Search Results (4,766)

Diabetic foot ulcers (DFUs) are complex to heal and can lead to amputations and high healthcare costs. To address this, a promising alternative is the creation of electrospun fiber scaffolds for wound dressings. This study fabricated these scaffolds using a blend of natural polymers—chitosan (CTS), polyvinyl alcohol (PVA), and hyaluronic acid (HA)—along with antibacterial silver (Ag) and zinc oxide (ZnO) nanoparticles. The researchers conducted comprehensive analyses, including physicochemical, morphological, and biological assessments. The Ag structures showed potential as microbicidal agent, while the ZnO nanoparticles demonstrated photoactivity and the ability to generate reactive oxygen species (ROS) for antibacterial action. The resulting PVA-CTS-HA-Ag-ZnO scaffolds were found to be both hemocompatible and non-hemolytic, meaning they are safe for use with blood. The cytotoxicity evaluation using the ISO 10993-5 standard showed that the incorporation of CTS and HA decreased cytotoxicity of pure PVA, obtaining non-cytotoxic scaffolds (viability > 70%). Electrospun scaffolds composed with Ag-ZnO NPs in 50-50 and 70-30 ratios also maintained this biocompatibility, while the 30-70 ratio (Ag-ZnO) showed a cytotoxic effect, suggesting a ZnO concentration-dependent effect. These findings confirm that these materials are suitable for supporting skin cell regeneration, having a high potential for use as interactive dressings for treating chronic wounds. Full article

Nicotinamide adenine dinucleotide (NAD⁺) boosting can sustain energy metabolism and neurovascular stability in the retinal tissue. Depletion of NAD⁺ is linked to the development of pathological retinal conditions, such as age-related macular degeneration (AMD) and diabetic retinopathy (DR). Mitochondrial dysfunction, oxidative stress, and inflammation occur in these diseases. This review summarizes substantial evidence of therapeutic NAD⁺ boosters, including nicotinamide, nicotinamide mononucleotide, or nicotinamide riboside. They help improve mitochondrial function and lessen neurovascular injury. We also emphasize the importance of natural products and sirtuins in facilitating cytoprotective effects through the regulation of mitochondrial balance and inflammation. Developments in drug delivery methods, such as nanoparticle encapsulation and targeted eye treatments, are promising for enhancing the bioavailability and effectiveness of NAD⁺ boosters. The novelty of this work is its combination of mechanistic insights regarding NAD⁺ metabolism with efficacy data from preclinical studies. Furthermore, natural products may work together to boost their therapeutic effects against retinal damage. Together, our review article highlights NAD⁺ metabolism as a potential therapeutic target for addressing retinal degeneration and maintaining vision in aging, neurologic disorders, and various metabolic diseases, including diabetes. Full article

According to existing ecological problems, one of the promising developments is the creation of polyfunctional materials, which can be biodegradable, along with possessing antibacterial activity. The present research proposes biocomposites based on PLA with silver nanoparticles (AgNPs) and natural polysaccharides obtained in a twin-screw extruder. Introduction of polysaccharides to PLA-based biocomposites with/without AgNPs led to significant decrease in the elastic modulus and tensile strength, while the elongation at break remained almost unchanged. Thanks to the presence of natural polysaccharides, there was intensified biodegradation in soil despite the AgNP availability. The maximal mass loss was 29% for the PLA–PEG₁₀₀₀–starch + AgNPs (80:10:10 + 0.5 wt%) biocomposite. Analyses of the systems before and after soil exposure were carried out using DSC and FTIR spectroscopy methods. According to a thermal analysis, it was found that PLA crystalline regions degrade during exposure to soil. The same feature was detected during the spectral analysis. The intensity of the characteristic absorption bands of PLA decreased. Furthermore, it was found that the dark areas on the surface of the materials are of a polysaccharide nature and may be signs of biofouling of the materials by microbial flora. The tests on fungus resistance showed that biocidal additives such as AgNPs in PLA-based biocomposites with polysaccharides did not inhibit the development of mycelial fungi–biodestructors. And the increased amount of chitosan in the films contributed to their more active destruction by the end of the observation period. It was demonstrated that such biocomposites can inhibit bacterial growth. Full article

Background: Minimally invasive hyperthermia and regenerative therapies require materials that deliver precise, localized heat without compromising biocompatibility. Most conventional polymers are thermally insulating and challenging to control in vivo, motivating this review. Objectives: We aimed to (i) examine the use of thermally enhanced biopolymers in hyperthermia-based therapies, (ii) appraise evidence from clinical and preclinical studies, (iii) identify and classify principal applications in regenerative medicine. Methods: A PRISMA-guided systematic review (2020–2025) with predefined inclusion/exclusion criteria was conducted and complemented by a bibliometric analysis using VOSviewer for mapping and visualization. Results: Modifying biopolymers—via functionalization with photothermal or magnetic nanoagents (Au; Fe₂O₃/Fe₃O₄/CoFe₂O₄; CuS; Ag; MXenes, e.g., Nb₂C), crosslinking strategies, and hybrid formulations—significantly increased thermal conductivity, enabling localized hyperthermia and controlled drug release. In vitro and in vivo studies showed that europium-doped iron oxide nanoparticles embedded in chitosan generated heat efficiently while sparing healthy tissues, underscoring the need to balance biocompatibility and thermal performance. Hydrogel systems enriched with carbon nanomaterials (graphene, carbon nanotubes) and matrices such as GelMA, PNIPAM, hyaluronic acid, and PLA/PLGA demonstrated tissue compatibility and effective thermal behavior; graphene was compatible with neural tissue without inducing inflammation. Conclusions: Thermally conductive biopolymers show growing potential for oncology and regenerative medicine. The evidence supports further academic and interdisciplinary research to optimize safety, performance, and translational pathways. Full article

Small extracellular vesicles (small EVs) play pivotal roles in intercellular communication and pregnancy maintenance, but their clinical significance in preeclampsia (PE) remains unclear. We obtained plasma samples from non-pregnant women, healthy pregnant women, and patients with early-onset (EoPE) and late-onset PE (LoPE). Small EVs were isolated using ultracentrifugation and validated using transmission electron microscopy and nanoparticle tracking analysis; in addition, Western blotting was performed to identify suitable surface markers for plasma-derived small EVs. In our analysis, we consistently detected cluster of differentiation 9 (CD9), whereas classical markers such as cluster of differentiation 63 (CD63) and tumor susceptibility gene 101 (TSG101) were absent. In a prospective, nested case–control study, we analyzed first-trimester samples by using a CD9-based ELISA for small-EV quantification. The number of small EVs did not significantly differ between non-pregnant and healthy pregnant women regardless of the gestational age. However, EVs were significantly elevated in both EoPE (3.5-fold) and LoPE (1.5-fold) compared with matched controls. First-trimester EV levels did not show differences between women who later developed PE and normal controls. These findings indicate that CD9 is a promising marker for plasma-derived small EVs and that an elevated number of small EVs is associated with established PE but has limited predictive value in early pregnancy. Further studies are required to elucidate the cellular origin and clinical implications of small EVs in PE. Full article

Nanotechnology has emerged as a promising approach to enhance agricultural productivity; in this context, the effects of nanoparticles (NPs) on plants depend strongly on their size, composition, and concentration. We evaluated the influence of titanium dioxide (TiO₂) and silver-doped titanium dioxide (Ag-TiO₂) nanoparticles on seed germination, early growth, metabolite production, and antioxidant responses in alfalfa (Medicago sativa L.). Nanoparticles were synthetized via sol–gel; titanium isopropoxide was used as precursor and isopropanol as organic solvent, silver nitrate was used as dopant. Seeds were treated with nanoparticle suspensions at 0, 1, 5, 10, and 15 ppm. Morphological parameters (germination rate, radicle length, fresh weight, leaf morphology, and chlorophyll index), total phenols, flavonoids, and antioxidant capacity (DPPH and ABTS assays) were evaluated. Results showed a concentration-dependent response in morphological characteristics. TiO₂ promoted radicle elongation at 10 ppm (16%) and increased chlorophyll index along all concentrations (from 7% to 17%) but inhibited leaf growth at both 1 and 15 ppm (from 49% to 59%). In contrast, Ag-TiO₂ enhanced germination percentage by up to 95% and phenolic accumulation at 5 and 15 ppm (p < 0.05), although leaf length was consistently reduced across all concentrations (from 11% to 17%). Flavonoid levels increased by up to 116% at concentration of 15 ppm (p < 0.05). Antioxidant activity exhibited a contrasting pattern: TiO₂ reduced radical scavenging capacity when applied at 10 and 15 ppm, against the control group, from 48.62% to 17.72% and 13.96%, respectively, while Ag-TiO₂ maintained the antioxidant capacity when applied at 1 ppm. These findings suggest that nanoparticles in fact influence the germination process and have a noticeable effect on the morphological characteristics of alfalfa’ sprouts. Full article

Silver nanoparticles (AgNPs) are extensively utilized in cosmetics and healthcare products, creating an urgent need for sensitive quantification methods. We report the first application of a metal–organic framework for electrochemical AgNPs sensing in cosmetic samples. A glassy carbon electrode was modified with polyethyleneimine-encapsulated MOF-235 (PEI-MOF-235/GCE); the PEI layer enriches AgNPs through Ag–N coordination, whereas the high-surface-area MOF catalyzes their oxidative dissolution. Under optimized conditions (catalyst loading 1.4 µg mm⁻³, pH 4.3 PBS), differential-pulse voltammetry provided a linear range of 10–100 ng L⁻¹ and a detection limit of 3.93 ng L⁻¹ (S/N = 3). The sensor exhibited excellent stability (RSD ≤ 4.7%) and good anti-interference capability toward common aquatic ions. Compared with a standard HPLC method, recoveries in spiked cosmetic samples were 97.9–102.6%. This MOF-based strategy offers a sensitive, selective, and field-deployable platform for routine monitoring of trace AgNPs. Full article

Green silver nanoparticles (AgNPs) have been increasingly recognized for their antimicrobial properties and environmental compatibility. In this study, AgNPs were synthesized using an aqueous extract of Manacá-da-Serra (Pleroma sellowianum) flowers as a natural reducing and stabilizing agent and subsequently incorporated into a chitosan matrix to produce functionalized composites for industrial wastewater disinfection. Optimal synthesis conditions were achieved at pH 12.0, 25 °C, and 0.01 mol/L AgNO₃, yielding uniformly dispersed spherical NPs (20–30 nm) with moderate colloidal stability (zeta potential ≈ −14 mV) and a minimum inhibitory concentration of 5 μL/mL against Escherichia coli and Staphylococcus aureus. The effective integration of AgNPs into the biopolymer was verified by Fourier-transform infrared spectroscopy (FTIR), thermogravimetric analysis (TGA), transmission electron microscopy (TEM), and energy dispersive spectroscopy (EDS). The interaction between AgNPs and chitosan was confirmed by the data, while successful NP incorporation was further supported by homogeneous Ag distribution and improved thermal stability. Inhibition zones of 11 ± 1 mm (S. aureus) and 9 ± 1 mm (E. coli) were revealed by antimicrobial assays. For industrial wastewater disinfection, a total coliform reduction of >99.9% was achieved within 180 min, with Ag release remaining at 0.01 mg/L, below the regulatory threshold. The synergistic effect between chitosan and green-synthesized AgNPs was highlighted by these findings, demonstrating the potential of this environmentally friendly material for efficient, safe, and sustainable wastewater disinfection and reuse. Full article

The success of plant tissue cryopreservation strongly depends on maximizing explant survival during storage in liquid nitrogen and recovery, which requires species-specific protocol optimization and ongoing refinement. This study examined the effect of Plant Vitrification Solution 3 (PVS3) supplemented with nanoparticles (NPs) or melatonin (MEL) on the recovery of Lamprocapnos spectabilis (L.) Fukuhara explants after cryostorage. Treatments with ZnO + Ag NPs, as well as different MEL concentrations, were applied to evaluate their influence on explant survival, photosynthetic efficiency, and genetic stability. The highest recovery (40–44%) was obtained with PVS3 containing 50 mg L⁻¹ ZnO + 0.1% Ag NPs and PVS3 supplemented with 8 mg L⁻¹ MEL, which was 17.5–20% higher than in the control. These treatments, however, did not ensure the highest photosynthetic efficiency of recovered plants. PVS additives likely support recovery by slowing metabolism and reducing oxidative stress, with lower photosynthetic activity suggesting a lag phase in plastid regeneration. Using the Start Codon Targeted (SCoT) marker system, no significant genetic alterations were detected in recovered plants of any tested variant. These findings demonstrate the feasibility of optimizing cryopreservation protocols for L. spectabilis and encourage further research on combined NPs and MEL treatments or alternative nanocarriers. Full article

Gold (Au) and silver (Ag) nanoparticles (NPs) are used for drug transport and plant protection due to their insoluble nature and unique properties. To produce health-friendly NPs, toxic solvents should be replaced with plant-based synthesis. Plants, such as alfalfa (Medicago sativa L.), release biomolecules that reduce metal ions and form nanoclusters without free radicals, showing anti-inflammatory and antioxidant properties. In this study, callus cultures of two M. sativa genotypes, ‘Kometa’ and ‘La Bella Campagnola’, were exposed to two precursors (AgNO₃ and HAuCl₄) for 24 and 48 h to assess the feasibility of biological NP synthesis. Spectrophotometry showed significant (p ≤ 0.05) changes in light absorbance compared with the control. Dynamic light scattering and zeta potential measurements indicated a change in the composition of the liquid compared with the control. To improve image quality and obtain more accurate data, transmission electron microscopy (TEM) analysis was repeated, confirming the presence of quasi-spherical nanoparticles with diameters in the range of 5–25 nm for both AuNPs and AgNPs in the callus culture extracts of both genotypes. Nanoparticle Tracking Analysis demonstrated that the AgNPs and AuNPs from both genotypes displayed polydisperse size distributions, with a mean particle size ranging from 220 to 243 nm. Elemental analysis provided clear evidence that Ag and Au were present only in treated samples, confirming effective NP biosynthesis and excluding contamination. X-ray diffraction (XRD) analysis was performed to characterise the crystalline structure; however, due to the very small particle size (5–25 nm), no clear diffraction patterns could be obtained, as nanocrystals below ~20–30 nm typically produce signals below the detection limit of standard XRD instrumentation. The novelty of this research is the cost-effective, rapid biosynthesis of quasi-spherical AuNPs and AgNPs with diverse sizes and enhanced properties, making them more eco-friendly, less toxic, and suitable for antibacterial and anticancer studies. Full article

A comprehensive investigation was conducted focusing on two series of poly(lactic acid) (PLA)-based nanocomposites filled with small amounts (0.5 and 1.0%) of metal (Ag/Cu) nanoparticles (NPs). Our work aimed to synthesize PLA/Ag nanocomposites via in situ ring-opening polymerization (ROP), and for comparison purposes, the same materials were also prepared via solution casting followed by melt mixing. PLA/Cu nanocomposites were also prepared via melt extrusion. Gel permeation chromatography (GPC) and intrinsic viscosity measurements [η] showed that the incorporation of Ag nanoparticles (AgNPs) resulted in a decrease in the molecular weight of the PLA matrix, indicating a direct effect of the AgNPs on its macromolecular structure. Fourier-transform infrared spectroscopy (FTIR) revealed no significant changes in the characteristic peaks of the nanocomposites, except for an in situ sample containing 1.0 wt% of AgNPs, where slight interactions in the C=O region were detected. Differential scanning calorimetry (DSC) analysis confirmed the semi-crystalline nature of the materials. Glass transition temperature was strongly affected by the presence of NPs in the case of the in situ-based samples. Melt crystallized studies suggested potential indirect polymer–NP interactions, while isothermal melt crystallization experiments confirmed the nucleation ability of the NPs. The mechanical performance was assessed via tensile and flexural measurements, revealing that the in situ-based samples exhibited remarkable flexibility. Moreover, during the three-point bending tests, none of the in situ nanocomposite samples broke. In this context, next-generation PLA-based nanocomposites have been proposed for advanced applications, including flexible printed electronics. Full article

Recently, the state of the art of aerogels (AGs) has been reviewed, reporting first on their classification, based on the chemical origin of their precursors and the different methods existing to prepare them. Additionally, AGs of inorganic origin (IAGs) were contemplated, deeply discussing the properties, specific synthesis, and possible uses of silica and metal oxide-based AGs, since they are the most experimented and patented AGs already commercialized in several sectors. In this second part review, IAGs are examined again, but chalcogenide and metals AGs (CAGs and MAGs) are debated, since they are still too little studied, patented, and marketed, despite their nonpareil properties and vast range of possible applications. First, to give readers unaware of the previous work on AGs, a background about IAGs, all their main subclasses have been reported and their synthesis, including sol–gel, epoxide addition (EA), and dispersed inorganic (DIS) methods, as well as procedures involving the use of pre-synthesized nanoparticles as building blocks, have been discussed. Morphology and microstructure images of materials prepared by such synthetic method have been supplied. Conversely, the methods needed to prepare CAGs and MAGs, topics of this study, have been debated separately in the related sections, with illustrative SEM images. Their possible uses, properties, and some comparisons of their performance with that of other AGs and not AG materials traditionally tested for the same scopes, have also been disserted, reporting several case studies in reader-friendly tables. Full article

Silver nanoparticles (AgNPs) were synthesized using a modified literature method involving aqueous AgNO₃ (3 mM) and plant extract (LCE) at a constant ratio, under alkaline conditions and controlled temperature. The nanoparticles were characterized by UV-Vis spectroscopy, dynamic light scattering (DLS), zeta potential analysis and scanning transmission electron microscopy (STEM). The UV-Vis spectra displayed a broad absorption band around 450 nm, indicative of polydispersity, while DLS revealed a hydrodynamic diameter of 90.3 nm with a polydispersity index of 0.3366. Zeta potential values suggested reduced electrostatic stability compared with previously reported plant-derived AgNPs, although STEM images confirmed predominantly spherical, well-dispersed nanoparticles with sizes between 15 and 20 nm. Functional assays in zebrafish demonstrated the biological relevance of AgNPs. In scopolamine-induced models of cognitive and behavioral deficits, AgNPs treatment significantly improved memory and locomotor activity, as assessed by the Y-Maze, Novel Tank Diving Test and Novel Object Recognition Test. Full article

Current demands in the field of functional textiles include the integration of specific characteristics, such as self-cleaning, antimicrobial efficacy and possible wound healing properties. Green synthesis of nanoparticles represents a promising strategy to address these challenges, combining biocompatibility and ecological safety with effective antimicrobial and antioxidant performance. In this study, silver nanoparticles (AgNPs) have been synthesized using different ratios of Crataegus monogyna extract: AgNO₃. Physically stable AgNPs with spherical shape, particle main diameters ranging from 61.9 to 85.4 nm and appropriate polydispersity indices were produced. Crataegus monogyna presented high phenolic content (30.58 ± 2.20 mg/g) and strong antioxidant activity (96 ± 1.6 µmol TE/g). The obtained nanoparticles were characterized by TEM, EDX, and XRD analysis. When applied to cotton and wool textiles, the AgNPs adhered uniformly, caused minimal colour change, and exhibited enhanced antimicrobial activity against bacterial and fungal strains compared to other plant-derived AgNPs, with values between 8 and 13.5 mm. The treated textiles demonstrated strong performance against Staphylococcus aureus with inhibition zones of 11 ± 0.53 for cotton and 13.5 ± 0.42 for wool. These findings highlight the potential of Crataegus monogyna-based AgNPs as effective and fabric-compatible antimicrobial agents. Full article

This paper presents the synthesis of sustainable lignin nanoparticles (LNPs) and their application in methylcellulose (MC) as LNP/MC coatings for handmade papers. LNPs were produced from bulk kraft lignin via an acetone/water and sonication method, then incorporated into a 1 wt% methylcellulose (MC) matrix at concentrations of 0.4, 1, and 2 wt%. Groundwood and cotton linter papers were coated and exposed to 90 °C and 45% relative humidity (RH) for 16 days and the samples’ response to ageing at different concentrations of nanolignin was tested using a multi-analytical approach. The morphology of the LNPs was revealed with scanning electron microscopy, and most LNPs measured below a diameter of 30.8 nm. Colourimetry showed coated samples were inherently darker than uncoated samples but mostly stable in colour. pH remained near neutral for coated groundwood papers during ageing, but cotton papers were consistently acidic. Fourier transform infrared (FTIR) spectroscopy identified spectral similarities between uncoated and coated groundwood samples at approximately 1635 cm^–1 and 1725 cm^–1, attributed to carbonyl and carboxyl groups, suggesting that LNPs did not contribute to the formation of these groups during ageing. Controlled environment dynamic mechanical analysis (DMA-RH) found improved consolidation and lower elongation in most LNP/MC-treated samples. These results indicate that there may be potential for LNPs within paper conservation. Full article