant natural polymers, and their exploitation paves the way for sustainable materials and products. This work investigates the preparation of composites based on acetylated cellulose and partially deacetylated chitin, i.e., chitosan, using versatile and robust air-assisted solution spraying (AASS), a potential method for preparing materials both in situ and ex situ. These materials, in the form of films, despite being prepared from high-molecular-weight and rigid biopolymers, show high flexibility (Young’s moduli below 1 GPa), outstanding mechanical properties (tensile strengths above 19 MPa and strain at failure higher than 2%), and bioactivity towards E. coli. The unprecedented flexibility, obtained without the use of any plasticizer or by casting with humidity control, is a direct consequence of the specific film morphology, whereby films are constituted from merging droplets. Depending on the solution properties (viscosity, surface tension), various droplet sizes are obtained, thus influencing the roughness and indirectly the wettability. Wettability analysis towards water and oil revealed higher contact angles towards both fluids as the content of chitosan increases in the composite what directly impacts packaging applications by better protecting the food. Besides this, higher chitosan content in the composite (7.5% w/w) enabled bioactivity against E. coli, where colony development was inhibited on the film surface compared with the neat cellulose acetate. This study shows a very high potential for AASS for obtaining uniform thin flexible films for food packaging applications, allowing faster drying and lower energy consumption than other film-forming techniques. Full article

Nisin, a food preservative lantibiotic produced by Lactococcus lactis, exhibits potent antimicrobial activity against a wide range of Gram-positive pathogens, including antibiotic-resistant strains such as methicillin-resistant Staphylococcus aureus (MRSA). This study explores the development of a novel nano drug delivery platform comprising nisin-loaded niosomes, formulated via microfluidic mixing, and integrated into fast-dissolving oral films for targeted buccal administration. Microfluidic synthesis enabled the precise control of critical parameters including the flow rate ratio, surfactant composition, and lipid concentration, resulting in uniform niosomal vesicles with optimal size distribution (100–200 nm), low polydispersity index, and high encapsulation efficiency. Span 40 and Span 60 were employed as non-ionic surfactants, stabilized with cholesterol to improve bilayer rigidity and drug retention. The encapsulated nisin demonstrated improved physicochemical stability over time and protection against proteolytic degradation, thus preserving its antimicrobial potency. The niosomal suspensions were subsequently incorporated into polymer-based oral films as a final dosage form composed of polyvinyl alcohol (PVA) as the primary film-forming polymer, polyethylene glycol 400 (PEG400) as a plasticizer, and sucralose and mint as a sweetener and flavoring agent, respectively. A disintegrant was added to accelerate film dissolution in the oral cavity, facilitating the rapid release of niosomal nisin. The films were cast and evaluated for thickness uniformity, mechanical properties, disintegration time, surface morphology, and drug content uniformity. The dried films exhibited desirable flexibility, rapid disintegration (<30 s), and consistent distribution of nisin-loaded vesicles. In vitro antimicrobial assays confirmed that the bioactivity of nisin was retained post-formulation, showing effective inhibition zones (16 mm) against Bacillus subtilis. This delivery system offers a promising platform for localized antimicrobial therapy in the oral cavity, potentially aiding in the treatment of dental plaque, oral infections, and periodontal diseases. Overall, the integration of microfluidic-synthesized nisin niosomes into oral films presents a novel, non-invasive strategy for enhancing the stability and therapeutic efficacy of peptide-based drugs in mucosal environments. Physicochemical characterization of the niosomes and niosome films was performed using Fourier-transform infrared spectroscopy (FTIR), differential scanning calorimetry (DSC) and thermogravimetric analysis (TGA) to evaluate thermal stability and scanning electron microscopy (SEM) to assess surface morphology. In vitro peptide release studies demonstrated sustained release from both niosomal suspensions and film matrices, and the resulting data were further fitted to established kinetic models to elucidate the underlying drug release mechanisms. This delivery system offers a promising platform for localized antimicrobial therapy in the oral cavity, potentially aiding in the treatment of dental plaque, oral infections, and periodontal diseases. Overall, the integration of microfluidic-synthesized nisin niosomes into oral films presents a novel, non-invasive strategy for enhancing the stability and therapeutic efficacy of peptide-based drugs in mucosal environments. Full article

Curcumin, a bioactive polyphenol from turmeric, faces significant challenges in food and pharmaceutical applications due to its poor water solubility, low stability, and limited bioavailability. In this study, curcumin–lecithin complexes (phytosomes) were spray-dried using maltodextrin as the carrier polymer to produce free-flowing powders with improved physicochemical properties. The powders were characterized based on moisture content, particle size, morphology, curcumin loading, thermal behavior, and stability under simulated gastrointestinal and thermal conditions. The lecithin–curcumin complexes exhibited high entrapment efficiency (up to 94%), a predominantly amorphous structure, and improved thermal and digestive stability compared to free curcumin. Particle size and wettability were influenced by carrier and curcumin ratios, with maltodextrin enhancing powder flowability and apparent solubility. Morphological analyses revealed spherical particles with core–shell structures, confirming successful complexation. The complexes protected curcumin from degradation at intestinal pH and elevated temperatures, highlighting their potential for enhanced bioavailability. These findings demonstrate that spray-dried curcumin–lecithin complexes with maltodextrin carriers offer a promising strategy to overcome curcumin’s solubility and stability limitations, supporting their application in functional foods and pharmaceuticals. Full article

Deep eutectic solvents (DESs) have emerged as sustainable and tunable alternatives to conventional solvents for the extraction of polysaccharides. This review presents a structure-informed framework linking DES composition to polysaccharide solubility, emphasizing the differential responsiveness of amorphous, interfacial, and crystalline domains. Amorphous polysaccharides are efficiently extracted under mild DES conditions, while crystalline polymers often require stronger hydrogen bond acceptors or thermal/mechanical activation. Beyond dissolution, DESs modulate key properties of the extracted polysaccharides, including molecular weight, monomer composition, and bioactivity. Comparative analysis highlights how acidic, basic, or metal-coordinating DESs selectively target distinct polymer classes. Emerging innovations, such as in situ DES formation, mechanochemical systems, and switchable solvents, enhance efficiency and reduce downstream processing demands. Furthermore, the integration of machine learning and COSMO-RS modeling enables predictive solvent design, reducing reliance on empirical screening. By combining mechanistic insight, compositional tailoring, and computational tools, this review provides a scientifically grounded perspective for advancing DES-mediated extraction processes and enabling structure-preserving, application-oriented recovery of polysaccharides in food, pharmaceutical, and biorefinery domains. Full article