Search Results (9,885)

This study examined the eco-friendly synthesis of zinc oxide (ZnO) nanoparticles using Cladophora glomerata extracts as reducing and stabilizing agents, comparing zinc acetate and zinc chloride precursors for biomedical and environmental applications. Zinc acetate-synthesized ZnO nanoparticles showed a significant absorption peak around 320–330 nm, indicating stable, quasi-spherical ZnO nanoparticles with a narrow size distribution, primarily around 100 nm. Zeta potential measurements revealed a value of −25 mV for these particles, suggesting moderate colloidal stability. XRD analysis confirmed a highly crystalline hexagonal wurtzite structure for zinc acetate-derived ZnO, and SEM images supported a proper microstructure with approximately 2 µm particle size. FTIR analysis indicated higher-quality ZnO from zinc acetate due to the absence of moisture and hydroxyl groups. Conversely, zinc chloride-derived ZnO particles displayed a broader absorption spectrum around 370 nm, indicative of significant aggregation. Their narrower zeta potential distribution around +10 mV suggested diminished colloidal stability and a heightened aggregation tendency. While a peak around 100 nm was observed, many particles exceeded 1000 nm, reaching up to 10,000 nm. XRD results showed that zinc chloride adversely affected crystallinity, and SEM analysis indicated smaller particles (approx. 1 µm). FTIR analysis demonstrated that zinc chloride samples retained hydroxyl groups. Both zinc acetate- and zinc chloride-derived ZnO nanoparticles produced notable inhibitory zones against Gram-positive (L. monocytogenes, S. aureus) and specific Gram-negative bacteria (E. coli, K. pneumoniae). Zinc acetate-derived ZnO showed a 21 mm inhibitory zone against P. vulgaris, while zinc chloride-derived ZnO showed a 10.1 mm inhibitory zone against C. albicans. Notably, zinc chloride-derived ZnO exhibited broad-spectrum antimicrobial activity. MIC readings indicated that zinc acetate-derived ZnO had better antibacterial properties at lower concentrations, such as 3.125 µg/mL against L. monocytogenes. These findings emphasize that the precursor material selection critically influences particle characteristics, including optical properties, surface charge, and colloidal stability. Full article

Biocompatible vaterite microspheres, renowned for their porous structure, are promising carriers for magnetic nanoparticles (MNPs) in biomedical applications such as targeted drug delivery and diagnostic imaging. Precise control over the magnetic moment of individual microspheres is crucial for these applications. This study employs widefield quantum diamond microscopy to map the stray magnetic fields of individual vaterite microspheres (3–10 μm) loaded with Fe₃O₄ MNPs of varying sizes (5 nm, 10 nm, and 20 nm). By analyzing over 35 microspheres under a 222 mT external magnetizing field, we measured peak-to-peak stray field amplitudes of 41 ± 1 μT for 5 nm and 10 nm superparamagnetic MNPs, reflecting their comparable magnetic response, and 12 ± 1 μT for 20 nm ferrimagnetic MNPs, due to distinct magnetization behavior. Finite-element simulations confirm variations in MNP distribution and magnetization uniformity within the vaterite matrix, with each microsphere encapsulating thousands of MNPs to generate its magnetization. This high-resolution magnetic imaging approach yields critical insights into MNP-loaded vaterite, enabling optimized synthesis and magnetically controlled systems for precision therapies and diagnostics. Full article

Selenium nanoparticles (SeNPs), with their high absorption and antioxidant properties, hold promise as feed additives in aquaculture, enhancing growth and reproductive health in fish. This review evaluates how selenium nanoparticles influence growth and reproductive traits in Asian seabass (L. calcarifer). Using the PRISMA approach, we examined the impacts of selenium nanoparticles (SeNPs) on the growth performance and gonadal development of Asian seabass (L. calcarifer) by synthesizing findings from the existing literature. Meta-analysis explored that selenium nanoparticles (SeNPs) supplementation significantly improved specific growth rate (SGR) (pooled effect size = 3.97; 95% CI: 3.68–4.26) and feed conversion ratio (FCR) (pooled effect size = 0.81; 95% CI: 0.75–0.86), with low heterogeneity. Regarding reproductive outcomes, SeNPs enhanced gonadal development, sperm quality, and steroidogenesis. Significant improvements were observed in gonadosomatic index (effect size = 0.5), fertilization rate (0.6), and testosterone levels (0.5), along with a reduction in abnormal embryogenesis (−0.3) (p < 0.05). While an optimal level of SeNPs is effective for enhancing aquaculture performance, excessive use may lead to toxicity; therefore, their economic viability, environmental impact, and sustainability in large-scale aquaculture warrant further investigation. This review provides insights for researchers, policymakers, and industry stakeholders on the potential of SeNPs in advancing sustainable aquaculture through fish productivity and reproductive performance. Full article

Prostate cancer is a serious, life-threatening condition among men, usually requiring long-term chemotherapy. Due to its high efficacy, bicalutamide, a non-steroidal anti-androgen, has widespread use. However, its poor water solubility, low oral bioavailability, and nonspecific systemic exposure limit its application. To overcome these obstacles, our study explored the potential of non-carboxylated and carboxylated mesoporous carbon nanoparticles (MCN) as advanced drug carriers for bicalutamide (MCN/B and MCN-COOH/B). The physicochemical properties and release behaviour were thoroughly characterized. Functionalization with carboxylic groups significantly improved wettability, dispersion stability, as well as loading efficiency due to enhanced hydrogen bonding and π–π stacking interactions. Moreover, all systems exhibited sustained and near-infrared (NIR) triggered drug release with reduced burst-effect, compared to the release of free bicalutamide. Higher particle size and stronger drug–carrier interactions determined a zero-order kinetics and notably slower release rate of MCN-COOH/B compared to non-functionalized MCN. Cytotoxicity assays on LNCaP prostate cancer cells demonstrated that both MCN/B and MCN-COOH/B possessed comparable antiproliferative activity as free bicalutamide, where MCN-COOH/B exhibited superior efficacy, especially under NIR exposure. These findings suggest that MCN-COOH nanoparticles could be considered as a prospective platform for controlled, NIR-accelerated delivery of bicalutamide in prostate cancer treatment. Full article

Marine algae offer environmentally friendly platforms for green nanoparticle synthesis. This study reports the biosynthesis of silver nanoparticles using polysaccharides isolated from the brown alga Chnoospora minima (PAgNPs) and evaluates their therapeutic potential. Fourier Transform Infrared Spectroscopy (FTIR) confirmed algal polysaccharide functional groups. Dynamic Light Scattering (DLS), Scanning Electron Microscopy (SEM), and Energy Dispersive X-ray (EDX) analysis characterized the nanoparticles as spherical (~84 nm average size), stable (zeta potential −18.5 mV), and containing elemental silver without nitrogen. The PAgNPs exhibited potent antioxidant activity (~100% DPPH scavenging) and significant antimicrobial efficacy, particularly against Staphylococcus aureus and Candida species. Crucially, PAgNPs displayed potent antiproliferative activity against human lung cancer cells (A549, IC₅₀: 13.59 µg/mL). In contrast, toxicity to normal Vero cells was significantly lower (IC₅₀: 300.2 µg/mL), demonstrating notable cancer cell selectivity (SI 22.1). Moderate activity was observed against MCF-7 breast cancer cells (IC₅₀: 100.7 µg/mL). These results demonstrate that C. minima polysaccharide facilitates the synthesis of biocompatible AgNPs with promising antimicrobial and selective anticancer capabilities, highlighting their potential for further development as nanotherapeutics. Full article

This study investigates the antioxidant, antimicrobial, and antitumor activities of Taraxacum officinale (Dandelion) and Artemisia annua (Sweet Wormwood) extracts, along with their role in the green synthesis of gold (AuNPs) and silver nanoparticles (AgNPs). Bioreduction was achieved using aqueous and ethanolic extracts (100 mg/mL), enabling solvent-dependent comparisons. Nanoparticles were characterized using ultraviolet–visible spectroscopy (UV–Vis), fluorescence spectroscopy, scanning electron microscopy (SEM), dynamic light scattering (DLS), high-resolution transmission electron microscopy (HRTEM), and zeta potential analysis. Each technique revealed complementary aspects of nanoparticle morphology, size, and stability, with UV–Vis indicating aggregation states and DLS confirming solvent-related size variation even at 3–5% ethanol. Gold nanoparticles synthesized from Dandelion showed strong antibacterial activity against Staphylococcus aureus, while silver nanoparticles from both plants were effective against Escherichia coli. Cytotoxicity assays indicated that silver nanoparticles obtained from ethanolic Dandelion extract containing 3% ethanol in aqueous solution (AgNPsE_ETOH3%-D) significantly reduced LoVo (p = 4.58 × 10⁻³) and MDA-MB-231 (p = 7.20 × 10⁻⁵) cell viability, with high selectivity indices (SI), suggesting low toxicity toward normal cells. Gold nanoparticles synthesized from aqueous Dandelion extract (AuNPsEaq-D) also showed favorable SI values (2.16 for LoVo and 8.41 for MDA-MB-231). Although some formulations demonstrated lower selectivity (SI < 1.5), the findings support the therapeutic potential of these biogenic nanoparticles. Further in vivo studies and pharmacokinetic evaluations are required to validate their clinical applicability. Full article

The development of non-noble metal catalysts for gas-phase propylene epoxidation with H₂/O₂ remains challenging due to their inadequate activity and stability. Herein, we report a Cs⁺-modified Ni/TS-1 catalyst (9%Ni-Cs/TS-1), which exhibits unprecedented catalytic performance, giving a state-of-the-art PO formation rate of 382.9 g_PO·kg_cat⁻¹·h⁻¹ with 87.8% selectivity at 200 °C. The catalyst stability was sustainable for 150 h, far surpassing reported Ni-based catalysts. Ni/TS-1 exhibited low catalytic activity. However, the Cs modification significantly enhanced the performance of Ni/TS-1. Furthermore, the intrinsic reason for the enhanced performance was elucidated by multiple techniques such as XPS, N₂ physisorption, TEM, ²⁹Si NMR, NH₃-TPD-MS, UV–vis, and so on. The findings indicated that the incorporation of Cs⁺ markedly boosted the reduction of Ni, enhanced Ni⁰ formation, strengthened Ni-Ti interactions, reduced acid sites to inhibit PO isomerization, improved the dispersion of Ni nanoparticles, reduced particle size, and improved the hydrophobicity of Ni/TS-1 to facilitate propylene adsorption/PO desorption. The 9%Ni-Cs/TS-1 catalyst demonstrated exceptional performance characterized by a low cost, high activity, and long-term stability, offering a viable alternative to Au-based systems. Full article

A ceramic–metal composite was synthesized using sol–gel and electrospinning methods to serve as a SERS substrate. The precursors used were tetraethyl orthosilicate, aluminum nitrate, and zirconium, and polyvinylpyrrolidone was added to electrospun nonwoven fibrous membranes. The membranes were sintered, decorated with silver nanoparticles. The enhancement substrates were made of fibers of cylindric morphology with an average diameter of approximately 190 nm, a smooth surface, and 9 nm spherical particles decorating the surface of the fibers. The enhancement capacity of the substrates was tested using pyridine, methyl orange, methylene blue, crystal violet, and Eriochrome black T at different concentrations with Raman spectroscopy to determine whether the size and complexity of the analyte has an impact on the enhancement capacity. Enhancement factors of 2.53 × 10², 3.06 × 10¹, 2.97 × 10³, 4.66 × 10³, and 1.45 × 10³ times were obtained for the signal of pyridine, methyl orange, methylene blue, crystal violet, and Eriochrome black T at concentrations of 1 nM. Full article

Background/Objectives: Chemotherapy-induced alopecia is a common and distressing side effect of cancer treatment, significantly impacting patients’ psychological well-being. Nanocarriers offer a promising strategy for targeted drug delivery to hair follicles, while chitosan nanoparticles have demonstrated hair-growth-promoting properties. This study explores the potential of chitosan nanoparticles as a topical delivery system for five pharmacological agents—phenobarbital, pioglitazone, rifampicin, N-acetylcysteine, and tacrolimus—to prevent chemotherapy-induced alopecia. Methods: Drug-loaded chitosan nanoparticles were prepared using the ionic gelation technique and characterized by particle size, zeta potential, entrapment efficiency, FT-IR spectroscopy, and TEM imaging. Their efficacy was assessed in a cyclophosphamide-induced alopecia model in C57BL/6 mice through macroscopic observation, histopathological examination, and scanning electron microscopy of regrown hair. Results: The prepared particles were spherical, cationic, and between 205 and 536 nm in size. The entrapment efficiencies ranged from 8% to 63%. All five drugs mitigated follicular dystrophy, shifting the hair follicle response from dystrophic catagen to dystrophic anagen. Phenobarbital demonstrated the most significant hair regrowth and quality improvements, followed by N-acetyl cysteine and pioglitazone. Tacrolimus showed moderate efficacy, while rifampicin was the least effective. Conclusions: These findings suggest that phenobarbital-loaded chitosan nanoparticles represent a promising approach for the prevention and treatment of chemotherapy-induced alopecia, warranting further investigation for clinical applications. Full article

Achieving targeted nanoparticle (NP) size and concentration combinations in Pulsed Laser Ablation in Liquid (PLAL) remains a challenge due to the highly nonlinear relationships between laser processing parameters and NP properties. Despite the promise of PLAL as a surfactant-free, scalable synthesis method, its industrial adoption is hindered by empirical trial-and-error approaches and the lack of predictive tools. The current literature offers limited application of machine learning (ML), particularly recommender systems, in PLAL optimization and automation. This study addresses this gap by introducing a ML-based recommender system trained on a 3 × 3 design of experiments with three replicates covering variables, such as fluence (1.83–1.91 J/cm²), ablation time (5–25 min), and laser scan speed (3000–3500 mm/s), in producing magnesium nanoparticles from powders. Multiple ML models were evaluated, including K-Nearest Neighbors (KNN), Extreme Gradient Boosting (XGBoost), Random Forest, and Decision trees. The DT model achieved the best performance for predicting the NP size with a mean percentage error (MPE) of 10%. The XGBoost model was optimal for predicting the NP concentration attaining a competitive MPE of 2%. KNN and Cosine similarity recommender systems were developed based on a database generated by the ML predictions. This intelligent, data-driven framework demonstrates the potential of ML-guided PLAL for scalable, precise NP fabrication in industrial applications. Full article

This work explores zinc oxide nanoparticle (ZnO NP) synthesis utilizing leaf extract of the Gaultheria fragrantissima plant that are useful in medicine, environmental remediation, and cosmetics due to their antibacterial activity, photocatalytic efficiency, and UV-blocking characteristics. Traditional synthesis methods involve energy-intensive procedures and hazardous chemicals, posing environmental and human health risks. To overcome these limitations, this research focuses on utilizing G. fragrantissima, rich in bioactive compounds such as phenolics and flavonoids, with the methyl salicylate previously reported in the literature for this species, which helps reduce and stabilize NPs. ZnO NPs were characterized through X-ray diffraction (XRD), UV–visible spectroscopy, Fourier transform infrared (FTIR) spectroscopy, field emission scanning electron microscopy (FESEM), and energy-dispersive spectroscopy (EDS). The ZnO NPs were found to have a well-defined crystalline structure, with their average crystallite size measured at around 8.26 nm. ZnO NPs exhibited moderate antimicrobial activity against selected microbial strains. These findings underscore the potential of G. fragrantissima-mediated synthesis as an environmentally sustainable and efficient method for producing ZnO NPs with multifunctional applications. This study provides a greener alternative to conventional synthesis approaches, demonstrating a method that is both eco-friendly and capable of yielding NPss with desirable properties. Full article

Exosomes, small extracellular vesicles secreted by various cell types, have gained significant attention in cancer investigations. Isolation and characterization of exosomes derived from DOK (dysplastic oral keratinocyte), SCC (squamous cell carcinoma) and HaCaT (normal skin keratinocyte) cell lines and microRNA profiling were conducted. Magnetic sorting was applied to obtain pure exosomes. Morphology and size were characterized by transmission electron microscopy and nanoparticle tracking analysis. Validation of membrane exosomal markers (CD9, CD63) was performed via Western blotting. MiR-21, miR-31, and miR-133 levels were analyzed in exosomes and parent cells by qPCR. Biological effects of the exosomes were tested by adding them to fibroblast cultures and determining the expression of relevant carcinogenesis markers by qPCR. Exosomes appeared as cup-shaped nano-sized particles, and there was no difference regarding particle diameter and concentration between the three types of exosomes. The oncogenic miR-21 was significantly upregulated both in SCC and SCC-derived exosomes compared to DOK and HaCaT cells and their respective exosomes. However, miR-31 unexpectedly showed the highest expression in normal cells and the lowest in HaCaT exosomes. MiR-133, the tumor suppressor miRNA, was downregulated in both SCC and DOK cells compared to normal (HaCaT) cells, while the opposite situation was observed in exosomes, with HaCaT cells showing the lowest levels of miR-133. The differences in exosome content were reflected in signaling pathway activation in exosome-treated fibroblasts, with SCC exosomes exerting the most potent effect on several cancer-related pathways, notably PIK3/AKT, PTEN, and NOTCH signaling cascades. Full article

PAMAM dendrimers are distinguished by their capacity for functionalization, which enhances the properties of the compounds they transport, rendering them highly versatile nanoparticles with extensive applications in the biomedical domain, including drug, vaccine, and gene delivery. These dendrimers can be internalized into cells through various endocytic mechanisms, such as passive diffusion, clathrin-mediated endocytosis, and caveolae-mediated endocytosis, allowing them to traverse the cytoplasm and reach intracellular targets, such as the mitochondria or nucleus. Despite the significant challenge posed by the cytotoxicity of these nanoparticles, which is contingent upon the dendrimer size, surface charge, and generation, numerous strategies have been documented to modify the dendrimer surface using polyethylene glycol and other chemical groups to temporarily mitigate their cytotoxic effects. The potential of PAMAM dendrimers in cancer therapy and other biomedical applications is substantial, owing to their ability to enhance bioavailability, pharmacokinetics, and pharmacodynamics of active ingredients within the body. This underscores the necessity for further investigation into the optimization of internalization pathways and cytotoxicity of these nanoparticles. This review offers a comprehensive synthesis of the current literature on the diverse cellular internalization pathways of PAMAM dendrimers and their cargo molecules, emphasizing the mechanisms of entry, intracellular trafficking, and factors influencing these processes. Full article

In the present study, novel conjugated lignin/chitosan nanoparticles (LCNPs) were synthesized by a first-time simple green methodology using interfacial co-assembly between both biopolymers. The physicochemical (ζ-potential, size, concentration of surface acidic/basic groups), structural (surface functional groups), and morphological characteristics of the blank and quercetin-encapsulated (Q-LCNPs) nanoparticles were analyzed by the Boehm method, Fourier-transform infrared spectroscopy (FTIR), transmission electron microscopy (TEM), and X-ray diffraction (XRD). The experimentally determined encapsulation capacity was satisfactory—95.75%. The in vitro quercetin release efficiency in acidic solution that simulated the gastric microenvironment was 21.9%, followed by 68.5% and 99.8% cumulative release efficiency in simulated intestinal media at pH 7.4 and 6.8, respectively. The satisfactory applicability of the Weibull and sigmoidal mathematical models towards the experimental in vitro release data was indicative of the remarkable roles of diffusion and relaxation mechanisms. Full article

Ag-doped ZnO is a promising photocatalyst. However, the combined influence of the Ag doping concentration and furnace temperature has not been adequately explored, hindering the optimization of ZnO/Ag materials for practical applications. In this study, ZnO/Ag materials were synthesized via ultrasonic spray pyrolysis by systematically varying both the furnace calcination temperature and the Ag doping concentration. The synthesized materials were analyzed through a range of spectroscopic methods to investigate their structural, morphological, and surface characteristics. Their photocatalytic activity was assessed by monitoring the degradation of methylene blue (MB) under ultraviolet light exposure. The findings indicate that the ZnO sample that was calcined at 400 °C exhibited the highest degradation efficiency among the undoped samples, which can be attributed to its submicron particle size, moderate crystallinity, and high surface hydroxylation. The sample with 5-wt% Ag doping achieved enhanced performance, demonstrating the best photocatalytic activity (65% MB degradation). This improvement was attributed to the synergistic effects of surface plasmon resonance and optimized interaction between the Ag nanoparticles and surface hydroxyl groups. Excessive Ag loading (10 wt%) led to reduced activity owing to potential agglomeration and recombination centers. These results highlight the critical role of both the thermal and chemical parameters in tailoring ZnO-based photocatalysts for wastewater treatment applications. Full article