Search Results (14,877)

Biopolymers such as chitosan are considered important candidates for water purification due to their non-toxicity, biodegradability, natural origin, biocompatibility, and potential for modification to provide additional capabilities, such as incorporating nanomaterials for magnetism to enable rapid separation or adding functional groups to enhance selectivity towards target adsorbates. This study investigated adsorption of Co (II), traced by Co-60 radionuclide, systematically evaluated in natural aquatic matrices selected according to water body type: seawater (Baltic Sea) and freshwater systems further distinguished as lentic (Lake Balsys) and lotic (Neris River) environments, using synthesized magnetite–chitosan nanocomposites (MCNs) with varying loadings of Fe₃O₄ (10–30 wt. %) nanoparticles providing different levels of magnetization. Comprehensive characterization (TEM, FTIR, AFM, XRD, and Mössbauer spectroscopy) confirmed successful integration of magnetite nanoparticles within the chitosan matrix and reproducible structural properties. An optimal magnetization of 11 emu/g was achieved at 20 wt. % Fe₃O₄, enabling rapid magnetic separation within <1 min without compromising sorption capacity. Adsorption isotherm models were applied to investigate the adsorption parameters, and sorption kinetics were studied, yielding a maximum adsorption capacity of 14.93 mg/g for MCN-10 in seawater and 11.95 mg/g for MCN-20 in freshwater with observed equilibrium within 120 min. These promising results indicate that the MCN is a suitable nanocomposite for the removal of Co (II) ions and the Co-60 radionuclide from aquatic media. Full article

Oxidative stress induced by excessive hydrogen peroxide (H₂O₂) is a critical pathological factor in skin aging, inflammatory disorders, and photodamage. While tocopherol (TCP) is a gold-standard antioxidant in cosmetics, its potential in H₂O₂-responsive systems remains underexplored. In this study, we report the design and characterization of ditocopheryl peroxalate (TOT), a novel tocopherol dimer linked via a H₂O₂-cleavable peroxalate linkage. TOT remains chemically stable under physiological conditions but undergoes selective chemiluminescence-like degradation upon exposure to H₂O₂, simultaneously scavenging H₂O₂ and liberating two TCP molecules. Notably, TOT demonstrated superior H₂O₂-scavenging efficiency and enhanced antioxidant and anti-inflammatory effects in H₂O₂-stimulated cells compared to monomeric TCP, while maintaining excellent biocompatibility. Structural analysis revealed that the rigid, linear configuration of TOT facilitates seamless integration into dipalmitoylphosphatidylcholine (DPPC) bilayers, yielding highly stable H₂O₂-responsive liposomes. These findings highlight TOT as a sophisticated multifunctional antioxidant platform for advanced cosmeceutical applications targeting photo-induced oxidative damage. Full article

The recent endeavor to establish a sustainable society, with respect to environmental protection and occupational health prevention, necessitates the development of environmentally friendly anodizing electrolytes. In addition, these electrolytes should be composed of biocompatible organic acids derived from renewable sources. In response to these challenges, there is a need to seek environmentally conscious alternatives to the widely used sulfuric acid anodization electrolyte. Accordingly, a comparative study was performed on the anodic polarization of AA2024-T3 aircraft alloy samples for 30 min at 0 or 20 °C. The respective electrolytes were composed of 0.5 M solutions of oxalic, citric, tartaric acids, or glycine. The comparative analysis included optical metallographic microscopy (OMM), scanning electron microscopy (SEM), color and wettability characterization, chemical composition analysis by X-ray photoelectron spectroscopy (XPS), and assessment of the corrosion-protective properties of the obtained layers. The latter were defined using electrochemical impedance spectroscopy (EIS) and potentiodynamic polarization scanning (PDS) after 24 h of exposure to a 0.5% NaCl solution. Among the most important conclusions is that the barrier properties of the layers obtained in citric and tartaric acid electrolytes remarkably exceed those of the film obtained in oxalic acid. The use of glycine does not result in film formation at all. The process temperature had a weaker effect than the electrolyte composition. The recent commitment to building a sustainable society, emphasizing environmental protection and occupational health, requires the development of eco-friendly anodization processes. These electrolytes should use biocompatible organic acids from renewable sources. Meeting these needs demands alternatives to the commonly used sulfuric acid anodization. Therefore, a comparative study was conducted on the anodic polarization of AA2024-T3 aircraft alloy samples for 30 min at 0 or 20 °C. The electrolytes consisted of 0.5 M solutions of oxalic, citric, tartaric acids, or glycine. Analytical methods included optical metallographic microscopy (OMM), scanning electron microscopy (SEM), color and wettability assessment, chemical composition analysis by X-ray photoelectron spectroscopy (XPS), and evaluation of corrosion resistance. The latter was measured using electrochemical impedance spectroscopy (EIS) and potentiodynamic polarization scanning (PDS) after 24 h in 0.5% NaCl solution. Key findings showed that barrier properties of the citric and tartaric acid layers substantially surpassed those of oxalic acid films. Glycine did not produce a film. The electrolyte composition had a greater impact than process temperature. Full article

Hyaluronic acid (HA)–based nanocapsules containing plant-derived bioactives are promising formulations for dermatological applications. In this study, nanocapsules containing extracts of Arnica montana, Calendula officinalis and Aesculus hippocastanum were synthesized and their structural and functional properties were characterized. Scanning electron microscopy confirmed the formation of spherical nanostructures with uniform morphology, while rheological analyses demonstrated stable viscoelastic behavior suitable for topical application. Their antimicrobial potential was assessed on microorganisms isolated from multiple regions of healthy human skin and opportunistic pathogens. A diverse panel of approx. 100 bacterial and fungal isolates was identified using MALDI-TOF MS. The antimicrobial activity of formulations was compared with commonly used disinfectants: H₂O₂, octenidine, isopropanol and topical ophthalmic antiseptic. Arnica-based formulations showed the strongest inhibitory effect against both Gram-positive and Gram-negative bacteria, whereas chestnut extract demonstrated selective activity against Candida spp. Calendula-based formulations exhibited limited antimicrobial activity. These findings demonstrate that plant-extract-loaded HA nanocapsules exhibit selective antimicrobial properties dependent on extract type and microbial group, supporting their potential as multifunctional components of future dermatological formulations. Full article

Children’s skin is uniquely vulnerable, requiring specialised design solutions that transcend traditional aesthetics. This exploratory study investigates the importance of paediatric dermatology in informing functional fashion design through expert medical perspectives. Using a qualitative approach, data were gathered from a purposive cohort of paediatric dermatologists and immunoallergologists and analysed through inductive thematic analysis. Findings identify four core themes: the physiological immaturity of children’s skin (notably the prevalence of atopic dermatitis), clothing’s role as a symptomatic aggravator rather than a primary aetiology, the clinical risks posed by chemical additives in synthetic textile processes, and the therapeutic potential of natural fibres and biofunctional agents. The data also highlights significant diagnostic constraints in paediatric patch testing, emphasising the necessity of proactive material safety. The findings suggest that integrating healthcare expertise into human-centred design may support the development of safer paediatric clothing solutions, ensuring that fashion industry innovation meets the physiological requirements of children. By transitioning from hazardous synthetic processes to biocompatible textiles, such as undyed natural fibres and medicinal plant-derived dyes, the industry can transform apparel from a potential irritant into a secondary protective barrier. This provides initial insights for developing clothing that safeguards the skin barrier and improves the overall wellbeing of vulnerable populations. Full article

Silica-based bioceramics are promising bone substitutes with tunable degradation and mechanical properties. We aimed to assess bone response in critical-size calvarial defects in rats, empty or filled with 3D-printed sphene ceramic (CaTiSiO₅) scaffolds produced using direct ink writing from preceramic polymers and reactive fillers. Scaffold characterization was performed using scanning electron microscopy, X-ray diffraction, porosity analysis, and compressive strength testing. Bilateral cylindrical 5 mm calvarial defects were created in 20 rats: one was randomly filled with sphene scaffold, while the contralateral remained empty. Ten animals were killed at 4 weeks, the rest at 8 weeks. Specimens were collected for micro-X-ray computed tomography (micro-CT) analysis, followed by undecalcified histology. The scaffolds exhibited porous structure with complete sphene phase purity and compressive strength of 17.91 MPa (SD 4.6). In vivo, no adverse event was noted during healing. Overall bone regeneration—as measured by BV/TV—was comparable between groups: Bone volume/total volume (BV/TV) increased over time in the empty and sphene groups, reaching ~40%, with no significant differences between groups or time points. BV/TV was significantly higher in the external regions of the defects compared to the internal areas in both groups at the two time points. The sphene group showed a significantly greater volume of new bone extending beyond the original cortical boundary at both 4 and 8 weeks (p = 0.013). In the sphene group histology revealed partial bone ingrowth within the scaffold, while bone in the control group was limited to defect edges. After 8 weeks, new bone adjacent to the cortical surface was thicker in the sphene group (p < 0.05). These initial findings are consistent with prior preclinical studies, supporting the biocompatibility and osteoconductive nature of sphene ceramic scaffolds. Full article

Flexible and biocompatible sensors are vital for a wide range of biomedical applications, including real-time health monitoring, intracranial pressure monitoring, knee replacement surgeries, wearables, and smart prosthetics. While various highly sensitive and stable pressure sensors have been demonstrated, they often lack the conformability and biocompatibility crucial for their wider application in various bio-integrated electronic systems. Herein, a piezoelectric pressure sensor is proposed using a hybrid polymer composite by leveraging the unique properties of Chitosan and Parylene C. Various material characterisations, such as XRD and FTIR, were performed to reveal structural and chemical characteristics of the novel composite material. Next, electromechanical characterisations of the pressure sensor were performed to reveal its dynamic sensing properties. The pressure sensor exhibits excellent sensitivity for both pressure and frequency, as well as cyclic stability (10³ cycles), wide pressure range (20–70 kPa), and biocompatibility. Full article

Novel, accurate molecular diagnostics are driving new advances across medicine, public health, and environmental monitoring. Surface-enhanced Raman spectroscopy (SERS) nanotags are powerful platforms for ultrasensitive, multiplexed, and quantitative detection of molecular targets. This review focuses on indirect sensing strategies, where SERS nanotags act as signal transducers, resulting in enhanced and unique Raman spectra upon binding of target analytes (high specificity) and allowing for ultralow limits of detection. These indirect SERS sensors typically consist of a plasmonic core, a Raman reporter molecule, and a ligand that targets the analyte of interest. Each of these components contributes to the sensitivity, stability, and selectivity of the system. Rational design of SERS nanotags requires balancing enhancement efficiency with reproducibility, biocompatibility, and assay integration. The choice of reporter molecules, for instance, governs spectral uniqueness and enables multiplexed detection of multiple analytes within a single sample. Recent advances in artificial intelligence and machine learning are accelerating nanotag development by enabling predictive control over nanostructure geometry, composition, and optical response. SERS nanotags are increasingly being integrated into diagnostic formats, such as lateral flow assays and microfluidic devices, offering both qualitative and quantitative analysis at the point of care. This review provides an overview of key design principles, common strategies for nanostructure functionalization and stabilization, and emerging biosensing applications, serving as a practical guide for researchers seeking to design and implement SERS nanotags. Full article

The excellent biocompatibility and favorable physicochemical properties of iron oxide nanoparticles have made them attractive candidates for magnetic resonance imaging. However, it remains challenging to synthesize high-performance T₁ contrast agents with controlled sizes and biocompatible coating materials. In this study, we demonstrate a simple and environmentally friendly approach for synthesizing ultra-small iron oxide nanoparticles using bovine serum albumin (BSA) as a template. Following synthesis, the iron oxide nanoparticles (Fe₃O₄) were oxidized to Fe₂O₃ via the addition of hydrogen peroxide, which resulted in enhanced T₁-weighted magnetic resonance contrast. The use of BSA not only stabilized the nanoparticles but also enabled precise control over nanoparticle size by adjusting the Fe-to-BSA molar ratio. This method yielded highly uniform and crystalline ultra-small nanoparticles ranging from approximately 3.7 to 7.9 nm in diameter. The T₁ contrast performance of the Fe₂O₃@BSA nanoparticles was evaluated at 3 T magnetic field. Among the synthesized samples, nanoparticles with sizes of 4.6 nm exhibited the strongest T₁ contrast enhancement along with low r₂/r₁ ratios. These features highlight their potential as promising alternatives to gadolinium-based contrast agents. In addition to their superior performance, this synthesis method is low-cost and non-toxic, making it suitable for scalable biomedical applications. Full article

As surgery is the first-line paradigm for many solid tumors, precision in preoperative diagnosis and intraoperative imaging is of significant importance. Dual MRI and NIR-II fluorescence imaging could fulfill precision imaging requirements in treating cancers, because of its deep penetration and real-time high spatiotemporal resolution. Thus, the design of dual MRI/NIR-II fluorescence contrast agents is crucial for the diagnosis and surgery of cancers. Herein, we developed optically transparent NaGdF4 matrix-based downshifting nanoparticles (DSNPs) co-doped with Nd³⁺, Yb³⁺, and Er³⁺ as a single nanoplatform for dual NIR-II fluorescence and T1-weighted MRI. Systematic dopant engineering reveals that optimal Nd³⁺ loading enhances cascade Nd → Yb → Er energy transfer and yields intense NIR-II emission at 1334 and 1521 nm upon 808 nm excitation with a relative quantum yield of 1.55, while the presence of Gd³⁺ in the optically transparent matrix imparts strong T1 contrast (4.98 s⁻¹ mM⁻¹). The Pluronic F-127 surface coating confers colloidal stability and biocompatibility. In vitro assays confirm negligible cytotoxicity and efficient cellular uptake. In vivo studies in subcutaneous 4T1 tumor-bearing mice demonstrate robust accumulation, high tumor-to-background contrast in both MRI/NIR-II fluorescence and enable precise NIR-II fluorescence imaging-guided surgery with real-time margin visualization. Therefore, dopant-engineered DSNPs represent a promising dual-modal imaging agent for deep-tissue diagnostic and real-time surgical guidance in precision oncology. Full article

Nanotechnology continues to advance rapidly, revealing previously unexplored directions in nanoscale communications. Biological and electromagnetic nanonetworks—established communication paradigms at the nanoscale—have shifted interest toward the middle and higher levels of the nanonetworking protocol stack. Motivated by the discovery of Cable Bacteria (CB) and their unique properties, we propose a theoretical model and framework for a new category of nanonetworks: bioelectrical nanonetworks (BioEN). This proposed framework combines the biocompatibility, sustainability and inherent nanodimensions of biological organisms with the networking performance of electromagnetic systems. Large-scale formations (e.g., 10,000 cells spanning nearly 2 cm), together with the electrical characteristics of CB, suggest the feasibility of guided electron-based transport that could complement diffusion-dominated nanonetworks, subject to resistive-capacitive (RC) constraints that remain to be quantified. Furthermore, we present a set of basic network architectures—such as star, ring, and tree—introducing a conceptual bio-multiplexer component, which utilizes CB to form a bioelectrical nanonetwork and illustrate core functionalities primarily at the network layer. Within this theoretical framework, BioEN is positioned as a potential enabler for diverse scientific, environmental, and technological applications, including health and ecosystem biosensing and bioremediation-oriented bioengineering. This work is conceptual and does not experimentally validate a deployed nanonetwork; instead, it establishes the design principles, abstractions, and architectural foundations intended to guide future implementation and experimental verification of bioelectrical nanonetworks. Full article

Laceration is one of the most common meniscus injuries, which can cause knee joint dysfunction. The treatment of meniscus injuries remains one of the greatest challenges in orthopedics. In this study, a three-dimensional sponge-like Poly(lactic acid)/Poly(3-hydroxybutyrate-co-4-hydroxybutyrate) (PLA/P(3HB-co-4HB)) scaffold with oriented microtubules was fabricated using an improved gradient thermal phase separation technique. The scaffold surface was modified by adsorbing gelatin. The surface-modified scaffolds and the unmodified scaffolds were divided into two groups. All preparation parameters were adjusted to meet tissue engineering requirements. The prepared scaffolds were tested for porosity, compression modulus, hydrophilicity, and degradability. Following scaffold preparation, induced differentiated rabbit bone marrow mesenchymal stem cells (BMSCs) were seeded to evaluate scaffold cytocompatibility. Cell proliferation was observed in the two scaffold groups, and cell viability was analyzed using CCK-8 assay, scanning electron microscopy (SEM), and confocal microscopy. Histological staining was performed to comparatively study cell synthetic function. Subsequently, tissue reconstruction and regeneration were evaluated following subcutaneous implantation of gelatin/PLA/P(3HB-co-4HB) scaffolds loaded with induced differentiated BMSCs in the dorsal regions of athymic nude mice. Results demonstrated that the gelatin/PLA/P(3HB-co-4HB) scaffold exhibited good cell compatibility, providing a suitable microenvironment for cell proliferation and differentiation. Furthermore, the scaffold supported the growth of seeded induced differentiated rabbit MSCs in vivo, maintaining meniscus cell phenotyping and function. The cell-laden scaffold has the potential to generate meniscus fibrocartilage. Full article

Feline immunodeficiency virus (FIV) is a lentivirus that exhibits significant structural and pathological similarities to human immunodeficiency virus (HIV), establishing it as a valuable model for HIV vaccine development. In this study, artificial intelligence (AI) and immunoinformatics were employed to design a novel multi-epitope DNA vaccine targeting conserved regions of the FIV gag, pol, and env genes. Predicted B-cell and T-cell epitopes were evaluated for their capacity to induce strong immune responses while minimizing allergenic or toxic effects and were linked to the immune adjuvant PADRE. Structural analysis indicated that the vaccine construct is stable, soluble, and biocompatible, with a well-folded tertiary structure that binds Toll-like receptor 9 (TLR9) and elicits robust humoral and cellular immune responses. These findings identify a promising FIV vaccine candidate and provide insights for the development of next-generation HIV vaccines. Full article

Myocardial infarction is a major cardiovascular event that leads to heart failure and death. Although current vascular regeneration and pharmacological therapies can salvage some myocardial tissue, they cannot effectively reverse established necrosis, fibrosis, or adverse ventricular remodeling, thus necessitating novel repair strategies. Silk fibroin (SF), a natural biomaterial, has emerged as an ideal substrate for cardiac tissue engineering owing to its excellent biocompatibility, tunable mechanical properties, and controllable biodegradability. This paper systematically reviews SF-based myocardial repair strategies: SF cardiac patches can be directly applied to infarct areas, providing mechanical support and delivering bioactive substances, while injectable SF hydrogels can be formed in situ via minimally invasive methods, serving as three-dimensional delivery vehicles for cells or drugs. These approaches synergistically promote cardiac repair through multiple mechanisms, including active regulation of inflammation, promotion of angiogenesis, and inhibition of fibrosis. Future development of SF-based therapies will focus on creating smart responsive materials, constructing biomimetic structures via advanced biomanufacturing techniques, and accelerating clinical translation, thereby providing comprehensive solutions for myocardial infarction repair. Full article

Hydrogels constructed from natural biomacromolecules with multifunctional properties, such as improved mechanical strength, ionic stability, biocompatibility, and ionic conductivity, are highly desirable for advanced food and biomedical applications, yet remain challenging to design. Although alginate is one of the most widely used hydrogel-forming polysaccharides due to its biocompatibility and gelation ability, its intrinsic limitations often hinder the development of hydrogels with fully optimized performance. This review provides a systematic comparison of alginate-based composite hydrogels formed with complementary biopolymers, including whey proteins, gelatin, pectin, starch, and chitosan, focusing on their synergistic effects on structural, mechanical, and functional properties. Recent studies are critically analyzed to elucidate how polymer–polymer interactions influence gel network formation, environmental ionic stability, and encapsulation performance. Particular attention is given to fabrication strategies and formulation parameters that enhance the immobilization and controlled release of probiotics, vitamins, polyphenols, and other bioactive compounds. By integrating current knowledge on structure–function relationships and processing approaches, this review offers practical design guidelines for the development of multifunctional alginate-based hydrogel systems for applications in functional foods and nutraceutical delivery. Full article