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The development of a colloidal synthesis procedure to produce nanomaterials with high shape and size purity is often a time-consuming, iterative process. This is often due to quantitative uncertainties in the required reaction conditions and the time, resources, and expertise intensive characterization methods required for quantitative determination of nanomaterial size and shape. Absorption spectroscopy is often the easiest method for colloidal nanomaterial characterization. However, due to the lack of a reliable method to extract nanoparticle shapes from absorption spectroscopy, it is generally treated as a more qualitative measure for metal nanoparticles. This work demonstrates a gold nanorod (AuNR) spectral morphology analysis tool, called AuNR-SMA, which is a fast and accurate method to extract quantitative structural information from colloidal AuNR absorption spectra. To demonstrate the practical utility of this model, we apply it to three distinct applications. First, we demonstrate this model's utility as an automated analysis tool in a high-throughput AuNR synthesis procedure by generating quantitative size information from optical spectra. Second, we use the predictions generated by this model to train a machine learning model to predict the resulting AuNR size distributions under specified reaction conditions. Third, we apply this model to spectra extracted from the literature where no size distributions are reported and impute unreported quantitative information on AuNR synthesis. This approach can potentially be extended to any other nanocrystal system where absorption spectra are size dependent, and accurate numerical simulation of absorption spectra is possible. In addition, this pipeline could be integrated into automated synthesis apparatuses to provide interpretable data from simple measurements, help explore the synthesis science of nanoparticles in a rational manner, or facilitate closed-loop workflows.

Many applications of plasmonic nanoparticles require precise control of their optical properties that are governed by nanoparticle dimensions, shape, morphology and composition. Finding reaction conditions for the synthesis of nanoparticles with targeted characteristics is a time-consuming and resource-intensive trial-and-error process, however closed-loop nanoparticle synthesis enables the accelerated exploration of large chemical spaces without human intervention. Here, we introduce the Autonomous Fluidic Identification and Optimization Nanochemistry (AFION) self-driving lab that integrates a microfluidic reactor, in-flow spectroscopic nanoparticle characterization, and machine learning for the exploration and optimization of the multidimensional chemical space for the photochemical synthesis of plasmonic nanoparticles. By targeting spectroscopic nanoparticle properties, the AFION lab identifies reaction conditions for the synthesis of different types of nanoparticles with designated shapes, morphologies, and compositions. Data analysis provides insight into the role of reaction conditions for the synthesis of the targeted nanoparticle type. This work shows that the AFION lab is an effective exploration platform for on-demand synthesis of plasmonic nanoparticles. The automated synthesis of plasmonic nanoparticles with on-demand properties is a challenging task. Here the authors integrate a fluidic reactor, real-time characterization, and machine learning in a self-driven lab for the photochemical synthesis of nanoparticles with targeted properties. [ABSTRACT FROM AUTHOR]

AbstractThe green synthesis of metal nanoparticles (NPs) using plant extract is particularly irresistible technique. This study utilizes hydroalcoholic Endocomia macrocoma leaf extract to fabricate bismuth NPs (BiNPs). The synthesized BiNPs were characterized by UV–visible spectroscopy to assess its optical activities, FTIR analysis identified the functional groups in plant extract, and the synthesis of BiNPs. X-ray diffraction (XRD) gives the crystalline nature of the NPs. Dynamic light scattering (DLS) of the NPs shows an average size of 99.1 nm and 21.34 mV zeta potential of the NPs. Scanning electron microscopy (SEM) with energy dispersive X-ray spectroscopy (EDS) confirms the size and composition of the synthesized NPs, spherical shape of the NPs with size ranges 30–60 nm confirmed by transmission electron microscope (TEM). BiNPs were assessed the thermal stability by thermogravimetric (TG) analysis and differential scanning calorimetry (DSC) analysis for temperature and endothermic or exothermic processes, respectively. BiNPs showed good antibacterial activity against E. coli, P. aeruginosa, B. subtilis, and B. cereus with minimum inhibitory concentration (MIC) value of 250 µg/mL. Also, they exhibited antioxidant activity against 2,2-diphenyl-1-picrylhydrazyl (DPPH) with IC50 values of 125 µg/mL. The 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay showed that BiNPs have effective potential anticancer properties against human pancreatic (PANC2) and esophagus (KYSE-30) cancer cell lines with IC50 values of 48.31 and 66.94 µg/mL, respectively. Anti-reactive oxygen species (Anti-ROS) analysis clearly shows 89% cell viability of the NPs. Consequently, our results imply that BiNPs derived from E. macrocoma may be better natural therapy than chemical-based sources for medicinal purposes. [ABSTRACT FROM AUTHOR]

This study investigated the impact of a 10 kHz amplitude-modulation (AM) wave from a semiconductor microwave generator on the heating of ultrapure water and electrolyte aqueous solutions containing NaCl. It also examined the effects of AM waves on the yields of 4-methylbiphenyl (4-MBP) in the heterogeneous Suzuki–Miyaura coupling reaction, which was conducted in the presence of palladium nanoparticles supported on activated carbon (Pd/AC), as well as their influence on the growth rate during silver nanoparticle synthesis. Applying AM waves, typically used in telecommunications, enhanced heating efficiencies and improved product yields in both the chemical reaction and nanoparticle growth. Irradiating with microwaves under AM conditions allowed it to reduce power output while still achieving target yields and growth rates, even at the same temperatures without AM. This indicates the potential for highly efficient and energy-saving microwave processes in chemical reactions and material synthesis. [ABSTRACT FROM AUTHOR]

Green synthesis of metal oxides has attracted attention as the latest technology in synthesizing metal oxide nanoparticles due to its simplicity, cheapness, non-toxicity and its ability for large scale production. Metal oxides find applications in dye sensitized solar cells (DSSCs) as counter electrodes (CEs) and photo-anodes. However, applications of green synthesized metal oxides as counter electrodes have not been fully explored. In this study, CuO nanoparticles (NPs) were synthesized from Cucurbita maxima leaf extract and applied as a CE in DSSC. Uniformly synthesized CuO NPs were subjected to various characterization tools to obtain the crystal structure, surface morphology, particle size, optical properties, chemical bonds and photovoltaic properties. Using a natural dye from of Cucurbita maxima as a photon absorber, a short circuit current density (Jsc) of 4.2 μA/cm², open circuit voltage (Voc) of 0.17 V, a maximum power (Pmax) of 0.18 mW/cm², and a power conversion efficiency (PCE) of 1.8 × 10-4 % under one-sun illumination were obtained. [ABSTRACT FROM AUTHOR]

The widespread use of synthetic polymers in various industries has raised worldwide concerns regarding their ecological impact and effects on human health. As a result, biopolymers have emerged as a promising alternative. Among them, exopolysaccharides (EPSs) produced by microbes from terrestrial niches have been extensively studied. However, recent reports have indicated that microbes from marine environments can also produce unique EPSs that could serve as sustainable substitutes to meet the escalating demand for biopolymers. The present study, for the first time, reports EPS production from novel marine bacterium Algoriphagus sp. K5R for sustainable application development. Interestingly, physicochemical analyses suggest that EPS K5R is a high molecular weight (1190.63 kDa) heteropolysaccharide composed of galacturonic acid, glucose and mannose. To evaluate EPS production, growth and fermentation kinetics were performed, which revealed that it was a primary metabolite having a maximum production of 4.79 ± 0.57 g L−1 with 2% (w/v) glucose. Moreover, EPS K5R exhibits exceptional functional properties, namely high water‐holding capacity (720% ± 80.29%) and oil‐holding capacity (493.33% ± 49.74% for coconut oil and 533.32% ± 17.47% for olive oil), and non‐Newtonian pseudo‐plastic behavior which render it a promising candidate for application in the cosmetics and food industries. In fact, its anti‐oxidant capabilities make it an ideal biological reducing agent for metal nanoparticle synthesis. Overall, this study highlights the potential of marine EPSs for a diverse array of industrial applications. © 2024 Society of Chemical Industry. [ABSTRACT FROM AUTHOR]

Ag2O nanoparticle synthesis was carried out via co-precipitation technique based on using AgNO3 and secondary metabolites present in the aqueous extract of Opuntia humifusa fruit for the first time. The amount of measured total phenol, flavonoid content, flavone, and flavonol content, and anthocyanin were 38.46 μg eq gallic acid mg−1 extract, 8.34 μg eq quercetin mg−1 extract, 0.614 μg eq quercetin mg−1 DW, and 3.1 mmol L−1, respectively. Moreover, the predominant phenolic compound was gallic acid. Catechin and chlorogenic acid were found in both fruit juice and fruit aqueous extract. Scanning electron microscopy (SEM) of Ag2O-NPs showed the average particle size was 10.58 nm. Scanning electron microscopy, X-ray diffraction Spectroscopy, and UV/visible spectrometry also confirmed the synthesis. This study then focuses on IC50 and NO amount differences before and after the synthesis of Ag2O-NPs which were 448.29 and 101.38 μg mL−1 for IC50 and 35.7% and 62.6% for NO, respectively. [ABSTRACT FROM AUTHOR]

Microorganisms are becoming resistant to drugs and antimicrobials, making it a significantly critical global issue. Nosocomial infections are resulting in alarmingly increasing rates of morbidity and mortality. Plant derived compounds hold numerous antimicrobial properties, making them a very capable source to counteract resistant microbial strains. Syzygium aromaticum (Clove) extract has been proven by studies to contain active ingredients that demonstrate antibacterial, antifungal, antioxidant, and insecticidal properties. It has also been used historically for its pain relief especially for tooth ache. Clove extract derived nanoparticle synthesis is a promising method of combining therapeutics with metals at nanoscale. Such nanostructured systems in combination with the heterocyclic antibiotic clarithromycin could potentiate the action of plant extracts, decrease drug side effects and improve antimicrobial activity. In this study, clove extract (C) was successfully used to synthesize silver nanoparticles (AgNP) to create AgNPC and AgNPCA (A = clarithromycin). The two compounds underwent different analytical methods consisting of SEM, EDS, DLS, UV-vis, FTIR and XRD. These nanoparticles were used against a variety of 10 pathogens and exhibited very good to intermediate antibacterial properties. AgNPC resulted in better antibacterial properties and smaller nanoparticle size. This study demonstrates the potential of clove extract mediated AgNP synthesis in combination with and without the antibiotic clarithromycin. [ABSTRACT FROM AUTHOR]

In this study, we developed a facile one-pot synthesis of a nanocomposite consisting of silver nanoparticles (AgNPs) growing over graphene oxide (GO) nanoflakes (AgNPs@GO). The process consists of the in situ formation of AgNPs in the presence of GO nanosheets via the spontaneous decomposition of silver(I) acetylacetonate (Ag(acac)) after dissolution in water. This protocol is compared to an ex situ approach where AgNPs are added to a waterborne GO nanosheet suspension to account for any attractive interaction between preformed nanomaterials. The systems under investigation are characterized by UV/vis absorption spectroscopy, dynamic light scattering (DLS), zeta potential (Z-Pot), and scanning electron microscopy with energy-dispersive X-ray spectroscopy (SEM-EDX). The stability of the AgNPs@GO composite suspension is tested as a function of GO concentration (0–67 μg/mL) while maintaining a constant Ag content (14.4 μg/mL), exhibiting excellent stability over time up to an Ag-to-GO mass ratio of 0.58. [ABSTRACT FROM AUTHOR]

One of the methods for obtaining zinc oxide nanoparticles (ZnO NPs) is electrochemical synthesis. In this study, the anodic dissolution process of metallic zinc in alcohol solutions of LiCl was used to synthesize ZnO NPs. The products were obtained as colloidal suspensions in an electrolyte solution. Due to the small size and ionic nature of the zinc oxide molecule, colloidal nanoparticles tend to cluster into larger groupings, so the size of nanoparticles in solutions will differ from the size of nanoparticles observed in ZnO powders after solvent evaporation. The main goal of this research is to investigate the influence of the temperature of synthesis and the kind of alcohol on the size of ZnO NP micelles. Nanocrystals of zinc oxide were obtained in all tested alcohols: methanol, ethanol, and 1-propanol. The particle size was determined using the Dynamic Light Scattering (DLS) method. It was observed that the particles synthesized in methanol were the largest, followed by smaller particles in ethanol, while the smallest particles were obtained in 1-propanol. Additionally, the particles obtained in ethanol were the most uniform in size, showing the highest level of size homogeneity. [ABSTRACT FROM AUTHOR]

Abstract\nNOVELTY STATEMENTThis study introduces a sustainable biological approach for synthesizing silver nanoparticles (AgNPs) using Conocarpus seeds, aimed at improving the adsorption and photocatalytic degradation of methylene blue (MB) in wastewater treatment. The photocatalytic efficiency of AgNPs, synthesized under varying concentrations of silver nitrate (AgNO3) and pH levels, was evaluated, together with the effectiveness of a photocatalytic reactor. The synthesized samples were characterized using scanning electron microscopy (SEM), thermogravimetric analysis (TGA), Fourier-transform infrared (FT–IR) spectroscopy, and atomic force microscopy (AFM). Results showed that MB degradation occurred quickly within the first 50 min, achieving a 99.60% removal efficiency via adsorption and photocatalytic degradation under optimal conditions (pH = 3, 1 g sample) after 1 h. The maximum adsorption capacity reached 49.80 mg·g−1. Furthermore, the AgNPs demonstrated a significant degradation rate of 99.76% within 2 h under UV light, highlighting the synergistic effects of AgNPs in enhancing both adsorption and photocatalysis. This study not only accentuates the potential of Conocarpus seeds as an eco-friendly precursor for AgNP synthesis but also highlights the applicability of AgNPs in wastewater treatment.This study introduces a pioneering approach to synthesizing silver nanoparticles (AgNPs) using Conocarpus seeds as a natural biomass precursor, marking the first application of these AgNPs in the photocatalytic degradation of water dye pollutants. By demonstrating an eco-friendly and sustainable method for nanoparticle synthesis, this research not only enhances the photocatalytic efficiency of AgNPs but also affords a novel pathway for treating dye-contaminated wastewater, thereby substantially contributing to the existing literature on sustainable environmental remediation techniques. [ABSTRACT FROM AUTHOR]

Background: The healthcare sector faces a growing threat from the rise of highly resistant microorganisms, particularly Methicillin-resistant Staphylococcus aureus (MRSA) and multidrug-resistant Pseudomonas aeruginosa (MDR P. aeruginosa). Facing the challenge of antibiotic resistance, nanoparticles have surfaced as promising substitutes for antimicrobial therapy. Recent studies showcase the effectiveness of various fungi species in nanoparticle synthesis. Mycosynthesized silver nanoparticles (AgNPs) and selenium nanoparticles (SeNPs) using Aspergillus carneus MAK 259 has been investigated and demonstrate antibacterial, antibiofilm and synergistic activities against (MRSA) and (MDR P. aeruginosa). Results: In the current research, silver nanoparticles (AgNPs) and selenium nanoparticles (SeNPs) were produced extracellularly using A. carneus MAK 259 culture supernatants. Colour change, an initial evaluation of the production of AgNPs and SeNPs. Then, UV absorption peaks at 410 nm and 260 nm confirmed the production of AgNPs and SeNPs, respectively. AgNPs and SeNPs were dispersed consistently between 5‒26 nm and 20–77 nm in size, respectively using TEM. FT-IR analysis was used for assessing proteins bound to the produced nanoparticles. The crystallinity and stability of AgNPs and SeNPs was confirmed using X-ray diffraction analysis and zeta potential measurements, respectively. Antibacterial, antibiofilm and synergistic effects of both (NPs) with antibiotics against MRSA and MDR P. aeruginosa were tested by Agar well diffusion, tissue culture plate and disc diffusion method respectively. Both (NPs) inhibited the growth of P. aeruginosa more than S. aureus. But, SeNPs was stronger. AgNPs had stronger antibiofilm effect especially on biofilms producing S. aureus. as regard synergestic effects, Both (NPs) had higher synergestic effects in combination with cell wall inhibiting antibiotics against P. aeuroginosa While, on S. aureus with antibiotics that inhibit protein synthesis and affect metabolic pathways. Conclusions: Our study demonstrated that the mycosynthesized SeNPs had remarkable antibacterial effect while, mycosynthesized AgNPs exhibited a considerable antibiofilm effect. Both NPs exhibited higher synergistic effect with antibiotics with different modes of action. This approach could potentially enhance the efficacy of existing antibiotics, providing a new weapon against drug-resistant bacteria where the described silver and selenium nanoparticles play a pivotal role in revolutionizing healthcare practices, offering innovative solutions to combat antibiotic resistance, and contributing to the development of advanced medical technologies. [ABSTRACT FROM AUTHOR]

During petroleum production, flow assurance becomes a critical concern when asphaltene precipitation (AP) and deposition (AD) occur. Researchers have recently turned their attention to nanotechnology as a means to prevent and repair damage caused by AP and AD. This study introduces an effective inhibitor named GONEDA (graphene-oxide-N(1-naphthyl)-ethylenediamine) for asphaltene precipitation. The synthesis of functionalized nanoparticle was carried out using Hummer's technique. Subsequently, the synthesized nanoparticle was characterized through various experiments including x-ray diffraction, transmission electron microscopy, field emission-scanning electron microscopy, Fourier-transform infrared spectroscopy, dynamic light scattering, and Brunauer–Emmett–Teller analyses. These experiments have confirmed GONEDA's unique structural properties, such as large surface area, which enhance its ability to adsorb asphaltene molecules. Batch adsorption tests were conducted to measure the adsorption capacity and efficiency of nanoparticles toward asphaltene molecules. Additionally, the indirect method was employed to detect the onset point of AP and quantify the amount of precipitated asphaltene based on differences in the optical properties of the supernatant fluid. Findings indicate that increasing the concentration of GONEDA nanoparticles leads to a decrease in their capacity but an increase in efficiency. The abundance of oxygen atoms within the GONEDA structure allows preferential adsorption of asphaltene molecules, resulting in a favorable effect on delaying AP. Specifically, compared to reference synthetic oils, the newly developed nanoparticles delayed the onset of AP by approximately 26%, 20%, and 8% for the oils containing 1000, 3000, and 5000 ppm of asphaltene, respectively. Furthermore, the presence of GONEDA NPs decreased the amount of precipitated asphaltene. These results demonstrate significant potential for field-testing, despite the laboratory-scale nature of the experiments. [ABSTRACT FROM AUTHOR]

Malic acid-derived polyamides, polyhydrazides, and hydrazides exhibit strong potential for a variety of biological applications. This study demonstrates the synthesis of cobalt, silver, copper, zinc, and iron particles by a facile chemical reduction approach utilizing malic acid-derived polyamides, polyhydrazides, and hydrazides as stabilizing and reducing agents. Comprehensive characterization of the particles was performed using UV–Vis spectroscopy, FTIR, XRD, SEM, and EDX analysis. The synthesized particles included both zero-valent metals and oxides exhibiting mixed-phase compositions that may influence their functional properties. UV–vis analysis confirmed the formation of particles represented by the surface plasmon resonance (SPR) peaks specific to each metal particle. FTIR spectroscopy revealed the interaction of the metal particles with the polymer matrix owing to the significant contribution of functional groups in the processes of reduction and stabilization. Further structural insights were obtained via X-ray diffraction (XRD), which identified crystalline phases, and scanning electron microscopy (SEM), which demonstrated uniform morphologies. Additionally, energy-dispersive X-ray (EDX) analysis provided compositional details, affirming the purity and distribution of metallic elements. These findings highlight the potential of malic acid-derived polymers as versatile agents for nanoparticle synthesis with applications in catalysis, sensing, and biomedical technologies. [ABSTRACT FROM AUTHOR]

[Display omitted] • An overview of the global problem with electronic waste. • Importance of transforming wasted PCBs into value-added products. • Physical and hydro-processing methods to obtain an enrichment metal solution from PCBs. • The synthesis of nanoparticles using PCBs as a starting material. • Potential nanoparticles applications in cosmetics, cement, and cutting CO 2 emissions. Electronic waste (e-waste) is a global problem, and many countries have established laws and regulations to promote its proper disposal and recycling. E-waste contains a significant content of printed circuit boards (PCBs), composed of metals and other valuable metals that may become scarce in Earth's crust – Copper (Cu), nickel (Ni), gold (Au), silver (Ag), palladium (Pd), and others. The main objective of this review is to explore the potential for producing nanoparticles (NPs) from the metals extracted through PCB recycling, with applications in the cosmetics, cement manufacturing, and carbon dioxide (CO 2) capture industries. For this purpose, the recycling methods for PCBs e-waste, using physical processes (gravity, magnetic, electrostatic separation, and flotation), metallurgical processes (pyrometallurgy and hydrometallurgy), and purification techniques to obtain an enriched metal solution for the subsequent nanoparticle synthesis was performed. The production of NPs is a novel approach to obtain value-added products for industry. Therefore, recent research from pre-treatment of PCBs to NPs production is summarized, aligning with the circular economy principles and sustainable development goals. Towards this end, wasted PCBs can be transformed into valuable materials with innovative and potential applications in cosmetics, cement manufacturing, and carbon dioxide capture, contributing to a more sustainable future. [ABSTRACT FROM AUTHOR]

Objective(s): Scientists have focused on the development of new drug delivery systems including pHsensitive nanomaterials adaptive to tumor microenvironments. We aimed to fabricate a microfluidic system to synthesize and characterize curcumin (Cur)-containing PCL and Chitosan (CSN) polymeric nanoparticles against MCF7 breast cancer cells. Materials and Methods: The microfluidic chip was fabricated by photolithography and polydimethylsiloxane (PDMS) molding procedure. The chip was Y-shaped and equipped with two inlets and one outlet. PCL and Chitosan (CSN) were dissolved in acetic acid overnight and mixed with Cur for three hours. The prepared solution was injected from one inlet and a solution of tween 80 in distilled water was injected from the other inlet. The nanoparticles were characterized in size, electrical charge, structure, drug loading, and drug release efficiency. Finally, the cytotoxicity was assessed using the MTT assay at specific concentrations after 24 and 48 hr. Results: The mean diameter/zeta potentials of spherical-shaped nanoparticles with and without Cur were 209 ±2 nm / +15 and 219 ± 4 nm/+3, respectively. FTIR results confirmed the presence of all components in the nanoparticles. The Cur loading rate was 1.5%, and Cur represented a sustained release manner. Also, the release profile showed faster release in a low-pH medium. MTT assay results showed that Cur-containing nanoparticles exerted a significant effect on cell viability. Conclusion: It can be concluded that microfluidic systems can pave the way for nanoparticle synthesis easily rapidly and cost-effectively for cancer agent delivery. Based on our observations, PCL-CSN-loaded Cur nanoparticles represent appropriate characteristics and suitable anti-cancer effects. [ABSTRACT FROM AUTHOR]

This study demonstrates the feasibility of extracting lecithin from oil industry byproducts in an eco‐friendly manner, with minimal use of water and without harmful chemicals. Liposomes can be generated directly from this extracted lecithin, enhancing the value of these byproducts and enabling the production of catalytic gold nanoparticles (AuNPs). Thin‐layer chromatography of the extracted lecithin revealed a phospholipid composition primarily consisting of phosphatidylethanolamine and phosphatidylcholine, and surface tension studies demonstrated similar behavior between the extracted and commercial lecithin. Liposome formation using sustainable lecithin (LPn) resulted in structures that were stable for at least 10 days, exhibiting a low polydispersity index (0.395) and uniform size (approximately 214 ± 7 nm). Gold nanoparticles were synthesized successfully in LPn loaded with [HAuCl4] by using different photoreduction methods: ultraviolet (UV) lamp, pulsed laser 355 nm, and sunlight irradiation. The AuNPs exhibited characteristic sizes (ranging from 5.03 to 6.78 nm) and optical properties typical of nanoparticles, including a distinct surface plasmon resonance. As a proof of concept, we also demonstrated that the synthesized AuNPs exhibited catalytic activity in UV‐induced cis‐trans isomerization reactions. Overall, the study highlights the potential of sustainable soy lecithin extraction for diverse applications, including nanoparticle synthesis and catalysis. [ABSTRACT FROM AUTHOR]

This study presents the successful synthesis of Sr2Ta2O7 with a pyrochlore crystal structure, which was previously unreported. Traditionally, Sr2Ta2O7 is synthesized in an orthorhombic layered perovskite‐type structure using traditional solid‐state reaction and batch‐type subcritical hydrothermal methods. Here, we utilize a continuous‐flow supercritical hydrothermal method, a technique primarily applied for nanoparticle synthesis and minimally explored for the synthesis of metastable crystals. Through detailed evaluations employing X‐ray diffraction and scanning electron microscopy, we confirmed the synthesis of the pyrochlore phase, characterized by particles with a diameter of less than 100 nm, synthesized at 633 K. Notably, the synthesized pyrochlore structure demonstrated remarkable stability, even after thermal treatment at 773 K for 1 h. Pyrochlore Sr2Ta2O7 stands out as a rare exception to the traditional tolerance factor approach among 278 known A2B2O7 compositions. Systematic evaluation of formation energies through first‐principles calculations revealed that the pyrochlore Sr2Ta2O7 synthesized in this study is located 0.06 eV/atom above the convex hull. This achievement underscores the potential of the continuous‐flow supercritical hydrothermal method in automating the exploration and discovery of novel crystal structures, suggesting a systematic pathway for advancing the field of material synthesis. [ABSTRACT FROM AUTHOR]

The ZnO-NPs have been successfully produced and characterized using Coffea arabica extract using the green method. The successful formation of nanoparticles was indicated by a color change brown. Phytochemical characterization revealed that Coffea arabica extract is rich in bioactive compounds, including alkaloids, flavonoids, and phenolics, which have significant antioxidant potential. The results of the antioxidant activity tests showed that increasing concentrations of Coffea arabica extract correlated with enhanced free radical scavenging activity, with a relatively low IC50 value, indicating this coffee extract can serve as an effective source of antioxidants. Histological assessment revealed damage to cell structures due to exposure to ZnO-NPs, including membrane dilation, epithelial layer damage, and signs of apoptosis and necrosis. The ZnO-NPs synthesized result from Coffea arabica extract showed possess larvicidal potential and beneficial antioxidant properties, however attention is needed regarding potential toxicity at certain concentrations. [ABSTRACT FROM AUTHOR]

In this work, a comparison of the photocatalytic activity of free-standing Cu-based nanoparticle mixtures and spin-coated nanoparticle films under visible-light radiation is conducted. Herein, Cu2O, Cu2O-Cu, Cu2O-Cu3N-Cu, and Cu3N-Cu nanoparticle mixtures were successfully synthesized by a non-aqueous sol–gel route and then deposited on a glass substrate by spin-coating. The surface chemistry of the nanoparticles studied by X-ray photoelectron spectroscopy (XPS) allowed elucidating the nanoparticle synthesis mechanism. The UV–Vis absorption spectroscopy illustrates that photocatalytic activity is attributed to the high specific surface of the nanoparticles and their wider absorption range region from 500 to 1100 nm. Unlike the free-standing photocatalysts, the photocatalytic effect of spin-coated nanoparticle films enabled their facile reclamation, which solves a key issue for practical applications of the photocatalysts. The photocatalytic performances on neutral red and malachite green organic dyes were influenced by the type of visible light sources, i.e., solar simulator and natural sunlight. The results indicate that photodegradation efficiency is the highest for Cu2O nanoparticles, reaching values of 82% for neutral red and 94% for malachite green. We also demonstrate that the degradation of cationic neutral red undergoes a photoconversion to its neutral form during the degradation process, which in turn, lowers its degradation efficiency. On the other hand, higher degradation efficiency was observed on malachite green owing to its unique cationic form, soluble in aqueous solutions. [ABSTRACT FROM AUTHOR]

Nanomaterials are materials at the nanometric scale that have distinctive functionalities and properties. Due to their unique properties relative to traditional materials, nanomaterials attract great interest from researchers. ZnO-based nanomaterials especially demonstrate versatility, accessibility, biocompatibility and low toxicity. In recent years, there has been a growing interest in developing eco-friendly and sustainable approaches for synthesizing nanomaterials. In the development of ecological techniques for their synthesis, using natural resources is a popular choice. Employing egg white for ZnO nanoparticle synthesis represents an environmentally method that uses a natural resource. The great advantage of green synthesis using egg white is that it is a cost-effective, renewable, and bio-degradable resource that offers biocompatibility. Egg white is rich in proteins, amino acids, and other biomolecules that possess reducing properties. These biomolecules interact with metal ions, leading to the reduction and nucleation of nanoparticles. Additionally, the proteins in egg white act as capping agents, stabilizing the nanoparticles and preventing their aggregation. The proteins of white albumen have different functional groups and maintain product attributes, such as dispersion and stability. This paper focuses on the characterization of ZnO nanoparticles obtained by the assisted synthesis of egg white. This study explores the potential of ovalbumin, the major protein in egg white, as a template for the synthesis of nanostructured ZnO. The synthesis process utilized egg white from different sources (commercially raised hens, home-raised hens, and ducks) and varying zinc nitrate concentrations (1M and 2M) to evaluate their influence on nanoparticle morphology and size. Various complementary techniques are employed to analyze the resulting nanostructures: XRD, SEM, and ATR-FTIR. Also, antibacterial properties are investigated. This study underscores the viability of different egg whites as a green resources for synthesizing nanostructured ZnO and contributes to the development of sustainable nanotechnology approaches. [ABSTRACT FROM AUTHOR]

The present research aims to valorize biofloc waste by extracting polyphenols via alkaline hydrolysis, utilizing them as reducing and stabilizing agents in the optimization of green synthesis of silver nanoparticles (BIOAgNPs). For the alkaline extractions, potassium hydroxide (KOH) concentrations of 0 to 4 M were used in combination with ultrasound. Total polyphenol content and antioxidant activity were evaluated. BIOAgNPs synthesis was optimized using the response surface methodology and central composite design. The parameters time, temperature, AgNO3 concentration, and the percentage of the biofloc extract (2 M KOH), with measurements taken for the area under the curve (AUC) (400–500 nm) and the mean hydrodynamic diameter (DLS), were evaluated. Antibacterial activity was determined for Gram-negative and Gram-positive bacteria. Higher polyphenol content and antioxidant activity were observed using 2 M KOH. The optimized model for DLS and the AUC was obtained in 4 h, at 40 °C, using 2.4 mM AgNO3 and obtaining 2.5% of extract. Optimized BIOAgNPs had a diameter of 22.4 nm, hydrodynamic diameter of 106.5 nm, zeta potential of −28 mV, and polydispersity index of 0.26. BIOAgNPs demonstrated bactericidal activities. This study enhanced the valorization of aquaculture residues through improved polyphenol extraction techniques and developed an effective methodology for synthesizing silver nanoparticles with antimicrobial activity. [ABSTRACT FROM AUTHOR]

Waste recycling as secondary source has become important from the environmental perspective and the circular economy. In this context, any waste can become raw material to manufacture other products, such as nanoparticles. Thus, this study aims to provide a descriptive and critical view of metal recovery techniques and later use them as raw materials for nanoparticle synthesis. After scoping searches, an investigation was carried out and found a gap in the research on synthesizing nanoparticles from secondary sources. The possible technologies to recover metals are hydrometallurgical processes, pyrolysis, and bioleaching followed by purification processes. The advantages and disadvantages were discussed. Based on this analysis, hydrometallurgical processing was identified as the most suitable method and, consequently, the most used method for synthesizing nanoparticles. There is a difference in the size and shapes of nanoparticles synthesized by secondary sources and commercial salts. [ABSTRACT FROM AUTHOR]

This work reports the fabrication of p‐type Si micropillar (MP) substrates decorated with AgxCu100−x bimetallic nanoparticles and their application as photocathodes for CO2 photoelectrochemical reduction. Metal deposition by metal‐assisted chemical etching is chosen as the nanoparticle synthesis method, to explore for the first time its capabilities for 3D structures. It is found to be applicable, allowing a good control of the composition, with nanoparticles distributed along the entire MP, but with a coverage gradient from top to bottom. The AgxCu100−x decorated Si MPs photocathodes show enhanced light trapping compared to flat Si, with 45 % lower reflectance values in the visible and significantly higher catalytic activity, in terms of photocurrent density, overpotential and power savings (4.7 % for Ag50Cu50/Si MPs vs. 3 % for Ag50Cu50/flat‐Si). Si MPs coated with Ag50Cu50 and Ag20Cu80 provide the highest gain in potential (440 and 600 mV vs. bare Si MPs) and an increased selectivity towards high energy density products (i. e., CH4) compared to monometallic photocathodes. These are promising features for efficient light‐driven CO2 conversion. However, a significant metal loss is observed during photoelectrolysis, especially for Cu‐rich compositions. Suggestions to improve the photocathode performance in terms of metal coating homogeneity and catalyst stability are presented. [ABSTRACT FROM AUTHOR]

AbstractZinc Oxide Nanoparticles (ZnO NPs) are highly efficient photocatalysts, applied in areas such as self-cleaning, antimicrobial protection, UV-blocking, and anti-fogging. Their photocatalytic performance depends on factors like size, shape, and surface area, which can be controlled through morphology. In this study, Cetyltrimethyl Ammonium Bromide (CTAB) was used as a template to design ZnO nanorods, with Spirulina plantesis acting as a capping agent to ensure uniform size distribution. CTAB, a cationic surfactant, reduces surface tension, enabling more even dispersion of ZnO particles in a sol-gel medium, as observed through SEM imaging. The study focused on modifying ZnO morphology by adjusting the CTAB molar ratio (10%, 20%, and 30%) to the Zn(NO3)2 precursor. Characterization techniques such as TGA-DTA, FT-IR, XRD, BET/BJH, UV-VIS-DRS, and SEM were employed. Results showed that CTAB significantly reduced ZnO crystal size, improving particle homogeneity, with average sizes of 30.7, 29.8, and 27.6 nm, compared to 32.5 nm without CTAB. XRD analysis confirmed the ZnO phase with a P63mc space group (a = b = 3.25254 Å, c = 5.2110 Å, α = β = 90°, γ = 120°). The most enhanced photocatalytic activity was observed in the ZnO-CTAB-20 formulation, particularly in antibacterial tests against Staphylococcus epidermidis and Pseudomonas aeruginosa. [ABSTRACT FROM AUTHOR]

Ascorbic acid (AA) is the most widely used reductant for noble metal nanoparticle (NP) synthesis. Despite the synthetic relevance, its aqueous chemistry remains misunderstood, due in part to various assumptions about its reduction pathway which are insufficiently supported by experimental evidence. This study aims to provide an understanding of the complex chemistry associated with AA under aqueous conditions. We demonstrate that (i) AA undergoes appreciable degradation in alkaline solution on a timescale relevant to NP synthesis, (ii) contrary to popular belief, AA does not degrade into dehydroascorbic acid (DHA), nor is DHA the oxidized product of AA under noble metal NP synthetic conditions, (iii) DHA, which readily degrades under alkaline conditions, can also effectively reduce metal salt precursors to metal NPs, (iv) neither ascorbate nor dehydroascorbate act as surface capping agents post‐synthetically on the NPs (v) AA degradation time greatly affects the morphology and polydispersity of the resultant NP. Results from our mechanistic investigation enabled us to utilize purposefully‐aged reductants to achieve control over shape yield and monodispersity in the seed‐mediated synthesis of Au nanorods. Our findings have important implications for achieving monodispersed products in the many metal NP synthesis reactions that make use of AA as a reducing agent. [ABSTRACT FROM AUTHOR]

Flexible electrets can be used to construct eco‐friendly devices that utilize dielectric materials to measure physical parameters without requiring any power supply. By achieving detection capabilities that surpass human tactile abilities, such devices can be employed to create super‐sensing technologies, such as electronic artificial skin, based on solution processes. In this study, electret‐type particles with self‐power‐generating properties are synthesized and applied to flexible pressure sensors. Notably, an ultrafast response is achieved despite the device being flexible and fabricated using a solution process. Moreover, this technology is successfully implemented in both human and robot applications, detecting tactile signals in real‐time and serving as electronic artificial skin—a key super‐sensing aspect. These results showcase the possibilities offered by high‐performance flexible sensing technology and illuminate potential directions for future applications. [ABSTRACT FROM AUTHOR]

Background: Impression materials can harbour microorganisms from saliva and blood, posing cross-contamination risks. However, post-setting disinfection might compromise the dimensional accuracy and mechanical properties of alginates. Hence, it was the aim of this research to assess the detail reproduction, tear strength, elastic recovery, and surface quality of the gypsum model of newly developed dental alginates with inherent antimicrobial properties. Methods: Three dental alginate groups with antimicrobial alterations were formulated. One group replaced water with 0.2% chlorhexidine solution (CHX group), while the other two utilized water-based extracts of Syzygium aromaticum (SA, clove) or Zingiber officinale (ZO, ginger) to reduce silver nitrate, resulting in two silver nanoparticles (AgNPs)/extract (clove or ginger) mixture solutions. These mixture solutions were employed for the preparation of dental alginate yielding the SA + AgNP and ZO + AgNPs groups. All modified groups were compared to an unmodified control group that used water for mixing. Elastic recovery, detail reproduction, and tear strength were assessed following the ISO 21563:2021 standard. The surface roughness of plaster models was analysed using the optical profilometer. Elastic recovery was assessed by applying and then releasing load on alginate specimens to measure their ability to recover from deformation. Detail reproduction was evaluated by observing the reproducibility of a 50 μm line in a metallic mold using a light microscope, while tear strength was determined by stretching the specimens until failure at a constant speed of 500 mm/min. Results: All tested groups exhibited elastic recovery values meeting ISO standards for hydrocolloid impression materials. Regarding detail reproduction, both the control and modified alginates successfully reproduced the 50-µm line without interruption in all specimens. Tear strength values for all tested groups remained within the acceptable documented ranges, surpassing the minimum requirement of 0.38 N/mm as mandated by ISO 21563:2021. The ZO + AgNPs (0.94 ± 0.17 N/mm) demonstrated significantly higher tear strength values and surface roughness values compared to the other tested groups. Conclusions: Chlorhexidine, Syzygium aromaticum, and Zingiber officinale green-synthesized silver nanoparticles are promising, cost-effective alternatives for disinfecting alginate impressions without compromising performance. Green nanoparticle synthesis is a safe, efficient, and non-toxic method, potentially synergizing metal ions with plant extract. [ABSTRACT FROM AUTHOR]

Featured Application: Further research and improved data collection methods are essential, to reduce uncertainty and ensure comprehensive environmental evaluations. This review provides a comprehensive Life Cycle Assessment (LCA) of a cosmetic cream to assess the environmental impacts throughout its entire life cycle, from raw material extraction to disposal, using the methodology according to international standards. The LCA was performed using the OpenLCA 2.0.1 software, with data from the Ecoinvent 3.8 database and relevant literature. The assessment focused on multiple impact categories, including climate change, acidification, eutrophication (freshwater, marine and terrestrial), ecotoxicity (freshwater), human toxicity (cancer and non-cancer), ionizing radiation, land use, ozone depletion, photochemical ozone formation, resource use (fossils, minerals and metals), and water use. The LCA of a cosmetic cream containing gold nanoparticles revealed significant environmental impacts across critical categories. The total climate change potential was 2596.95 kg CO2 eq., driven primarily by nanoparticle synthesis (60.7%) and electricity use (31.9%). Eutrophication of freshwater had the highest normalized result (3.000), with nanoparticle synthesis contributing heavily, indicating the need for improved wastewater treatment. The resource use (minerals and metals) scored 1.856, while the freshwater ecotoxicity reached 80,317.23 CTUe, both driven by the nanoparticle production. The human toxicity potentials were 1.39 × 10−6 CTUh (cancer) and 7.45 × 10−5 CTUh (non-cancer), linked to emissions from synthesis and energy use. The LCA of the cosmetic cream revealed several critical areas of environmental impact. The most significant impacts are associated with gold nanoparticle synthesis and electricity use. Addressing these impacts through optimized synthesis processes, improved energy efficiency, and alternative materials can enhance the product's sustainability profile significantly. [ABSTRACT FROM AUTHOR]

Micro pollutants pose a significant issue in water ecosystems. Particularly high concentrations of 17β‐estradiol (E2) have been identified in agricultural wastewater, which poses harmful effects on aquatic organisms and disrupts ecosystem balance. Therefore, effective determination of E2 from water sources is crucial. This study developed a biosensor capable of detecting E2 in wastewater using specific polymer nanoparticle synthesis through molecular imprinting. Est‐imp‐poly(multi‐walled carbon nanotubes‐glycidyl methacrylate [MWCNT‐GMA]) polymer nanoparticles were synthesized using a surfactant‐free emulsion polymerization method, and their characterization was conducted using FTIR and scanning electron microscopy (SEM) technologies. The Qmax value for Est‐imp‐poly(MWCNT‐GMA) nanoparticles in a 1 mg/mL E2 solution was determined to be 140 ppm. Comparing adsorption capacities, the molecularly imprinted nanoparticles (MIP) showed nearly five times higher E2 adsorption compared to non‐imprinted polymers (NIP). The Est‐imp‐poly(MWCNT‐GMA)‐Nafion/screen‐printed electrode (SPE) system was employed for analyzing wastewater samples. The current measurements taken at various concentrations in the wastewater consistently matched the E2 concentration calibration curve. The limit of detection (LoD) and limit of quantification (LoQ) were determined to be 0.042 and 0.12 μM, respectively. The biosensor demonstrated a linear working range from 0.12 to 50 μM, with a high correlation coefficient (R2 = 0.9927). These results highlight the potential of the developed biosensor for detecting E2 in real samples. [ABSTRACT FROM AUTHOR]

We report the synthesis of silver nanoparticles (Ag NPs) functionalized with L‐cysteine (Ag‐cys NPs) for colorimetric detection of contaminants: Hg2+, Pb2+, Cr6+ (CrO42−/Cr2O72), and As3+ in water samples. AgNPs synthesized were obtained in water from the mixture of the cationic and non‐ionic surfactants, cetyltrimethylammonium bromide (CTAB) and nonylphenol ethoxylate (NP‐10), respectively. Physicochemical characterization demonstrated a monomodal distribution of spherical nanoparticles with an average size of 8.25 nm. The stability of the Ag‐cys NPs was evaluated by determining the surface charge, which was found to be +27.95 mV, indicating the stability of Ag‐cys NPs against flocculation. The interaction between Ag‐cys NPs and solutions of contaminants was studied. This was done by measuring the shift in LSPR band of Ag NPs covered with cys in the region of 400–450 nm. We observed a change or disappearance of color visually, indicating aggregation or oxidation of the Ag NPs. Concentration of cys, as well as the pH of the nanoparticles, were crucial in studying the aggregation process. This is a preliminary study in search of benefits such as low cost, in situ usability, ease of use, and rapid response making it a potential alternative to traditionally employed spectroscopic methods. [ABSTRACT FROM AUTHOR]

This study focuses on the synthesis of zinc oxide (ZnO) nanoparticles using lemon peel as a green and sustainable precursor. ZnO is a metal oxide semiconductor known for its broad direct bandgap and photocatalytic properties. Lemon peel, a waste product rich in natural compounds, is utilized as a reducing and stabilizing agent during the synthesis process. The sol-gel method is employed to extract the active ingredients from lemon peel and combine them with a zinc salt solution. The resulting mixture undergoes controlled thermal treatment to produce ZnO nanoparticles. The synthesized nanoparticles are characterized using techniques such as field emission scanning electron microscopy (FESEM), X-ray diffraction (XRD), and UV-Vis spectroscopy to analyze their morphology, structure, and optical properties. The results demonstrate the viability of using lemon peel as a sustainable and low-cost precursor to produce ZnO nanoparticles. The environmentally friendly synthesis method offers potential applications in catalysis, optoelectronics, energy conversion, and biomedicine. The findings highlight the benefits of utilizing natural waste products in nanoparticle synthesis, promoting a more eco-friendly and efficient approach to material production. [ABSTRACT FROM AUTHOR]

Controlling the size and composition of metal nanoparticles is of considerable interest, as these are essential to their catalytic properties. Recently, our group has developed a preorganization strategy for controlled Ir nanoparticle synthesis inside Pt12L24 nanospheres. In the current contribution, we expand this method to the controlled synthesis of Rh nanoparticles. The encapsulated RhI complexes (Rh‐s @ G‐sphere) led to reasonable size control (2.8 ± 0.9 nm). Next, we demonstrated the formation of Rh‐Ir alloyed nanoparticles with varying Rh/Ir compositions, by preorganization of the respective metal complexes inside Pt12L24 nanospheres based on complementary hydrogen bonds before the reduction step that leads to nanoparticle formation. These heterometallic particles were evaluated in the hydrogenation of cinnamaldehyde (7) as a probe reaction. Besides a high activity in this probe reaction, the Rh particles also catalyzed the conversion of the solvent (CH3CN). The formed basic amine leads to follow‐up reactions of the product and compatibility issues with the hosting nanosphere. The solvent hydrogenation was effectively suppressed by using the Rh:Ir alloyed nanoparticles, provided that they contain > 66% Ir. Compared to the monometallic Ir particles (Ir‐s @ G‐sphere), the Rh:Ir alloyed nanoparticles displayed higher catalytic activity, reaching optimal selectivity and activity at an 8:16–Rh:Ir ratio. The combined catalytic results illustrate that preorganization of the metal complexes in the nanosphere before the reduction with hydrogen effectively facilitates the formation of Rh:Ir alloyed nanoparticles, which allows for tuning a catalyst to create a more active and selective catalyst compared to monometallic or nonencapsulated Rh/Ir particles. [ABSTRACT FROM AUTHOR]

Plant-mediated synthesis of nanoparticles (NPs) has emerged as an eco-friendly and cost-effective method, utilizing the reducing and capping properties of plant extracts for NPs fabrication. This review explores the influence of various plant parts such as leaves, seeds, roots, fruits, and flowers, on the morphology, size, and antibacterial activity of metal and metal-oxide NPs. Through comprehensive analysis of numerous studies, we elucidate how plant-derived carbohydrates and other phytochemicals impact the synthesis and characteristics of NPs. Nanoparticles synthesized with different parts of plants have successfully proved as antibacterial agents displaying significant zone of inhibition (ZOI). For instance, green tea leaf extract yields spherical silver NPs (15–33 nm) with potent antibacterial properties of ZOI of 11 mm and 10 mm toward S. aureus and K. pneumoniae, while Trigonella foenum-graecum seed extracts result in irregularly spherical zinc oxide (ZnO) NPs (70–90 nm) effective against bacterial strains. Moringa oleifera root extracts lead to the formation of hexagonal-shaped ZnO NPs (15–40 nm) with significant antibacterial activity with ZOI of 11.6 mm and 12.5 mm against B. subtilis and E. coli, and Myristica fragrans fruit extracts produce elliptical and spherical NPs (41.23 nm) effective against various bacterial strains such as E. coli (ZOI = 15 mm), S. aureus (ZOI = 21 mm), and K. pneumoniae (ZOI = 27 mm). Cassia auriculata flower extracts generate flake-structured NPs (41 nm) with potent antibacterial action against E. coli, S. aureus, K. pneumoniae, S. pneumoniae. This review highlights the innovative potential of plant-mediated nanoparticle synthesis and emphasizes the importance of selecting specific plant's part by understanding the unique contributions of its phytochemicals to tailor NPs properties for diverse applications, particularly in the development of effective antibacterial formulations. [ABSTRACT FROM AUTHOR]

Addressing the pressing challenge of developing sustainable and cost-effective nanoparticle synthesis methods, this study introduces an innovative approach to green nanotechnology. We present a novel method for fabricating copper oxide nanoparticles (CuO NPs) by harnessing the unique properties of Trigonella foenum-graecum (TFG) extract. Through thorough X-ray diffraction analysis, this work confirms the successful synthesis of CuO, distinguished by its monoclinic phase and remarkably small crystallite size of 6.23 nm, indicative of enhanced reactivity and surface area. Further elucidation via Fourier-transform infrared (FTIR) spectroscopy reveals the intricate functionalization of CuO with TFG phytochemicals, providing insights into the surface chemistry and potential interactions with environmental contaminants. Mainly, the crystalline structure of the synthesized CuO is unequivocally affirmed through selected area electron diffraction signals, corroborating the purity and crystallinity of the nanoparticles. Emphasizing the distinctiveness of our synthesis method, the emergence of well-defined absorption peaks at 271 nm and 375 nm and energy band gaps of 3.58 eV and 4.00 eV underscores the efficient fabrication of CuO nanoparticles with tailored optical properties, crucial for various applications, including photocatalysis. FESEM visualization revealed spherical forms and interconnected cylindrical structures, while HRTEM analysis confirmed the heterogeneous nature of the nanoparticles. Equally impressive is the demonstrated capability of the synthesized nanoparticles in degrading methyl green (MG) dye, a notorious environmental pollutant known for its persistence and adverse effects. Leveraging a concentration of 200 mg L− 1, our findings demonstrate a remarkable 97% removal of dye (initial concentration 100 mg L− 1) achieved within a concise 100-minute timeframe, driven by pseudo-first-order kinetics. [ABSTRACT FROM AUTHOR]

The antibacterial and anticancer potential of silver nanoparticles (Ag-NPs) is promising for cancer treatment and fighting multidrug-resistant bacteria. This study introduces the first eco-friendly synthesis of Ag-NPs using a cell-free extract (CFE) of Chaetomium olivaceum strain B422 isolated from grapevine. In this study, ten fungal strains collected from grapevine trunks and twigs were purified and cultured on potato dextrose agar (PDA) at 25 °C (pH 5) under dark conditions for 7 to 14 days. Ag-NPs were synthesized using CFEs of the fungal strains and silver nitrate as precursor. The biosynthesis process was optimized by varying factors such as silver nitrate concentration, pH, temperature, agitation speed and incubation time using a one-factor-at-a-time approach. The synthesized Ag-NPs were characterized for various properties such as size, structure and stability using UV-Vis spectroscopy, field emission scanning electron microscopy (FESEM), dynamic light scattering (DLS), Raman spectroscopy and X-ray diffraction (XRD). Of the ten fungal strains studied, only strain B422, identified as C. olivaceum by phylogenetic analysis of DNA sequence data, successfully synthesized Ag-NPs by reduction of silver nitrate. This was confirmed by a color change to dark brown and a distinct UV-Vis absorption peak at 425 nm. Optimal conditions for biosynthesis were found to be 5 mM silver nitrate, pH 7, 35°C, no shaking and an incubation period of 96-120 h. FE-SEM analysis revealed nanoparticles ranging in size from 2 to 92 nm, with an average size of 32 to 42 nm, while DLS analysis revealed a hydrodynamic size of 46.3 nm. Zeta potential measurements showed high stability (-23.5 mV). Raman spectroscopy identified functional groups associated with the Ag-NPs and XRD confirmed their crystalline structure. The sustainable synthesis of Ag-NPs using fungal CFE allows precise control of nanoparticle size and morphology, making it highly relevant for biomedical applications and a significant advancement in green nanotechnology for healthcare. [ABSTRACT FROM AUTHOR]

The choice of plant species is crucial, as different plants provide unique biomolecules that influence nanoparticle characteristics. Biomolecules in plant extracts, such as proteins, amino acids, enzymes, polysaccharides, alkaloids, tannins, phenolics, saponins, terpenoids, and vitamins, act as stabilizing and reducing agents. This study explores the synthesis of silver nanoparticles (AgNPs) using leaf extracts from collard greens (Brassica oleracea var. acephala), hazelnut (Corylus avellana var. avellana), and green tea (Camellia sinensis). NPs were synthesized using silver nitrate (AgNO3) solution at two different molarities (1 mM and 5 mM) and characterized by UV–Vis spectroscopy, XRD, TEM, and FTIR. The Surface Plasmon Resonance (SPR) peaks appeared rapidly for hazelnut and green tea extracts, within 30 and 15 min, respectively, while collard greens extract failed to produce a distinct SPR peak. X-Ray Diffraction confirmed the formation of face-centered cubic silver. TEM analysis revealed high polydispersity and agglomeration in all samples, with particle size generally decreasing at higher AgNO3 concentrations. However, hazelnut extract showed a slight increase in size at higher molarity. Among all samples, green tea-derived AgNPs synthesized with 5 mM AgNO3 were the smallest and least polydisperse, highlighting the significant role of plant type in optimizing nanoparticle synthesis. [ABSTRACT FROM AUTHOR]

This work is a comparative study of the effect of two different annealing methods on copper oxide (CuO) nanoparticle properties obtained previously by direct precipitation method. The prepared samples were annealed in air at various temperatures (300, 400, 500°C) for 1 hour. Then they were characterized by employing scanning electron microscopy (SEM), X-ray diffraction (XRD), UV-Visible, and Fourier Transform Infrared (FT-IR) spectroscopy. The main results revealed an increase in the grain size in both methods as the annealing temperature increases. It reaches 30.93 nm in RTA and 26.75 nm in STA at 500°C. XRD spectra showed, in the case of RTA at 500 °C, a significant decrease in the intensity corresponding to the (002) and (111) orientations. This result indicated that beyond 400 °C, one hour of RTA is not suitable for enhancing CuO nanoparticle crystallinity compared to STA. The optical analysis demonstrated that the energy of the optical band gap in STA is higher than that in RTA. It reaches 2,88 eV at 500°C using RTA which is close to the gap value of CuO in the range of 1.8--2.8 eV. FT-IR results showed, for both methods, the presence of characteristic peaks of the Cu-O bonds in the monoclinic CuO structure without any trace of Cu2O structure. Nevertheless, samples exposed to RTA for one hour are more susceptible to absorbing species of C=O bond (C=O bond is due to the atmospheric CO2 absorption and the presence of organic impurities from the synthesis process) than those of STA. Hence, RTA at 500 °C is far from producing CuO nanoparticles with preferred characteristics; it needs further research to examine the effect of higher temperature by controlling the annealing time. [ABSTRACT FROM AUTHOR]

This study presents the synthesis of metal nanoparticles (NPs) with antimicrobial properties from cyanobacterial biomass. Silver (AgNP), copper (CuNP), and zinc (ZnNP) nanoparticles were prepared from exopolysaccharides (EPSs) obtained from isolated cyanobacterial strains. The antimicrobial activity of AgNPs against Escherichia coli and Staphylococcus aureus was evaluated, and compared with CuNPs and ZnNPs, AgNPs were found to have a greater capacity to inhibit bacterial growth. The main factors influencing antimicrobial activity are the concentration and type of metal used. Using an optimized experimental design, specific conditions were established to maximize the antimicrobial efficacy of the synthesized NPs. The characterization of the nanoparticles included UV–VIS, FTIR, and EDX techniques, which confirmed the formation and purity of the AgNPs. This study highlights the effectiveness of cyanobacterial EPS as a reducing and stabilizing agent and provides a sustainable and efficient alternative for producing nanoparticles with biomedical applications. [ABSTRACT FROM AUTHOR]

Pancreatic cancer affects many people and is quite aggressive. Metallic nanoparticles may be an alternative treatment for this disease. In this work, the antiproliferative activity of biosynthesized silver nanoparticles was evaluated. Stenocereus queretaroensis peel extract was used as a reducing agent for nanoparticle synthesis; the characterization was carried out using spectroscopic techniques, X-ray diffraction, and microscopy. The antiproliferative effect was evaluated in the MIA PaCa-2 pancreatic tumoral cell line, and a molecular docking test was run with the STAT3 protein. The results obtained show that it was possible to synthesize silver nanoparticles from the plant extract, which was confirmed through characterization studies. The average size of the nanoparticles was measured to be 48.8 nm, and they predominantly exhibited a spherical shape. The antiproliferative effect was demonstrated in the pancreatic cell line, with an IC50 value of 15.66 µg/mL. The molecular docking analysis predicted a strong interaction with the STAT3 protein, with a binding energy value of −6.47 obtained. With these results, it is concluded that biosynthesized silver nanoparticles inhibit pancreatic tumor cell growth and may represent an innovative cancer treatment. [ABSTRACT FROM AUTHOR]

This study explores enhancing epoxy polymers with cerium aluminate (CeAlO3) nanoparticles via a solution combustion process. CeAlO3 loading (0.5 to 2.5 wt.%) significantly influences resulting composite properties. Characterization techniques confirm CeAlO3 presence, porous spherical morphology, and formation. FTIR spectroscopy identifies functional groups, while TGA shows excellent thermal stability below 200 °C, with minimal mass loss, and stability at 900 °C. The composites exhibit enhanced properties, with maximum tensile strength at 0.5 wt.%, a linear increase in tensile modulus up to 2.5 wt.%, and maximum compressive strength at 0.5 wt.%, with increasing modulus at higher filler loadings. These findings suggest CeAlO3-filled epoxy composites hold promise for high-temperature applications, emphasizing the importance of low filler concentrations for optimal structural properties. Overall, this research underscores the potential of CeAlO3 nanoparticles in advancing epoxy-based materials across various industries. [ABSTRACT FROM AUTHOR]

Bacterial cellulose (BC) has earned a well-defined place among biopolymers due to its unique physicochemical properties. Unfortunately, native BC lacks antimicrobial and antioxidant properties. To address this limitation, many BC-based nanocomposites with antimicrobial properties have been developed, primarily for applications in the biomedical field, but also for use in food packaging. Many nanoparticles can be incorporated into BC membranes, often in combination with other bioactive molecules. Among the available methods for nanoparticle synthesis, green synthesis has emerged as promising, as it avoids the use of hazardous chemicals. The aim of this paper is to develop and characterize antimicrobial composite materials fabricated using carboxymethyl cellulose (CMC) and bacterial cellulose fibrils loaded with zinc oxide and silver nanoparticles (NPs) obtained using turmeric extract by green synthesis. NP-loaded CMC-BC composites were characterized using scanning electron microscopy (SEM) coupled with energy dispersive X-ray spectroscopy (EDX), attenuated total reflectance-Fourier transform infrared (ATR-FTIR) spectroscopy, Grazing incidence X-ray diffraction (GI-XRD), and thermal analysis (TA). The antibacterial potential of such composites was tested against Escherichia coli (E. coli), Bacillus subtilis (B. subtilis), and Candida albicans (C. albicans). [ABSTRACT FROM AUTHOR]