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Advancement of reliable and eco-friendly approaches for nanoparticles growth is a basic key to the regulation of nanotechnology. For a decade, various nanoparticles have been constantly evaluated and used for different applications. In particular, bismuth (Bi) nanoparticles are receiving great interest due to different properties such as the low band gap (which lies in the UV region) and non-toxicity as compared to other metal nanoparticles. Use of poisonous chemicals or physical and chemical methods has been increased; therefore, the green approach has been plants, bacteria, viruses, fungi and other biomolecules preferred for the synthesis of bismuth nanoparticles. This review is focused on the green synthesis rather than chemical synthesis of Bi nanoparticles and their numerous applications including biological (antimicrobial), biomedical (imagining, Drug delivery photothermal therapy and cancer therapy), photocatalytic and hydrogen storage. As review articles often serve as key references for newcomers to the field, this report directs readers to articles showcasing significant advancements in Bi-based nanoparticle research. The objectives of this study include highlighting the non-toxic properties of Bi nanoparticles as effective antimicrobial agents and potential alternatives to antibiotics, outlining the limitations of green synthesis and in-vitro and in-vivo synthesis for Bi-based nanoparticles, comparing the efficiency of Bi-based nanoparticles with other types in various applications, and providing recommendations for future research endeavours. [ABSTRACT FROM AUTHOR]

Three phases (α, β, and γ) of manganese dioxide (MnO2) are successfully stabilized in a single entity for the first time. For this purpose, Citrullus colocynthis (bitter apple) extract is used as a natural surfactant in green synthesis. MnO2 nanoparticles were synthesized in the presence and absence of plant extracts under the same conditions. The morphology of both products is analysed by SEM and STEM to understand the role of plant extract in controlling the morphology of particles. The crystallinity and composition are analysed by XRD and confirmed that the product is composed of multiple phases α, β, and γ. The reduction of dyes and nitroarenes is studied using MnO2 nanoparticles (green and chemical products) as catalysts. The apparent rate constant, a percentage reduction, time reduction and reduced concentration compare the activities of both catalysts. After comparative data analysis, the catalytic reduction of picric acid is found fastest among all the substrates. All the results are analysed based on structure, functional group and affinity towards catalysts. [ABSTRACT FROM AUTHOR]

Polymicrobial mastitis is now becoming very common in dairy animals, resulting in exaggerated resistance to multiple antibiotics. The current study was executed to find drug responses in individual and mixed Culture of Staphylococcus aureus and Escherichia coli isolated from milk samples, as well as to evaluate the antibacterial potential of tungsten oxide nanoparticles. These isolates (alone and in mixed culture) were further processed for their responses to antibiotics using the disc diffusion method. On the other hand, tungsten oxide WO3 (W) nanoparticles coupled with antibiotics (ampicillin, A, and oxytetracycline, O) were prepared through the chemical method and characterized by X-ray diffraction, scanning electron microscopy (SEM), and UV-visible techniques. The preparations consisting of nanoparticles alone (W) and coupled with ampicillin (WA) and oxytetracycline (WO) were tested against individual and mixed Culture through the well diffusion and broth microdilution methods. The findings of the current study showed the highest resistance in E. coli was against penicillin (60%) and ampicillin (50%), while amikacin, erythromycin, ciprofloxacin, and oxytetracycline were the most effective antibiotics. S. aureus showed the highest resistance against penicillin (50%), oxytetracycline (40%), and ciprofloxacin (40%), while, except for ampicillin, the sensitive strains of S. aureus were in the range of 40–60% against the rest of antibiotics. The highest zones of inhibition (ZOI) against mixed Culture were shown by imipenem and ampicillin, whereas the highest percentage decrease in ZOI was noted in cases of ciprofloxacin (−240%) and gentamicin (−119.4%) in comparison to individual Culture of S. aureus and E. coli. It was noteworthy that the increase in ZOI was not more than 38% against mixed Culture as compared to the individual Culture. On the other hand, there was a significant reduction in the minimum inhibitory concentration (MIC) of nanoparticle-coupled antibiotics compared to nanoparticles alone for individual and mixed-culture bacteria, while MICs in the case of mixed Culture remained consistently high throughout the trial. This study therefore concluded that diverse drug resistance was present in both individual and mixed-culture bacteria, whereas the application of tungsten oxide nanoparticle-coupled antibiotics proved to be an effective candidate in reversing the drug resistance in bacterial strains. [ABSTRACT FROM AUTHOR]

The rise in prevalence and drug resistance in Staphylococcus aureus of dairy animals require an alternative to antibiotics. Nanoparticles particularly metallic nanoparticles are a wise approach to modulating drug resistance. The current study thus focuses on the replacement of antibiotics with ZnO, MgO, and Fe2O3 nanoparticles. To achieve this goal, 200 cattle milk samples were collected aseptically and screened for subclinical mastitis using the purposive sampling technique. Following Bergey's manual of determinative bacteriology, S.aureus was identified and antibiotic susceptibility was tested using clinical laboratory and standard institute guidelines. On the other hand, resistant strains were put to antibacterial testing assay against metallic nanoparticles both by well diffusion and broth microdilution method. To analyze the data, both probability and non-probability statistical tools were applied using SPSS version 22 of statistical software at 5% probability. The current study showed 24.56% of S. aureus positive from commercial dairy while the resistance of these isolates against gentamicin, enrofloxacin, levofloxacin, and vancomycin was found to be 50, 40, 30, 30%, respectively. On the other hand, a disc diffusion assay was concluded with 24.525±0.806 mm (ZnO) followed by 16.475±0.950mm (MgO) and 13.150±1.392mm (Fe2O3). MgO stood first to contribute lowest Minimum inhibitory concentration (MIC) (1.302±0.564 mg/mL) followed by Fe2O3 (2.930±1.691 mg/mL) and ZnO (3.906±0.000 mg/mL). MIC of ZnO was recorded to be 18.23±11.93 mg/mL, 15.63±0.0 mg/mL, 13.02±4.5 mg/mL, 7.81±6.77 mg/mL, 5.21±2.26 mg/mL, and (3.906±0.000 mg/mL) at 04, 08, 12, 16, 20 and 24th h of incubation. A similar trend was followed by other nanoparticles at different hours of incubation. The study thus concludes a rise in resistant strains of S. aureus in bovine milk while metallic nanoparticles as effective alternatives. [ABSTRACT FROM AUTHOR]

Alternative and modified therapeutic approaches are key elements in culminating antibiotic resistance. To this end, an experimental trial was conducted to determine the cytotoxicity and antibacterial potential of composites of magnesium oxide (MgO) nanoparticles and antibiotics stabilized in sodium alginate gel against multi-drug-resistant Staphylococcus aureus isolated from a houbara bustard. The characterization of preparations was carried out using X-ray diffraction (XRD), scanning transmissible electron microscopy (STEM), and Fourier-transform infrared spectroscopy (FTIR). The preparations used in this trial consisted of gel-stabilized MgO nanoparticles (MG), gel-stabilized tylosin (GT), gel-stabilized ampicillin (GA), gel-stabilized cefoxitin (GC), gel-stabilized MgO and tylosin (GMT), gel-stabilized MgO and cefoxitin (GMC), and gel-stabilized MgO and ampicillin (GMA). The study presents composites that cause a lesser extent of damage to DNA while significantly enhancing mitotic indices/phases compared to the other single component preparations with respect to the positive control (methyl methanesulphonate). It was also noted that there was a non-significant difference (p > 0.05) between the concentrations of composites and the negative control in the toxicity trial. Studying in parallel trials showed an increased prevalence, potential risk factors, and antibiotic resistance in S. aureus. The composites in a well diffusion trial showed the highest percentage increase in the zone of inhibition in the case of GT (58.42%), followed by GMT (46.15%), GC (40.65%), GMC (40%), GMA (28.72%), and GA (21.75%) compared to the antibiotics alone. A broth microdilution assay showed the lowest minimum inhibitory concentration (MIC) in the case of GMA (9.766 ± 00 µg/mL), followed by that of GT (13.02 ± 5.64 µg/mL), GMC (19.53 ± 0.00 µg/mL), GA (26.04 ± 11.28 µg/mL), GMT (26.04 ± 11.28 µg/mL), MG (39.06 ± 0.00 µg/mL), and GC (39.06 ± 0.00 µg/mL). The study thus concludes the effective tackling of multiple-drug-resistant S. aureus with sodium-alginate-stabilized MgO nanoparticles and antibiotics, whereas toxicity proved to be negligible for these composites. [ABSTRACT FROM AUTHOR]

In present research, novel cobalt bismuth layered double hydroxides (Co/Bi‐LDHs) were fabricated by urea hydrolysis approach at laboratory scale in mixed solvent of water and ethylene glycol. Synthesized product was analyzed by different techniques such as powder X‐ray diffraction (PXRD), scanning electron microscopy (SEM), and Fourier transmission infrared spectroscopy (FTIR). Cobalt oxide (Co3O4) was obtained after calcinations in nanometer range, which showed excellent catalytic characteristics. Calcined LDHs were used as photocatalyst to degrade Congo Red (CR) under different conditions of catalyst and hydrogen peroxide. Different parameters such as flash point, fire point, cloud point, pour point, kinematic viscosity, and specific gravity were also studied in order to check the efficiency of commercial diesel at different concentrations of catalyst. [ABSTRACT FROM AUTHOR]

Rhipicephalus ticks are described as important ticks impacting the costs of livestock rearing and by-products sale. The prevalence and response of ticks towards cypermethrin sprays indicate the need to implement the rational use of acaricides. In our previous studies, ZnO nanoparticles were shown to inhibit the major life-cycle stages of Hyalomma ticks, indicative of promising application of nanomaterials against the hard ticks. The current study was designed to probe into one of alternative options to curtail Rhipicephalus ticks by employing cypermethrin-coated nanoparticles of ZnO (C-ZnO NPs) and ZnS (C-ZnS NPs). The nanocomposites showed a roughly spherical type of morphology and various size dimensions upon characterization using SEM and EDX. Female ovipositioning was declined up to only 48% in ZnS and up to 32% in ZnO NPs even after 28 days in vitro. Similarly, the larval hatching was also impacted, leading to a hatching percentage of 21% and 15% by application of C-ZnS NPs and C-ZnO NPs, respectively. The LC90 in female adult groups were 3.94 mg/L and 4.27 mg/L for the C-ZnO NPs and C-ZnS NPs groups, respectively. Similarly, the larval groups had LC90 of 8.63 and 8.95 mg/L for the C-ZnO NPs and C-ZnS NPs groups. The study is a proof of the concept for incorporating effective and safe nanocomposites as acaricides. The studies on the efficacy and spectrum of non-target effects of nanomaterial-based acaricides can further refine the research on finding novel alternatives for tick control. [ABSTRACT FROM AUTHOR]

Nanocomposites become very important because of their reduce size (1–100 nm), large surface area, excellent optical magnetic, and electrical and mechanical properties. In many applications, graphene oxide‐based metallic nanocomposites emerged as an outstanding class of nanomaterials that are used for different applications. (GO‐ZnO) nanocomposite has gained more importance in recent years. The present research study is designed to synthesize nanocomposites and aims to monitor its characteristics and applications. Graphene oxide is synthesized by Hummers' method. Metal salts are used as precursor source of respective metal oxides. Wet chemical synthesis method such as solvothermal/hydrothermal and copreciptation processes is used because of its low cost and easy applications as compared with other processes used in the past, which have been costly and difficult to handle. Scanning electron microscopy (SEM) and X‐ray diffraction (XRD) techniques are used to discriminate GO‐Zinc oxide metallic nanocomposites. XRD is used to investigate the crystal structure, and SEM images showed that the synthesized GO/ZnO nanocomposites is irregular in shape with merged surfaces and the size is 100 nm−1 μm. The dark and light color shows hollow morphology of the nanocomposites, and particles are merged with each other and irregular in shape. The obtained data are statistically analyzed by using regression analysis for the further interpretations. VESTA, MATCH, Origin pro is used for the interpretation of XRD results of synthesized nanocomposites. Applications of metallic (GO/Zn) nanocomposite as catalytic activity and colorimetry, flash point, fire point, cloud point, pour point, specific gravity, and viscosity and for the degradation of Drimarene Red K‐4BL is performed. [ABSTRACT FROM AUTHOR]

Poly (N-isopropylacrylamide-acrylic acid) [p(NIPAM-AAc)] microgel was successfully fabricated using the precipitation polymerization method. Silver (Ag) nanoparticles and graphene oxide (G) were used to fabricate the following hybrid microgels: Ag-p(NIPAM-AAc) (Ag-HMG), Ag-G-p(NIPAM-AAc) (Ag-G-HMG), and G-p(NIPAM-AAc) (G-HMG). Ag-HMG, Ag-G-HMG, and G-HMG were characterized using a Zetasizer and UV-Vis spectroscopy. The reduction of a series of different compounds with comparable and distinct chemical structures was catalyzed by synthesized Ag-HMG, Ag-G-HMG, and G-HMG hybrid microgels. The average size of Ag nanoparticles was found to be ~50 nm. Ag nanoparticles were synthesized within microgels attached to G sheets. Ag-p(NIPAM-AAc), Ag-G-p(NIPAM-AAc), and G-p(NIPAM-AAc) hybrid microgels were used for the catalytic reduction of nitroarenes and dyes. By comparing their apparent rate constant (kapp), reduction duration, and percentage reduction, the activity of HMG (hybrid microgel) as a catalyst towards different substrates was investigated. Graphene sheets play role in electron relay among Ag nanoparticles and microgels. [ABSTRACT FROM AUTHOR]

Responsive molecularly imprinted microgels (MIGs) have gained a lot of interest due to their responsive specificity and selectivity for target compounds. Study on MIGs is rapidly increasing due to their quick responsive behavior in various stimuli like pH and temperature. MIGs show unique property of morphology control on in-situ synthesis of nanoparticles in response of variation in reactant concentration. Literature related to synthesis, parameters, characterization, applications and prospects of MIGs are critically reviewed here. Range of templates, monomers, initiators and crosslinkers are summarized for designing of desired MIGs. This review article describes effect of variation in reactants combination and composition on morphology, imprinting factor and percentage yield of MIGs. Hydrolysis of similar templates using MIGs is also described. Relation between percentage hydrolysis and hydrolysis time of targets at different temperatures and template:monomer ratio is also analyzed. Possible imprinting modes of ionic/non-ionic templates and its series are also generalized on the basis of previous literature. MIGs are investigated as efficient anchoring vehicles for adsorption, catalysis, bio-sensing, drug delivery, inhibition and detection. [ABSTRACT FROM AUTHOR]

Ticks (Acari: Ixodidae) are blood-feeding parasites capable of transmitting diseases to animals (Piroplasmosis) and humans (Congo fever, Lyme disease). The non-judicious use of chemical acaricides has led to the development of acaricide-resistant ticks, making the control of ticks and tick-borne diseases difficult. This study reports the efficacy of magnesium oxide (MgO), iron oxide (Fe2O3), and zinc oxide (ZnO) nanoparticles (NPs) as alternatives to traditional acaricides/pesticides using in vitro tests against major representative stages of Hyalomma ticks. Nanopesticides were chemically synthesized as rods (Fe2O3), stars (ZnO), and spheres (MgO) and were characterized by XRD and SEM analysis. The in vitro bioassays included adult immersion, larval immersion, and larval packet tests. Non-target effects of the nanopesticides were evaluated using snails. The LC90 values of Fe2O3 NPs (4.21, 2.83, 0.89 mg/L) were lowest followed by MgO (4.27, 2.91, 0.93 mg/L) and ZnO (4.49, 3.05, 0.69 mg/L), for the tick adult, larval and egg stages, respectively. Fe2O3 NPs were capable of arresting oviposition and larval hatching in the study ticks in vitro. The snail toxicity experiments revealed minimum to mild off-target effects for all nanopesticides tested. This study is the first to report the comparative efficacy of magnesium, iron, and zinc nanomaterials for toxicity in egg, adult and larval stages of Hyalomma ticks. Further studies of NPs on establishing the efficacy against ticks and safety at host-human-environment interface could lead to promising nanopesticde applications. [ABSTRACT FROM AUTHOR]

Manganese–tin bimetallic oxide (MnSnO3) is synthesized by the solvothermal approach using manganese acetate and stannic chloride as precursors and urea as a precipitating agent in an aqueous medium. The crystallinity, purity and lattice parameters of the product are analysed by the X-ray diffraction analysis. The morphology of the product is analysed with the help of a scanning electron microscopy. The synthesized product is used as a fuel additive and catalyst. Synthesized MnSnO3 is used as a catalyst for the degradation of an organic dye Congo red in the aqueous medium. Catalytic degradation is monitored at different concentrations of the catalyst and hydrogen peroxide. Moreover, the role of MnSnO3, as an additive in diesel fuel, is studied. The efficiency of the modified fuel is analysed by studying the different parameters such as flash point, fire point, cloud point, pour point, calorific values and specific gravity. The values of these parameters change significantly by changing the dosage of the additive. [ABSTRACT FROM AUTHOR]