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Nonessential heavy metals are toxic to human health. In this study, mercury, a hazardous metal, was detected by colorimetric analysis using Murraya koenigii. The eco-friendliness of this method was also emphasized. UV spectrum is a broad peak observed at 200-250 nm in P. guajava leaf extracts. The UV spectrum of green synthesized P. guajava exhibited an absorption band of 418 nm, which confirms the nanoparticle synthesis. FTIR analysis of the vibrational peak around 3307 cm-1 is assigned to ?(O-H) stretching that could possibly emanate from carbohydrates or phenolics. The peaks found around 2917 and 2849 cm-1 are ascribed to the -C-H stretch of the alkyl group, and the peak around 1625 cm-1 is due to the enolic ß-diketones or -C = O stretch of carboxylic acids, while the corresponding -C-O stretch is observed around 1375 and 1029 cm-1. The assignment of peaks is similar. It is clear from the SEM image that the constituent parts were non-uniform sphere-shaped, agglomerated, and of an average size of 30.9 nm. XRD analysis was utilized to determine the structural characteristics and crystalline nature of P. guajava. The observed intensity peaks at 32.35°, 36.69°, 39.24°, 44.76°, 59.42°, and 67.35° represent the 2? values for P. guajava in the diffraction pattern, aligning with the values in the standard database. The synthesized AgNPs tested antibacterial properties against various strains of microorganisms, including Escherichia coli, 25 µg/mL 6.02 ± 0.17 and 100 µg/mL 7.3 ± 0.05, Staphylococcus aureus, 25 µg/mL 05.02 ± 0.07 and 100 µg/mL 11.3 ± 1.12, Streptococcus mutans, 25 µg/mL 04.02 ± 0.19 and 100 µg/mL 11.1 ± 0.11, Enterococcus faecalis, 25 µg/mL 0.8.05 ± 0.11 and 100 µg/mL 11.7 ± 0.02. The short novelty of Psidium guajava (guava) lies in its potential relevance to human health, as it has been found to possess bioactive compounds with various medicinal properties, such as antimicrobial, antioxidant, and anti-inflammatory activities, making it a promising natural resource for therapeutic applications. [ABSTRACT FROM AUTHOR]

Nonessential heavy metals are toxic to human health. In this study, mercury, a hazardous metal, was detected by colorimetric analysis using Zingiber (Z.) officinale. The eco-friendliness of this method was also emphasized. The ultraviolet (UV) spectrum is a broad peak observed at 200-250 nm in Z. officinale leaf extracts. The UV spectrum of green synthesized Z. officinale exhibited an absorption band of 286 nm, which confirms the nanoparticle (NP) synthesis. Fourier transform infrared (FTIR) analysis of the vibrational peak around 3307 cm-1 is assigned to v(O-H) stretching that could possibly emanate from carbohydrates or phenolics. The peaks found around 2917 and 2849 cm-1 are ascribed to the -C-H stretch of the alkyl group, and the peak around 1625 cm-1 is due to the enolic ß-diketones or -C = O stretch of carboxylic acids, while the corresponding -C-O stretch is observed around 1375 and 1029 cm-1. The assignment of peaks is similar. It is clear from the scanning electron microscope (SEM) image that the constituent parts were nonuniform, sphere-shaped, agglomerated, and of an average size of 30.9 nm. X-ray diffraction (XRD) analysis was used to determine the structural characteristics and crystalline nature of Z. officinale. The observed intensity peaks at 32.35°, 36.69°, 39.24°, 44.76°, 59.42°, and 67.35° are, respectively, of the Z. officinale diffraction 2 values, which correspond to the standard database values. The synthesized copper NPs synthesized tested antibacterial properties against various strains of microorganisms, including Escherichia coli: 25 µg/mL 2.01 ± 0.11 and 100 µg/mL 5.37 ± 0.12, Staphylococcus (S.) aureus: 25 µg/mL 1.05 ± 0.71 and 100 µg/mL 11.43 ± 1.27, Streptococcus mutans: 25 µg/mL 02.01 ± 0.1 and 100 µg/mL 15.67 ± 0.17, and Enterococcus faecalis: 25 µg/mL 03.11 ± 0.7 and 100 µg/mL 18.32 ± 0.2. The short novelty of Z. officinale lies in its potential relevance to human health, as it has been found to possess bioactive compounds with various medicinal properties, such as antimicrobial, antioxidant, and anti-inflammatory activities, making it a promising natural resource for therapeutic applications. [ABSTRACT FROM AUTHOR]

Background: Nonessential heavy metals pose a significant threat to human health due to their toxicity. Mercury, in particular, is identified as a hazardous metal. The study aims to detect mercury using colorimetric analysis with Murraya koenigii, emphasizing the eco-friendliness of the method. Aims and Objectives: The primary objective is to detect mercury using a colorimetric analysis method employing Murraya koenigii. Additionally, the study aims to investigate the eco-friendliness of this detection method. Materials and Methods: Colorimetric analysis was conducted using Murraya koenigii to detect mercury. Ultraviolet-visible (UV-vis) spectroscopy was employed to detect the formation of silver nanoparticles (AgNPs), with a characteristic surface plasmon resonance (SPR) band observed. X-ray diffraction (XRD) data analysis was performed to determine the crystalline nature and size of AgNPs. Scanning electron microscopy (SEM) was utilized to visualize the morphology of AgNPs. Fourier transform infrared (FTIR) spectroscopy was employed to identify functional groups involved in reducing silver ions. Antibacterial properties of synthesized AgNPs were tested against various microorganisms, including Escherichia coli, Staphylococcus aureus, Streptococcus mutans, and Enterococcus faecalis. Results: Mercury was successfully detected using colorimetric analysis with Murraya koenigii. Formation of AgNPs was confirmed by UV-vis spectroscopy, with a characteristic SPR band at 418 nm. AgNPs were found to be crystalline with an average size of 5.20 nm, as determined by XRD analysis. SEM images revealed spherical and polycrystalline AgNPs. FTIR spectra indicated the involvement of the -OH group of compounds in the extract in reducing silver ions. Synthesized AgNPs exhibited antibacterial properties against various microorganisms. Conclusion: A sustainable and eco-friendly method for synthesizing AgNPs using Murraya koenigii extract was successfully developed. This method not only detected mercury but also demonstrated antibacterial properties against various microorganisms. The study underscores the health implications of nonessential heavy metals, emphasizing the importance of eco-friendly detection and mitigation methods. [ABSTRACT FROM AUTHOR]

Nanotechnology is developing into a fast-expanding discipline with applications in science and technology, and nanostructures are a crucial research tool in many fields. Due to their remarkable electrical, optical, magnetic, catalytic, and pharmacological capabilities, metal and metal oxide nanoparticles (NPs) have drawn study interest. Natural elements (plants, microorganisms, fungi, etc.) are utilized in a chemical-free, environmentally benign way to synthesize metals and metal oxides. The optical, electrical, and antimicrobial qualities of silver nanoparticle (AgNP) make them a popular choice. More than 200 active ingredients, including water-soluble, organic-soluble, and volatile chemicals, are found in Ganoderma. The main components are polysaccharides, adenosine, and terpenoids, each of which has exceptional therapeutic properties. This article explains the synthesis of Ag NPs by Ganoderma lucidum and tests the antibacterial effectiveness for use in biological applications. [ABSTRACT FROM AUTHOR]

Nano-coating of orthodontic brackets with a combination or hybrid of metals and metal oxides may reduce the streptococcus mutans count and incidence of enamel decalcification seen around brackets in patients undergoing fixed orthodontic treatment. In total, 255 orthodontic brackets (3M Unitek, Monrovia, California, USA) were divided into one control group (group I) of 60 and three experimental groups of 65 each (groups II, III, and IV). The experimental group brackets were coated with a combination of silver-zinc oxide, copper oxide -zinc oxide, and silver-copper oxide nanoparticles using physical vapour deposition method. The two nanoparticles used for each group were mixed in the ratio of 1:1 by weight for providing a uniform hybrid coating. Sixty brackets from each group were used for microbiological evaluation of antibacterial activity against Streptococcus mutans in blood agar medium, and the remaining five brackets from each experimental group were used for SEM analysis to check the uniformity of the coating. Nano-coated brackets demonstrated better antibacterial properties than uncoated brackets. Copper oxide-zinc oxide nanoparticles coated brackets demonstrated better antibacterial properties than the silver-zinc oxide and silver-copper oxide coated brackets. [ABSTRACT FROM AUTHOR]

Aim: The current work intends to examine the antibacterial activity of silver nanoparticles (AgNPs) mediated by Ocimum gratissimum stem extract against wound infections. Materials and Methods: To evaluate the membrane damage brought on by AgNPs, analyses of cytoplasmic leakage and protein leakage assays were performed. Results: The outcomes demonstrated that all of the tested bacterial strains were significantly resistant to the AgNPs' antibacterial activity. AgNPs damaged membranes and caused cellular contents to leak in the target pathogens, according to an examination of protein and cytoplasmic leakage. Conclusion: According to the current investigation, AgNPs mediated by Ocimum gratissimum stem extract may be effective antibacterial agents against microorganisms that cause wounds. [ABSTRACT FROM AUTHOR]

Background: To assess and contrast the depth of penetration of conventional calcium hydroxide, nanoparticle calcium hydroxide, silver nanoparticles, and combination of nanoparticle calcium hydroxide and silver nanoparticles into dentinal tubules using confocal laser scanning microscope. Materials and Methods: Eighty human single-rooted teeth were decoronated and instrumented up to Protaper Universal F3. Teeth were separated into four groups at random (n = 20) following chemomechanical preparation. Group 1: Control Conventional Calcium Hydroxide; Group 2: Nanoparticle Calcium Hydroxide; group 3: Silver Nanoparticles; group 4: Combination of Nanoparticle Calcium Hydroxide and Silver Nanoparticles. With the use of lentulo spirals, medications were injected into the canals, stirred up with ultrasound, and then kept at 37°C for 24 hours. A 1 mm thick slice was obtained at 5 mm from the root apex by sectioning the root perpendicular to the long axis of the tooth and then put on a glass slide to measure the depth of penetration using a confocal laser microscope. Statistical Analysis: To quantify the depth of penetration among the four groups, a one-way ANOVA was used and post hoc-Tukey's test was used to compare between groups. Results: All of the groups were statistically significant, with group 4 showing the greatest depth of penetration, followed by group 2 and group 3. In contrast, all other groups in the intergroup comparison were statistically significant (P value 0.05) aside from the comparison of group 2 to group 3. Conclusion: Silver nanoparticles and nanoparticle calcium hydroxide together demonstrated greater penetration than calcium hydroxide, silver nanoparticles, and nanoparticle calcium hydroxide alone. [ABSTRACT FROM AUTHOR]

Investigating the application of innovative antimicrobial surface coatings on medical devices is an important field of research. Many of these coatings have significant drawbacks, including biocompatibility, coating stability and the inability to effectively combat multiple drug-resistant bacteria. In this research, we developed an antibiofilm surface coating for medical catheters using biosynthesized silver nanoparticles (b-Cs-AgNPs) developed using leaves extract of Calliandra surinamensis. Various characterization techniques were employed to thoroughly characterize the synthesized b-Cs-AgNPs and c-AgNPs. b-Cs-AgNPs were compatible with human normal kidney cells and chicken embryos. It did not trigger any skin inflammatory response in in vivo rat model. b-Cs-AgNPs demonstrated potent zone of inhibition of 19.09 mm when subjected to the disc diffusion method in E. coli confirming strong antibacterial property. Different anti-bacterial assays including liquid growth curve, colony counting assay, biofilm formation assay supported the potent antimicrobial efficacy of b-Cs-AgNPs alone and when coated to medical grade catheters. Mechanistic studies reveal the presence of ferulic acid, that was important for the synthesis of b-AgNPs along with enhanced antibacterial effects of b-Cs-AgNPs compared to c-AgNPs, supported by molecular docking analysis. These results together demonstrated the effective role b-Cs-AgNPs in combating infections and mitigating biofilm formations, highlighting their need for further study in the field of biomedical applications. Schematic Illustration of Eco-Friendly Synthesis for Biofilm Prevention on Medical Catheters and Bacterial Infection Mitigation. Created with BioRender.com. [ABSTRACT FROM AUTHOR]

Objectives: This study aimed to report a simple environmentally compatible method that is economically affordable for the facile biosynthesis of stable silver nanoparticles (AgNPs) in corn steep liquor (CSL) nutrient using the sewage of a leather factory. Materials and Methods: The biosynthesis of AgNPs were done by reduction of AgNO3 in the sewage of leather factory as a mixed bacterial culture and corn steep liquor under anaerobic condition while protecting from light. Results: The AgNPs were found to have a characteristic absorption peak at 416 nm on the ultraviolet-visible spectrum. Characterization of AgNPs was performed by x-ray diffraction (XRD) and Fourier-transform infrared (FTIR). The scanning electron microscopy (SEM) and transmission electron microscopes (TEM) images showed poly-dispersed spherical stable AgNPs with a maximum diameter of 20 nm. Moreover, the dynamic light scattering (DLS) showed that the average size of AgNPs was 15.57 nm with a zeta potential value of -19.2 mV. The synthesized nanoparticles demonstrated more antibacterial activity in opposition to gram-negative bacteria. The zone of inhibition of biosynthesized AgNPs in 1 mM concentration of AgNO3 against Escherichia coli was equal to that of gentamicin. Conclusions: The interaction of protein residues with AgNPs was identified, supporting that the proteins not only act as a reducing agent but also as a capping. The synthesized AgNPs showed antibacterial activity, providing commercial viability in biomedicine. [ABSTRACT FROM AUTHOR]

Objective(s): Concerns regarding increased breast cancer cases worldwide have spurred interest in the discovery of novel approaches to overcome this deadly disease. Although several treatment strategies have been developed to treat breast cancer including chemotherapy, an efficient drug delivery system remains a challenge. Here, we study the drug distribution and boosting the efficiency of Panobinostat, a histone deacetylase inhibitor, by using silver nanoparticles as a controlled drug delivery system. Materials and Methods: Green synthesis of silver nanoparticles, as nanocarriers for drug delivery was synthesized by using Rhazya stricta extract and loaded with the drug. These drug-loaded nanoparticles were characterized by UV-vis spectroscopy, XRD, FTIR, SEM, and EDX techniques. Results: The AgNPs had an average size of 20 nm and were stable over a period. The evaluation of drug encapsulation effectiveness and drug release capacity revealed 56% encapsulation efficiency and sustained drug release. The kinetics study of drug release showed the first-order reaction which means that drug concentration is proportional to drug release. The MTT assay showed that drug-loaded AgNPs had a potent and dose-dependent anticancer activity on the breast cancer cell lines (MDA-MB-231). Conclusion: As the successfully green synthesized Panobinostat-AgNPs were stable and exhibited increased in vitro anticancer activity compared with free Panobinostat, our data demonstrate that the combination of AgNPs with Panobinostat improves the drug's long-term viability, effectiveness, and active targeting as a potential targeted therapeutic molecule for the treatment of cancer. To strengthen the utilization of this combination therapy in cancer therapy trials, further research is warranted in vivo. [ABSTRACT FROM AUTHOR]

Silver-based antibacterial coatings limit the spread of hospital-acquired infections. Indeed, the use of silver and silver oxide nanoparticles (Ag and AgO NPs) incorporated in amorphous hydrogenated carbon (a-C:H) as a matrix demonstrates a promising approach to reduce microbial contamination on environmental surfaces. However, its success as an antibacterial coating hinges on the control of Ag+ release. In this sense, if a continuous release is required, an additional barrier is needed to extend the release time of Ag+. Thus, this research investigated the use of a plasma fluoropolymer (CFx) as an additional top layer to elongate Ag+ release and increase the antibacterial activity due to its high hydrophobic nature. Herein, a porous CFx film was deposited on a-C:H containing Ag and AgO NPs using pulsed afterglow low pressure plasma polymerization. The chemical composition, surface wettability and morphology, release profile, and antibacterial activity were analyzed. Overall, the combination of a-C:H:Ag (12.1 at. % of Ag) and CFx film (120.0°, F/C = 0.8) successfully inactivated 88% of E. coli and delayed biofilm formation after 12 h. Thus, using a hybrid approach composed of Ag NPs and a hydrophobic polymeric layer, it was possible to increase the overall antibacterial activity of the coating. [ABSTRACT FROM AUTHOR]

Here, the room temperature deposition of silver (Ag) nanoparticles (NPs) on silicon (Si) substrate has been carried out by a simple chemical route to investigate their elastic and micro-structural properties. The theoretical X-ray peak profile analysis has been pursued through the Scherrer model, modified Scherrer model, modified Williamson–Hall model, size–strain plot model and Halder–Wagner model. The X-ray diffraction (XRD) analysis results in the crystalline nature of Ag NPs having nearer dodecahedron structure. The parameters including micro-strain, internal stress and energy density have been estimated for all reflection peaks of XRD. The findings show that the nano-crystalline size (NCS) estimated from all models is in reasonably good agreement. This analysis can pave the way for novel research avenues by comparing the estimated elastic and micro-structural properties of Ag NPs as a potential alternative tool to existing characterization techniques and helpful in fabricating different sizes of Ag–Si nanostructure-based gas-sensing devices. The influence of Ag nanoparticles on Si nanowire towards acetone gas sensor has been studied and achieved remarkable sensitivity 98.77% at 5 MHz frequency with operating temperature at 50 °C. [ABSTRACT FROM AUTHOR]

The growing resistance of bacteria to antibiotics is one of the main public health problems nowadays. The influence of silver nanoparticle (AgNP) pretreatment of 220 cows with mastitis on the susceptibility of Staphylococcus epidermidis bacteria to 31 antibiotics was studied. The obtained results were compared with the previous results for Escherichia coli, Streptococcus dysgalactiae, and Staphylococcus aureus. For all four bacteria, an increase in susceptibility (9.5–21.2%) to 31 antibiotics after cow treatment with AgNPs was revealed, while after first-line antibiotic drug treatment as expected, the susceptibility decreased (11.3–27.3%). These effects were explained by (1) the increase in the contribution of isolates with efflux effect after antibiotic treatments and its decrease after AgNP treatment and (2) the changes in bacteria adhesion and anti-lysozyme activity after these treatments. The effect of the increasing antibacterial activity of antibiotics after AgNP treatment was the most pronounced in the case of E. coli and was minimal in the case of S. epidermidis. With AgNP treatment, the time of recovery decreased by 26.8–48.4% compared to the time of recovery after treatment with the first-line antibiotic drugs. The AgNP treatment allows for achieving the partial restoration of the activity of antibiotics. [ABSTRACT FROM AUTHOR]

Co-exposure to noise and nanomaterials, such as silver nanoparticles (Silver-NPs), is a common occurrence in today's industries. This study aimed to investigate the effects of exposure to noise and the administration of silver-NPs on the liver tissue of rats. Thirty-six adult male albino Wistar rats were randomly divided into six groups: a control group (administered saline intraperitoneally), two groups administered different doses of Silver-NPs (50 mg/kg and 100 mg/kg, 5 days a week for 28 days), two groups exposed to noise in addition to Silver-NPs (at the same doses as mentioned before), and a group exposed only to noise (104 dB, 6 hours a day, 5 days a week for 4 weeks). Blood samples were taken to assess hepatic-functional alterations, such as serum ALP, ALT, and AST levels. Additionally, biochemical parameters (MDA, GPX, and CAT) and the silver concentration in the liver were measured. Histopathological analysis, mRNA expression (P53 and NF-κB), protein expression (CYP450), and liver weight changes in rats were also documented. The study found that the administration of Silver-NPs and exposure to noise resulted in elevated levels of ALP, ALT, AST, and MDA (p <.01). Conversely, GPX and CAT levels decreased in all groups compared with the control group (p <.0001). There was a significant increase (p <.05) in liver weight and silver concentration in the liver tissues of groups administered Silver-NPs (50 mg/kg) plus noise exposure, Silver-NPs (100 mg/kg), and Silver-NPs (100 mg/kg) plus noise exposure, respectively. The expression rate of P53, NF-κB, and cytochromes P450 (CYPs-450) was increased in the experimental groups (p <.05). These findings were further confirmed by histopathological changes. In conclusion, this study demonstrated that exposure to noise and the administration of Silver-NPs exacerbated liver damage by increasing protein and gene expression, causing hepatic necrosis, altering biochemical parameters, and affecting liver weight. [ABSTRACT FROM AUTHOR]

The increase in the resistance of microorganisms to existing antibiotics associated with their ability to survive in biofilms makes the development of new antimicrobial agents a topical question. Of great interest in this field are nanocomposites based on halloysite and silver nanoparticles, since they have a broad antimicrobial activity and can reduce the toxic effects of nanoparticles. In this study, we assessed the effect of the AgHNT nanocomposite at a concentration of 0.5 mg/ml on the pathogenicity factors of Serratia marcescens. The antibiofilm activity of AgHNT was assessed by resazurin assay, and visualized using light and AFM microscopy. AgHNT were found to significantly inhibit biofilm formation in S. marcescens. Although the silver-containing species did not affect protease activity, they greatly reduced the production of prodigiosin, another quorum-sensing factor, by bacteria. The AgHNT nanocomposite was more efficient in suppressing S. marcescens biofilms than the antibiotic streptomycin. [ABSTRACT FROM AUTHOR]

Silver nanoparticles (AgNPs) are substances with a wide range of uses. Utilizing extracts obtained from the peels of Rheum ribes L. (Rr) fruit growing in Erzurum region, silver nanoparticles were rapidly created in this study with a quick, easy, and environmentally friendly technique without harmful processes. In order to evaluate the attributes of the synthesized Rr-AgNPs, FE-SEM or TEM micrographs were utilized to characterize their morphology. A UV-visible spectrophotometer was used to assess the highest absorbance bands of RR-AgNPs. These data were used to define RR-AgNPs, which were characterized as having exclusively negative surface charges of -25 mV, spherical shape, maximum absorbance at 428 nm wavelength, and 96 nm size distribution. The effectiveness of the produced AgNPs for use in medical applications was assessed using the MTT technique with microdilution. Minimum inhibition concentrations of Rr-AgNPs for pathogen strains ranged from 0.03 to 0.50 mg/L. Additionally, it was discovered that AgNPs effectively suppressed malignant cells, with rates of 86.27%, 74.67%, and 73.49%, in the investigation of the anticancer effects of AgNPs. Healthy cells were not subject to any inhibitory effects at the same concentrations. [ABSTRACT FROM AUTHOR]

The development of an effective and eco-friendly silver nanoparticle (AgNPs) to abate the effect of abiotic stress is an important area of nano-biotechnology. This study aimed to study the priming effect of plant-based green-synthesized silver nanoparticles and melatonin on the physiological and biochemical activities of drought-stressed E. uniflora. Sterilized seeds of E. uniflora were primed with 0.06 mg/l of ML-AgNPs, 0.06 mg/l of melatonin, and a nano-silver formulation of melatonin (1:1). Primed seeds were planted and subjected to 7 days under drought stress. The ML-AgNPs enhanced germination percentage, speed and vigor, and shoot elongation and induced the production of APx, CAT, and proline dehydrogenase (100% increases). Melatonin improved the activities of APx and CAT, total protein, accumulation of proline, and proline dehydrogenase (200% increases) and stabilized MDA content. Meanwhile, silver nano-formulation of melatonin increased leaves proliferation of leaves and production of APx, GPx, SOD, and CAT. Accumulation of proline and 100% upregulation of proline dehydrogenase osmo-regulated the effects of the drought, reduced MDA contents, and stabilized the excessive production of H2O2 and O2−. The ML-AgNO3 showed an efficient delivery system of melatonin into the plant under drought stress. As a result, our research shows that melatonin in silver nano-formulation (1:1) is a useful biostimulant against drought stress. [ABSTRACT FROM AUTHOR]

Synthetic dyes are persistent organic environmental pollutants that can cause extensive damage to living beings and to the ecosystem as a whole. Cost-effective, sustainable, and efficient strategies to deal with this type of pollution are necessary as it commonly resists conventional water treatment methods. Silver nanoparticles (AgNPs) synthesized using the aqueous extract from the leaves, stem, and fruits of Leucaena leucocephala (Leucena) were produced and characterized through UV–vis, TEM, EDS, SDL, XPS, XRD, and zeta potential, and they proved to be able to promote adsorption to remediate methylene blue and tartrazine pollution in water. The nanoremediation was performed and did not require direct exposure to sunlight or any special lamp or a specific reduction agent. The AgNPs produced using the extract from the leaves exhibited the best performance in nanoremediation and also presented antioxidant activity that surpassed the one from butylated hydroxytoluene (BHT). Consequently, it is an interesting nanotool to use in dye nanoremediation and/or as an antioxidant nanostructure. [ABSTRACT FROM AUTHOR]

The advent of Surface-Enhanced Raman Scattering (SERS) has enabled the exploration and detection of small molecules, particularly in biological fluids such as serum, blood plasma, urine, saliva, and tears. SERS has been proposed as a simple diagnostic technique for various diseases, including cancer. Renal cell carcinoma (RCC) ranks as the sixth most commonly diagnosed cancer in men and is often asymptomatic, with detection occurring incidentally. The onset of symptoms typically aligns with advanced disease, aggressive histology, and unfavorable prognosis, and therefore new methods for an early diagnosis are needed. In this study, we investigated the utility of label-free SERS in urine, coupled with two multivariate analysis approaches: Principal Component Analysis combined with Linear Discriminant Analysis (PCA-LDA) and Support Vector Machine (SVM), to discriminate between 50 RCC patients and 44 healthy donors. Employing LDA-PCA, we achieved a discrimination accuracy of 100% using 13 principal components, and an 88% accuracy in discriminating between different RCC stages. The SVM approach yielded a training accuracy of 100%, a validation accuracy of 99% for discriminating between RCC and controls, and an 80% accuracy for discriminating between stages. The comparative analysis of raw and normalized SERS spectral data shows that while raw data disclose relative concentration variations in urine metabolites between the two classes, the normalization of spectral data significantly improves the accuracy of discrimination. Moreover, the selection of principal components with markedly distinct scores between the two classes serves to alleviate overfitting risks and reduces the number of components employed for discrimination. We obtained the accuracy of the discrimination between the RCC patients cases and healthy donors of 90% for three PCs and a linear discrimination function, and a 88% accuracy of discrimination between stages using six PCs, mitigating practically the risk of overfitting and increasing the robustness of our analysis. Our findings underscore the potential of label-free SERS of urine in conjunction with chemometrics for non-invasive and early RCC detection. [ABSTRACT FROM AUTHOR]

Early detection of diseases can increase the chances of successful treatment and survival. Therefore, it is necessary to develop a method for detecting or sensing biomolecules that cause trouble in living organisms. Disease sensors should possess specific properties, such as selectivity, reproducibility, stability, sensitivity, and morphology, for their routine application in medical diagnosis and treatment. This work focuses on biosensors in the form of surface-functionalized gold (AuNPs) and silver nanoparticles (AgNPs) prepared using a less-time-consuming, inexpensive, and efficient synthesis route. This allows for the production of highly pure and stable (non-aggregating without stabilizers) nanoparticles with a well-defined spherical shape, a desired diameter, and a monodisperse distribution in an aqueous environment, as confirmed by transmission electron microscopy with energy-dispersive X-ray spectroscopy (TEM-EDS), X-ray diffraction (XRD), photoelectron spectroscopy (XPS), ultraviolet-visible (UV-VIS) spectroscopy, and dynamic light scattering (DLS). Thus, these nanoparticles can be used routinely as biomarker sensors and drug-delivery platforms for precision medicine treatment. The NPs' surface was coated with phosphonate dipeptides of L-leucine (Leu; l-Leu–C(R1)(R2)PO3H2), and their adsorption was monitored using SERS. Reproducible spectra were analyzed to determine the orientation of the dipeptides (coating layers) on the nanoparticles' surface. The appropriate R2 side chain of the dipeptide can be selected to control the arrangement of these dipeptides. This allows for the proper formation of a layer covering the nanoparticles while also simultaneously interacting with the surrounding biological environment, such as cells, tissues, and biological fluids. [ABSTRACT FROM AUTHOR]

This article deals with the antibacterial and anticancer potential of secondary metabolites produced by actinomycetes also reported as actinobacteria, Microbacterium proteolyticum (MN560041), and Streptomycetes rochei, where preliminary studies were done with the well diffusion method. These actinobacteria's silver nanoparticles were synthesized and characterized using transmission electron microscopy (TEM) and UV‐Visible spectroscopy. Anticancer was measured using the MTT test, reactive oxygen species (ROS) generation measured with DCFDA, mitochondrial membrane potential (MMP) measurement, and DAPI fluorescence intensity activity was measured in treated and non‐treated cancerous cells. The IC50 value for 5‐FU (a), LA2(O) (b), LA2(R) (c), LA2(ON) (d), and LA2(RN) (e) was obtained at 3.91 μg/mL (52.73% cell viability), 56.12 μg/mL (52.35% cell viability), 44.90 μg/mL (52.3% cell viability), 3.45 μg/mL (50.25% cell viability), and 8.05 μg/mL (48.72% cell viability), respectively. TEM micrographs revealed discrete, well‐separated AgNPs particles of size 7.88 ± 2 to 12.86 ± 0.24 nm. Gas chromatography‐mass spectrometry was also performed to detect the compounds in bioactive metabolites where n‐hexadecanoic acid was obtained as the most significant one. MTT test showed a substantial decline in A549 cell viability (up to 48.72%), 2.75‐fold increase in ROS generation was noticed in comparison to untreated A549 lung cancer cells when measured with DCFDA. A total of 0.31‐fold decrease in MMP and 1.74‐fold increase in DAPI fluorescence intensity compared to untreated A549 lung cancer cells suggests that the synthesized nanoparticles promote apoptosis in cancerous cells. Our findings suggests that the secondary metabolites of M. proteolyticum and S. rochei in nanoparticle form can be used as a significant compound against lung cancers. Significance statement: The current study has shown that these novel and rare actinobacteria Microbacterium proteolyticum and Streptomycetes rochei can produce a wide range of bioactive compounds which could serve as potential sources for future anticancer drug development. [ABSTRACT FROM AUTHOR]

Photochemical reduction is used to develop many methods of creating biologically active substances and materials consisting of silver nanoclusters, which makes them relevant for science and technology, including different trends in biotechnology, catalytic systems, label-free quantification, metasurfaces and nanohybrid composites. The paper presents the silver nanoparticle (AgNP) technology based on cavitation-diffusion photochemical reduction in the presence of 10 mg of ligand (polyvinylpyrrolidone) allowing to significantly change the AgNP content depending on the concentration of silver nitrate (AgNO3) in the reaction system, and providing the AgNP domination having a certain size. It is found that at 5 mg of AgNO3 in the reaction system, the size of at least 60% of synthesized nanoparticles, is 26 nm or more, while at 2.5 mg of AgNO3, up to 94.7% of nanoparticles have the size of 15 nm and less, 6 to 10 nm AgNPs being dominated. This meets the need for AgNPs of a certain the size in different fields of science and technology, including medical and pharmaceutical industries, agriculture, and laboratory diagnostics. [ABSTRACT FROM AUTHOR]

Formation of Ag nanoparticles in the PbO–Bi 2 O 3 –Ga 2 O 3 heavy metal oxide glasses modified by addition of Ag 2 O and Sb 2 O 3 was monitored using electrical and optical measurements. Electrical measurements are suitable for this purpose as they are very sensitive to any changes in the arrangement of the material structure. The formed spherical silver nanoparticles were studied by a high-resolution transmission electron microscopy (HRTEM), their nature was confirmed by selected area electron diffraction analysis (SAED) and x-ray photoelectron spectroscopy (XPS). We demonstrated and documented that the samples containing Ag/Sb change during additional heating (in the investigated temperature range of 240–290 °C) – the electrical conductivity changes and also the relaxation time as established by electrical modulus measurements changes. The behaviour of the base glass without Ag/Sb addition remains practically unaffected by the same additional heating. TEM confirmed an increased number of spherical nanoparticles as a consequence of heat treatment. The indexes of the SAED pattern match the fcc-Ag crystalline phase, HRTEM identified the periodical arrangement in these particles to correspond to d-spacing of (111) planes in Ag and the elemental state of the present Ag in the heat-treated sample was confirmed also by XPS. [ABSTRACT FROM AUTHOR]

Background: Soybean rust caused by Phakopsora pachyrhizi Syd. is one of the major constraints in the production of soybean. Nanotechnology is a new scientific approach that includes use of materials and equipment capable of using physical and chemical properties of a substance at molecular level to explore the biological and material worlds in nanometer-scale and use it in various carriers from medicine to agriculture. Nanotechnology has emerged as one of the most innovative scientific field in agriculture. Among various synthesis methods, green synthesis of nanoparticles is widely used by researchers because it is simple, convenient, eco-friendly and requires less reaction time. Methods: The chitosan based zinc oxide nanoparticles (Ch-ZnONPs), pomegranate aril based sulphur nanoparticles (PA-SNPs) and pomegranate aril based silver nanoparticles (PA-AgNPs) were synthesised, characterised and evaluated under in vitro conditions against soybean rust pustules. Result: The maximum per cent spore inhibition of 70.25, 74.70 and 86.68 per cent over control was recorded in Ch-ZnONPs (1250 ppm), PA-SNPs (2000 ppm) and PA-AgNPs (500 ppm) respectively. [ABSTRACT FROM AUTHOR]

Nanobiotechnology has evolved as a promising technology in developing therapeutically active materials. This study involved the biological synthesis of silver nanoparticles (AgNPs) from extracellular filtrate from the fungal species Aspergillus fumigatus to assess their antioxidant and cytotoxic activity under in‐vitro conditions. This method has become more reliable than physical and chemical approaches, attributed to its use of ecologically clean and non‐toxic methods. These synthesized nanoparticles are then characterized by UV–visible spectroscopy, Fourier transform infrared spectroscopy (FTIR), dynamic light scattering, scanning electron microscope (SEM), differential scanning calorimetry, and X‐ray diffraction (XRD). Design optimization was done to optimize the selected variables to choose the best‐fit ratios for the experiment. UV spectroscopy showed the absorption peaks for AgNPs and bovine serum albumin (BSA) AgNPs at 300 and 315 nm. FTIR spectroscopy showed amide, carboxyl, and ester groups in BSA AgNPs, indicating their role in stabilizing nanoparticles. The particle size and zeta potential for AgNPs and BSA AgNPs were found to be 124.81 and 152.92 nm; zeta potentials for AgNPS and BSA AgNPs were found to be −13.3 and −15.6 mV. Various antioxidant studies like 2,2‐Diphenyl‐1‐picrylhydrazyl (DPPH), 2,2‐azinobis‐(3‐ethylbenzothiazoline‐6‐sulfonate) (ABTS), ion chelating assay, lipid peroxide assay, and malondialdehyde were carried out, indicating good antioxidant activity for synthesized nanoparticles. SEM images advocated good spherical images and are well dispersed. The cytotoxic assay performed on HT‐29 colon cancer cells exhibited good inhibition activity for AgNPs and BSA AgNPs, with an IC50 value of 120 and 100 μg/ml. These study results revealed that the synthesized AgNPs, on optimization through Box‐Behnken design, exhibited good antioxidant and cytotoxic activity. [ABSTRACT FROM AUTHOR]

Silver nanoparticles (AgNPs) have a primordial role in the nanotechnology industry since they have great antimicrobial effects against diverse pathogens. AgNP production, use, and discard have been increasing; still, there is debate about the consequences of exposure to AgNPs for animals and humans. The bioaccumulation and toxicity of AgNPs depend on several factors, including AgNP concentration, physicochemical characteristics, and aggregation. So, complete activity and toxicity profiles for each silver nanoparticle synthesized must be performed. The present work aimed to characterize the behavior of specific AgNPs, then crossover of their antimicrobial capacity against Pseudomonas aeruginosa and Staphylococcus aureus with their potential in vitro cytotoxic effects in murine fibroblasts (3T3) and human keratinocytes (HaCat) cell lines, and in vivo general and organ‐specific toxicity in zebrafish embryos and larvae. A high susceptibility of P. aeruginosa and S. aureus to low concentrations of AgNPs was observed, yet a cytotoxic effect was also detected in 3T3 and HaCat cells. Moreover, these concentrations delayed embryonic development in zebrafish embryos and presented morphological abnormalities, neurotoxicity, and cardiotoxicity in zebrafish larvae. The results highlight the importance of jointly evaluating the antimicrobial activity and the toxicological profile of each nanoparticle manufactured; this study presents a suitable platform for such crossover assessment. [ABSTRACT FROM AUTHOR]

Biosynthesized silver nanoparticles (AgNPs) are widely used in varied applications, which are morphology dependent. Consequently, a morphology-controlled synthesis is mandatory. Although there are several studies focused on the plant extract-based biosynthesis of metallic nanoparticles, the use of extracts obtained from agro-wastes is scant. Furthermore, information regarding morphology modification through the use of additional agents is even more scarce. Thus, in this study, AgNPs were synthesized using a malt extract (ME) obtained from an artisanal beer brewing process residue. Additionally, sodium chloride (NaCl), gum arabic (GA), and talc (T) were used in an attempt to modify the morphology of AgNPs. XRD, DLS, SEM, and TEM results demonstrate that stable AgNPs of different sizes and shapes were synthesized. FTIR, HPLC analysis, and the quantification of total proteins, free amino acids, reducing sugars, and total polyphenols before and after AgNPs synthesis showed that ME biomolecules allowed them to act as a source of reducing and stabilizing agents. Therefore, this study provides evidence that ME can be successfully used to biosynthesize AgNPs. Additionally, the antibacterial activity of AgNPs against Gram-negative and Gram-positive bacteria was evaluated. Results indicate that AgNPs show a higher antibacterial activity against Gram-positive bacteria. [ABSTRACT FROM AUTHOR]

Due to their unique properties, organosols of silver nanoparticles are widely used in optical and semiconductor devices, to produce electrically and thermally conductive films, as catalysts, antibacterial materials, etc. This work proposes a simple and highly productive method for the preparation of silver organosols, which have a metal concentration as high as 1800 g/L and contain spherical nanoparticles with low polydispersity and a median size of 9.1 nm. The method consists in the initial preparation of silver nanoparticle hydrosols with a concentration of higher than 30 g/L followed by the transfer of the NPs into an organic phase of o-xylene. A set of physical research methods has been employed to study the regularities of the extraction of silver nanoparticles with o-xylene in the presence of cetyltrimethylammonium bromide (CTAB) and ethanol and to determine the optimal process conditions, under which the extraction degree is as high as 62.5%. It has been found that bromine anions contained in CTAB molecules cause the aggregation of some amount of silver nanoparticles with the formation of silver metal sediment in the aqueous phase. According to X-ray photoelectron spectroscopy data, the sediment contains bromide ions (up to 4 at %) on the particle surface. Organosols synthesized under optimal conditions are stable for more than 7 months and withstand repeated cycles of drying and redispersing. Silver organosols have been used to obtain metal films with an electrical conductivity of about 68 500 S/cm, which increases to 412 000 and 509 500 S/cm (87.8% of the electrical conductivity of bulk silver) after thermal treatment at 150 and 250°C, respectively. [ABSTRACT FROM AUTHOR]

Silver-based nanomaterials have etched an indelible mark in multiple domains. The green synthesis of silver nanoparticles has received significant attention over the last few years vis-à-vis the conventional use of toxic chemicals and reagents in the preparatory stages. In this milieu, the work reported here highlights the use of an aqueous extract of teff (Eragrostis tef) flour to prepare silver nanoparticles (TSNPs). The compositional abundance of various phytochemicals, sunlight-induced bio-reduction of silver ions, and subsequent stabilization of the nanostructures by teff’s biomolecules were adroitly exploited. UV-visible spectroscopic analysis was employed to track the evolution of the TSNPs over time and their month-long storage stability. Exhibiting λmax at around 426 nm and energy gap (as revealed by Tauc’s plot) of 2.26 eV, the silver nanomaterial was employed for methylene blue dye degradation (50% degradation in less than 20 min) and DPPH scavenging (IC50 = 243.42 μL containing 410 μg of TSNPs), attesting their catalytic and anti-oxidant potency. On the other hand, anticoagulant action and a concentration-dependent variation were noted for radicle length post germination of Cicer arientinum seeds, treated with the TSNPs. The TSNPs could have profound implications in multiple domains. [ABSTRACT FROM AUTHOR]

The green synthesized silver nanoparticles (AgNPs) with the aqueous extract of the leaves of household vegetable, Trigonella foenumgraecum were characterized and tested for their anti-oxidant and anti-bacterial efficacy with sixteen human clinical isolates. The Formation of AgNPs was confirmed with the surface plasmon spectra of the dark brown solution centered at 448 nm. The Particle size calculated with XRD data was 41.23 nm and the SEM size ranged between 52.56 nm and 80.51 nm. The presence of -NH and -OH groups that effectively react and reduce Ag+ ions to Ag0 was evident from the FT-IR spectra. The particles are predominantly spherical in shape and varied from 5 to 80 nm in size. As Suggested from the analysis by SEM and TEM, majority of them fall between 5 nm and 20 nm. A composite solution of AgNPs with polyvinyl alcohol (PVA) was electrospun into films and tested on 8 human clinical isolates including methicillin-resistant Staphylococcus aureus (MRSA). The PVA-AgNP films showed enormous activity against the MRSA prompting further study as wound dressings in the Wistar albino rat model. Although the animal study was abruptly terminated owing to the pandemic-induced lock down, the preliminary study results for 9 days suggest the potential clinical applications of these wound dressings. The synthesized AgNPs with and without PVA demonstrated good anti-oxidant activity and highly significant (P = 0.001) zones of inhibition with eighteen clinical isolates were tested. [ABSTRACT FROM AUTHOR]

The aim of the experiments was to evaluate shifts in the prokaryotic and eukaryotic microbiome of maize rhizoplanes treated with five forms silver nanoparticles with different surface properties, produced by chemical reduction of silver(V) nitrate. Metagenomic studies were performed using appropriate procedures to create NGS libraries and sequences to species. All silver nanoparticles forms used moderately limited the growth of maize, without significantly affecting normalized difference vegetation indexes. Significant shifts in the taxa of the microbiome while preserving biodiversity were noted under the influence of silver nanoparticles, and the reaction of bacteria and eukaryotes was different. The eukaryotic microbiome, richer in the studied substrate, turned out to be more sensitive, showing greater qualitative and quantitative changes than the bacteriome. silver nanoparticles did not reduce the occurrence of mycorrhizal fungi, enriched the occurrence of Acidobacteriota and, with the exception of trisodium citrate reduction/sodium borohydride stabilization type, enriched the beneficial bacteria of Devosia. Within silver nanoparticles, distinct effects have been demonstrated for type with trisodium citrate reduction/sodium borohydride stabilization versus cysteamine reduction/trisodium citrate stabilization versus group: hydroxylamine hydrochloride reduction, tannic acid reduction and trisodium citrate reduction. The beneficial changes in maize rhizoplane microbiome can be attributed special to silver nanoparticles reduced using hydroxylamine hydrochloride. [ABSTRACT FROM AUTHOR]

Recently, the eco-friendly production of silver nanoparticles (AgNPs) has become a focal point for researchers. In India, the quest for cost-effective, non-hazardous compounds suitable for reducing and stabilizing AgNPs has been limited. This study explores the synthesis of AgNPs using Elettaria cardamomom seed extract. We evaluated the efficiency of silver ion (Ag+) reduction and AgNP formation from an aqueous AgNO3 solution combined with the cardamom seed extract. Characterization of the AgNPs was carried out through UV-vis spectroscopy, XRD, SEM, EDAX, and FTIR. This research presents a practical and efficient strategy for AgNP production. A formulation using readily available 1 mm aqueous AgNO3, known for its accessibility and therapeutic properties, was created with cardamom seed extract serving as both a capping and reducing agent. Within 30 minutes, the silver ions were reduced to AgNPs, resulting in a change from golden to dark brown-reddish tint. Various analytical techniques, including UV-vis spectroscopy and Fourier-transform infrared spectroscopy, were employed for characterization. This study introduces an affordable, robust, and renewable method using E. cardamomum seeds for AgNP synthesis, which is entirely eco-friendly and devoid of toxic chemicals. AgNPs hold promise for applications in cancer treatment and diagnosis, setting them apart from other noble metals. [ABSTRACT FROM AUTHOR]

Nowadays, the applications of nanotechnology are increasing in various fields such as information technology, energy, the medical sector, and agriculture. Nanotechnology has proved its ability to solve problems in agriculture and related industries. Establishing the impact of nanoparticles on various ecosystems has become a primary research topic, but studies on forest ecosystems and trees are quite limited. This study examined the effects of silver nanoparticles on the germination parameters of oriental beech seeds and established their toxic threshold values. Silver nanoparticles were applied at concentrations of 200, 400, 600, 800, and 1000 mg/L to oriental beech (Fagus orientalis) seeds collected from 10 different populations in order to identify the germination rate, germination percentage, seedling height, root collar diameter, plumula length, radicle thickness, and radicle length parameters. The results revealed that silver nanoparticles have a negative effect on germination and seedling parameters of oriental beech seeds, and that this effect is clearly seen in the germination rate at 20 mg/L levels and in seedling characters starting from 60 mg/L dose, causing a decrease of 13% in germination rate, 24% in germination percentage, 40% in plumula length, and 30% in radicle length. The Kahramanmaras-Andirin population was found to be the most affected by nanoparticles, while the Bursa-Inegol and Ordu-Akkus populations were the least affected. [ABSTRACT FROM AUTHOR]

Surface contamination by pathogenic and deteriorating microorganisms is a constant concern in the food industry. Therefore, in this study we evaluated the antimicrobial activity of silver nanoparticles (AgNPs), produced using the essential oil of Lippia origanoides Kunth and ethanolic extract of Hymenaea martiana Hayne, against bacteria used in milk processing. For this, AgNPs were synthesized and their antimicrobial activity was evaluated for minimum inhibitory and bactericidal concentrations, time-kill, interference on the biofilm, and application on the surfaces of different materials. AgNPs showed bacteriostatic and bactericidal activity against Staphylococcus aureus (ATCC 25923), Staphylococcus aureus (ATCC 33591), Escherichia coli (ATCC 25922), Salmonella enterica subsp. enterica serovar Choleraesuis (ATCC 10708), Listeria monocytogenes, Escherichia coli, Salmonella spp.,andPseudomonas aeruginosa,and interfered with biofilm formation more than with consolidated biofilms. A 1hour period was sufficient to reduce the bacterial cells, whereas a Minimum Duration for Killing (MDK) of 99% was reached after approximately 30 min. AgNPs were effective against bacteria attached to stainless steel and polyethylene, but ineffective on tile surfaces. Thus, owing to the growing microbial resistance and the need to develop new products based on the concepts of green chemistry, these AgNPs are presented as a new possibility for cleaning processes in the food industry [ABSTRACT FROM AUTHOR]

Tiwari–Das model water–Ag-based radiative nanofluid heat transfer and fluid flow features inside a square cavity with adiabatic conditions on horizontal walls and isothermal conditions on both side walls, by taking magnetic field into account, are examined numerically in this analysis. The non-linear partial differential equations representing momentum and temperature equations are evaluated numerically by utilizing a finite difference method. The sketches of isotherms and stream lines of nanofluid inside the cavity with dissimilar values of radiation parameter $ ({0.1 \le R \le 0.9}) $ (0.1 ≤ R ≤ 0.9) , Reynolds number $ ({0.1 \le \textrm{Re} \le 0.5}) $ (0.1 ≤ Re ≤ 0.5) , volume fraction parameter $ ({0.01 \le \phi \le 0.09}) $ (0.01 ≤ ϕ ≤ 0.09) , Rayleigh number $ ({100\textrm{ } \le \textrm{Ra} \le 1000}) $ (100 ≤ Ra ≤ 1000) , magnetic field parameter $ ({1.0 \le M \le 3.0}) $ (1.0 ≤ M ≤ 3.0) and Prandtl number $ ({5.2 \le \textrm{Pr} \le 7.2}) $ (5.2 ≤ Pr ≤ 7.2) are plotted through graphs. The values of dimensionless Nusselt number with various values of pertinent parameters are also examined and results are represented in terms of plots. Heat transfer rate is intensified from 6.3% to 12.4% when silver nanoparticle of volume fraction 0.05 is suspended into the water. [ABSTRACT FROM AUTHOR]

The study aims at synthesizing a simple, cost-effective, selective, and sensitive colorimetric sensor based on chlorophyll-coated silver nanoparticles (Chl-AgNPs) using microwave-assisted method for the determination of Cr(VI) ions in an aqueous medium. The characterization reveals that synthesized nanoparticles are 20–30 nm in size and spherical in shape. The presence of methyl, carboxyl, aldehyde, and ketone groups on the surface of Chl-AgNPs results in the formation of size controlled, well dispersed, and stable silver nanoparticles. The prepared nano-colloidal solution has been used for selective and sensitive determination of Cr(VI) in water samples. The addition of single drop of Chl-AgNPs solution immediately changes the color of water samples containing Cr(VI) to red displaying good sensitivity from 10 to 100 µM and high selectivity even in the presence of other metal ions. The ultraviolet–visible spectra show that in the presence of Cr(VI), the localized surface plasmon resonance (LSPR) band of Chl-AgNPs at 410 nm shifts to 470 nm with a new peak at 357 nm. Furthermore, the absorbance of the LSPR band decreases and the absorbance at 357 nm increases linearly with the concentration of Cr(VI). The functional groups on the surface of nanoparticles bind Cr(VI) on the surface leading to agglomeration and alterations in interparticle distance that are observed as changes in the color and LSPR profile. The limits of detection and quantification for Cr(VI) ions were determined to be 0.62 µM and 1.88 µM, respectively. [ABSTRACT FROM AUTHOR]

Aims To evaluate the effect of silver nanoparticles alone and in combination with Triclosan, and trans -cinnamaldehyde against Staphylococcus aureus and Escherichia coli biofilms on sutures to improve patients' outcomes. Methods and results Silver nanoparticles were prepared by chemical method and characterized by UV–visible spectrophotometer and dynamic light scattering. The minimum inhibitory concentration was assessed by the Microdilution assay. The antibiofilm activity was determined using crystal violet assay. A checkerboard assay using the fractional inhibitory concentration index and time-kill curve was used to investigate the synergistic effect of silver nanoparticle combinations. The hemolytic activity was determined using an erythrocyte hemolytic assay. Our results revealed that silver nanoparticles, Triclosan, and trans- cinnamaldehyde (TCA) inhibited S.aureus and E.coli biofilms. Silver nanoparticles with TCA showed a synergistic effect (FICI values 0.35 and 0.45 against S. aureus and E. coli biofilms, respectively), and silver nanoparticles with Triclosan showed complete inhibition of S. aureus biofilm. The hemolytic activity was <2.50% for the combinations. [ABSTRACT FROM AUTHOR]

The purpose of this study is to optimize the Green synthesis of AgNPs using various quantities (0.5, 0.75, 1, 1.25, 1.5, 1.75 ml) of Ruta leaf extracts, the biosynthesized AgNPs were characterized using several methods such as UV-Vis spectrum, FTIR spectroscopy, X-ray diffraction (XRD), FESEM, EDX analysis, DLS and zeta potential. The examination of the visible and ultraviolet spectra revealed an absorption peak in the region of 405–420 nm. Through the use of Fourier Transform Infrared (FTIR) spectroscopy, the functional groups that were found in the Ruta plant extract were analyzed in order to locate the components that were accountable for reducing the silver nitrate. Through XRD, which occurs in the form of (111) lattice planes in the face-centered cubic (FCC) structure of metallic silver, the biosynthesized AgNPs were a semispherical shape with a nanoscale size ranging between 30–50 nm and moderately stable at −22.53 mV and −25.88 mV. From the results of the tests, it was found from results that the optimum value for the extract volume is (1.5 ml) to show the optimal properties of silver nanoparticles. [ABSTRACT FROM AUTHOR]

Polyvinylidene fluoride (PVDF) membranes were coated with TiO2 and TiO2-Ag to enhance their efficiency for oil-in-water emulsion separation. The photocatalytic activities of the two modified membranes and their filtration performances were compared in detail. The significantly enhanced photocatalytic activity of the TiO2-Ag composite was proved using a methyl orange (MO) solution (c = 10−5 M) and a crude oil emulsion (c = 50 mg·L−1). The TiO2-Ag-coated membrane reduced the MO concentration by 87%, whereas the TiO2-modified membrane reached only a 46% decomposition. The photocatalytic reduction in the chemical oxygen demand of the emulsion was also ~50% higher using the TiO2-Ag-coated membrane compared to that of the TiO2-coated membrane. The photoluminescence measurements demonstrated a reduced electron/hole recombination, achieved by the Ag nanoparticle addition (TiO2-Ag), which also explained the enhanced photocatalytic activity. A significant improvement in the oil separation performance with the TiO2-Ag-coated membrane was also demonstrated: a substantial increase in the flux and flux recovery ratio (up to 92.4%) was achieved, together with a notable reduction in the flux decay ratio and the irreversible filtration resistance. Furthermore, the purification efficiency was also enhanced (achieving 98.5% and 99.9% COD and turbidity reductions, respectively). Contact angle, zeta potential, scanning electron microscopy (SEM), and atomic force microscopy (AFM) measurements were carried out to explain the results. SEM and AFM images revealed that on the TiO2-Ag-coated membrane, a less aggregated, more continuous, homogeneous, and smoother nanolayer was formed due to the ~50% more negative zeta potential of the TiO2-Ag nanocomposite compared to that of the TiO2. In summary, via Ag addition, a sufficiently hydrophilic, beneficially negatively charged, and homogeneous TiO2-Ag-coated PVDF membrane surface was achieved, which resulted in the presented advantageous filtration properties beyond the photocatalytic activity enhancement. [ABSTRACT FROM AUTHOR]

For the first time in this study, silver nanoparticles (AgNPs) and gold nanoparticles (AuNPs) were green synthesized by the cost-effective and eco-friendly procedure using Cotton seed meal and Fodder yeast extracts. The biosynthesized NPs were characterized by UV–Vis spectroscopy, dynamic light scattering analysis (DLS), transmission electron microscopy (TEM), selected area electron diffraction (SAED), and fourier-transform infrared (FTIR) spectroscopy. Furthermore, the biosynthesized NPs were tested in vitro against biofilm formation by some pathogenic negative bacteria (Escherichia coli, Proteus mirabilis, Klebsiella sp., Salmonella sp., and Pseudomonas aeruginosa) and negative bacteria (staphylococcus aureus) as well as against human denovirus serotype 5 (HAdV-5) and anticancer activity using HepG2 hepatocarcinoma cells. UV–Vis absorption spectra of reaction mixture of AgNPs and AuNPs exhibited maximum absorbance at 440 nm and 540 nm, respectively. This finding was confirmed by DLS measurements that the highest intensity of the AgNPs and AuNPs were 84 nm and 73.9 nm, respectively. FTIR measurements identified some functional groups detected in Cotton seed meal and Fodder yeast extracts that could be responsible for reduction of silver and gold ions to metallic silver and gold. The morphologies and particle size of AgNPs and AuNPs were confirmed by the TEM and SAED pattern analysis. Biosynthesized AgNPs and AuNPs showed good inhibitory effects against biofilms produced by Escherichia coli, Proteus mirabilis, Klebsiella sp., Salmonella sp., Pseudomonas aeruginosa, and Staphylococcus aureus. In addition, they showed anticancer activities against hepatocellular carcinoma (HepG-2) and antiviral activity against human adenovirus serotype 5 infection in vitro. Finally, the results of this study is expected to be extremely helpful to nano-biotechnology, pharmaceutical, and food packing applications through developing antimicrobial and/or an anticancer drugs from ecofriendly and inexpensive nanoparticles with multi-potentiality. [ABSTRACT FROM AUTHOR]

Introduction: Nanotechnology is promising for the development of new effective medicines. Silver nanoparticle preparations have been particularly well studied and a range of beneficial effects have been identified. Despite this, the sale of Colloidal silver (CS) preparations for therapeutic purposes has been banned by multiple regulatory authorities (including the FDA and TGA) on the basis of their perceived toxicity. This study evaluates the toxicity of electrolytically produced (CS) preparation, as well as some compounds used to produce CS by chemical synthesis. Materials and Methods: Toxicity of the CS preparation and the chemical toxins were evaluated using the Artemia nauplii toxicity assay. Additionally, the CS was tested for its protective effects against citrate and tannic acid-induced toxicity by screening combinations of CS and the toxins. Results: The CS preparation was nontoxic in the Artemia nauplii bioassay at all concentrations tested and did not induce mortality substantially above the seawater control at all concentrations ≤50 μg/mL. In contrast, citrate and tannic acid were strongly toxic, with LC50 values of 11.6 and 26.8 μg/mL respectively. Interestingly, co-incubation of varying concentrations of the CS preparation with 30 μg/mL of citrate resulted in protection against toxicity, with 50 μg/mL CS inhibiting ~65% of citrate-induced toxicity. In contrast, the CS preparation had no apparent effects on tannic acid-induced toxicity. Conclusion: The CS preparation tested in our study was nontoxic at all concentrations tested. Furthermore, the CS mitigated the toxic effects of citrate, but had no apparent effect on tannic acid-induced toxicity. Further studies are required to verify these findings in other toxicity models and to study the protective molecular mechanisms. [ABSTRACT FROM AUTHOR]

Topical anticaries agents are non‐invasive methods to control and prevent dental caries. SDF is a fluoride‐based agent added to the arsenal of caries prevention tools. It has got a lot of attention since its introduction in the 1970s because of its ability to prevent and arrest caries, as well as its excellent antibacterial and anti‐plaque action. SDF reduces acid production by microorganisms, decreases the Streptococcus mutans count, biofilm formation, increases enamel resistance, and promotes dentinal tubule obliteration when applied to the dental surface. SDF also assists in the remineralization of dentin. A biannual application of 38% SDF has been effective at preventing dentin demineralization. This "silver bullet" can be seen as an alternative for caries prevention in special health care needs children which is minimally invasive and safe. Along with the advantages, there are some disadvantages, and work has been carried out to explore the use of silver nanoparticles (SNP) as anticaries agents to shield the teeth from aesthetic damage caused by Silver diamine fluoride. SNPs are identified to have the potential to prevent and inhibit dental caries while not discoloring demineralized dental enamel. SNPs have a greater surface area for interaction with microorganisms than other particles, making them more effective antimicrobial agents. Fluoride combined with SNP solution has a synergistic effect that promotes enamel remineralization while also acting as a bactericidal agent against cariogenic microorganisms. This review aims to bring out the various advantages and disadvantages related to the use of SDF and SNPs to aid in future research. [ABSTRACT FROM AUTHOR]

Polymer nanocomposite materials with catalytic activity were designed via modification of MF-4SK ion-exchange membranes with Au and Ag nanoparticles obtained according to various synthetic methods in reverse micellar solutions. A sufficient transparency of the films allowed us to detect nanoparticles in the films using UV–Vis spectrophotometry, monitoring changes in the content of metal nanoparticles in the reverse micellar solution. A different mechanism of interaction of Au and Ag nanoparticles obtained by the same synthetic method with the MF-4SK film upon their contact with its surface was discovered, the destruction of nanoparticles was observed, and the influence of mechanism of primary acts in the formation of metal nanoparticles in reverse micellar solutions on their adsorption properties was confirmed. The highest concentration of gold nanoparticles was found in films immersed in reverse micellar solutions at the time of their exposure to ionizing radiation. [ABSTRACT FROM AUTHOR]

Localized surface plasmon resonance from metallic nanoparticles (NPs) under optical excitation brings out intriguing applications in photonics. We realize plasmon-enhanced Raman scattering of two-dimensional (2D) materials (up to 19 times of magnitude for SnSe2 and 12 times for MoS2) via embedded silver nanoparticles in fused silica glass (hereby Ag NPs:glass), suggesting that the fabricated ion-modified multifunctional substrate shows a good compatibility that couple with 2D nanosheets. Moreover, the existence of insulating layers of SiO2 blocks the direct electron transfer and protects the intrinsic properties of surface materials, the Ag NPs:glass substrate exhibits excellent environmental stability and reusability, maintaining higher enhancement ability after a number of repeated uses. Our work opens up a novel route to develop reusable functional substrates for practical applications toward the weak-signal detection and label-free enhanced Raman scattering. [ABSTRACT FROM AUTHOR]

Graphitic carbon electrodes are central to many electrochemical energy storage and conversion technologies. Probing the behavior of molecular species at the electrochemical interfaces they form is paramount to understanding redox reaction mechanisms. Combining surface-enhanced Raman scattering (SERS) with electrochemical methods offers a powerful way to explore such mechanisms, but carbon itself is not a SERS activating substrate. Here, we report on a hybrid substrate consisting of single- or few-layer graphene sheets deposited over immobilized silver nanoparticles, which allows for simultaneous SERS and electrochemical investigation. To demonstrate the viability of our substrate, we adsorbed anthraquinone-2,6-disulfonate to graphene and studied its redox response simultaneously using SERS and cyclic voltammetry in acidic solutions. We identified spectral changes consistent with the reversible redox of the quinone/hydroquinone pair. The SERS intensities on bare silver and hybrid substrates were of the same order of magnitude, while no discernible signals were observed over bare graphene, confirming the SERS effect on adsorbed molecules. This work provides new prospects for exploring and understanding electrochemical processes in situ at graphitic carbon electrodes. [ABSTRACT FROM AUTHOR]

Give the emergence of drug resistance in bacteria resulting from antibiotic misuse, there is an urgent need for research and application of novel antibacterial approaches. In recent years, nanoparticles (NPs) have garnered significant attention due to their potential to disrupt bacteria cellular structure through loading drugs and special mechanisms, thus rendering them inactive. In this study, the surface of hollow polydopamine (HPDA) NPs was utilized for the growth of Prussian blue (PB), resulting in the formation of HPDA-PB NPs. Incorporation of Co element during the preparation process led to partial doping of PB with Co2+ ions. The performance test results demonstrated that the HPDA-PB NPs exhibited superior photothermal conversion efficiency and peroxidase-like activity compared to PB NPs. HPDA-PB NPs have the ability to catalyze the formation of hydroxyl radicals from H2O2 in a weakly acidic environment. Due to the tiny PB particles on the surface and the presence of Co2+ doping, they have strong broad-spectrum antibacterial properties. Both in vitro and in vivo evaluations confirm their efficacy against various bacterial strains, particularly Staphylococcus aureus, and their potential to promote wound healing, making them a promising candidate for advanced wound care and antimicrobial applications. [ABSTRACT FROM AUTHOR]

Yttrium oxide (Y2O3) is a promising rare-earth compound that is rarely studied. This study reports on the synthesis, structural, morphological, optical and antimicrobial properties of Y2O3 nanoparticles (NPs) synthesized using Agathosma betulina leaf extract. XRD pattern indicated that the crystalline phase was achieved for the sample calcined at 5 0 0 ∘ C with body-centered cubic symmetry. SEM and TEM images of Y2O3 nanopowder showed the nearly spherical morphology of agglomerated NPs with an average diameter of 13 nm. Optical properties revealed that the bandgap of Y2O3 NPs (∼ 5. 6 7 eV) has been increased compared with the bulk Y2O3 (∼ 5. 5 eV). Moreover, the antimicrobial activity was also evaluated against gram-positive and gram-negative bacteria of clinical interest. Results demonstrated that the synthesized Y2O3 NPs exhibited higher bacteriostatic effects against gram-negative bacterial strains due to their thin cell wall structure. These results show that the synthesized Y2O3 NPs are suitable for antibacterial control systems and medicines. [ABSTRACT FROM AUTHOR]

Silver nanoparticles (AgNPs) have extensive applications in nanomedicine and parasitology, particularly as antifungal, bactericidal, antiviral, larvicidal, mosquitocidal, and tick-killing agents. Plant-based AgNPs (PB-AgNPs) have been studied as a safer and biocompatible strategy to collaborate in disease control. However, knowledge concerning the toxicity of PB-AgNPs in non-target organisms is still limited. A scientometric and systematic review was conducted to comprehensively understand the potential toxicity associated with these nanoparticles. In brief, the assessment of PB-AgNPs toxicological and ecotoxicity aspects needs to be aligned with their development for target organisms. Our review demonstrates that different PB-AgNPs can cause lethal and sublethal effects like increased oxidative stress, cardiotoxicity, neurotoxicity, hepatotoxicity, hematotoxicity, and, DNA damage, alongside others, particularly in aquatic organisms. Besides, the toxicity of PB-AgNPs for terrestrial and some aquatic organisms remains poorly understood. Additionally, the similar LC50 range between non-target aquatic organisms and target organisms highlights the potential ecological impact of PB-AgNPs. Comprehensive toxicological assessments and further research are crucial to ensure the safe and sustainable use of PB-AgNPs in a One Health context. [ABSTRACT FROM AUTHOR]

[Display omitted] Plasmon-mediated chemical reaction (PMCR) is a highly attractive field of research. Here we report in situ surface-enhanced Raman spectroscopic (SERS) monitoring of plasmonic-mediated S S bond-forming reaction. The reaction is thought to be a self-coupling reaction proceeding by photoinduced aromatic S C bond arylation. Surprisingly, the S C arylation and S S coupling are found to be occurred on both partially oxidized silver and silver nanoparticles. The results demonstrated that silver oxide or hydroxide and small molecule donor sacrifice agent played a crucial role in the reaction. This work facilitates the in-situ manipulation and characterization of the active silver electrode interface in conjunction with electrochemistry, and also establishes a promising new guideline for surface plasmon resonance photocatalytic reactions on metal nanostructures with high efficiency. [ABSTRACT FROM AUTHOR]

The detection and quantification of pharmaceutical compounds in various matrices, including environmental and biological samples, has received a great deal of attention due to their potential impact on human health and the environment. In this study, we present an electrochemical approach for the determination of nimesulide, a commonly used non-steroidal anti-inflammatory drug, in water supply, synthetic urine and drug samples. A 3D-printed electrochemical sensor was fabricated and modified by an electrochemical treatment in alkaline medium with KOH, followed by the electrodeposition of silver nanoparticles to improve its detection capabilities. The performance of the electrochemical sensor was evaluated by multiple techniques and a flow injection analysis with amperometric detection was applied for the quantification of nimesulide. The FIA-AMP system allowed for the efficient introduction of samples, promoting rapid analysis and minimizing memory effects. The sensor connected to the method showed good sensitivity (0.171 ± 0.002 µA L mol−1 cm−2) and improved stability (RSD < 7%) and its electrochemical responses were correlated with the concentration of nimesulide present in the samples tested, with recovery values in the 92 to 104% range. The method developed showed a good linear range from 5 to 25 µmol L−1 and a low detection limit of 0.81 µmol L−1, which makes it suitable for the quantitative analysis of nimesulide over a range of concentrations. The sensor applied to the determination of nimesulide offers a promising platform for the sensitive and selective detection of pharmaceutical compounds, contributing to greater safety and sustainability in these fields. [ABSTRACT FROM AUTHOR]