Journal of Nanotechnology最新文献

{"title":"Anticancer and Antimicrobial Activity Evaluation of Cowpea-Porous-Starch-Formulated Silver Nanoparticles","authors":"Shiara Ramdath, J. Mellem, L. Mbatha","doi":"10.1155/2021/5525690","DOIUrl":"https://doi.org/10.1155/2021/5525690","url":null,"abstract":"Health issues involving inadequate treatment of diseases such as cancer and microbial infections continue to be the subject of much ongoing recent research. Biosynthesized silver nanoparticles (AgNPs) were characterized using Transmission Electron Microscopy (TEM), Zeta Sizer, Ultraviolet (UV), and Fourier Transform Infrared (FTIR) spectroscopy. Their antimicrobial activity was evaluated on selected Gram-positive and Gram-negative bacterial strains, using the disc diffusion and broth dilution assays. Cell viability profiles were evaluated using MTT (3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide) and apoptosis studies on selected human noncancer and cancer cells. The biosynthesized AgNPs were evaluated to be spherical clusters, with sizes between 40 and 70 nm. The absorption peak at 423 nm and the presence of polyphenols confirmed the synthesis and stabilization of these tested AgNPs. The AgNPs showed a good stability of −23.9 ± 1.02 mV. Good antimicrobial activity (6.0–18.0 mm) was seen on all tested bacteria at a minimum inhibitory concentration (MIC) ranging from 5 to 16 μg/ml, with the highest activity seen against Gram-negative Escherichia coli (18 ± 0.5 mm), and the lowest activity was seen against Gram-positive Listeria monocytogenes (6.0 ± 0.4 mm) after treatment with the AgNPs. These NPs showed a concentration-dependent and cell-specific cytotoxicity with low IC50 values (41.7, 56.3, and 63.8 μg/ml). The NPs were well tolerated by tested cells as indicated by a more than 50% cell viability at the high dose tested and low apoptotic indices (<0.2). These findings indicated that these biosynthesized AgNPs showed great potential as effective antibacterial agents and anticancer drug delivery modalities.","PeriodicalId":16378,"journal":{"name":"Journal of Nanotechnology","volume":null,"pages":null},"PeriodicalIF":4.2,"publicationDate":"2021-05-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"82861813","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Microwave-Assisted Synthesis of CuO Nanoparticles Using Cordia africana Lam. Leaf Extract for 4-Nitrophenol Reduction","authors":"Aklilu Guale Bekru, Osman Ahmed Zelekew, D. Andoshe, F. K. Sabir, R. Eswaramoorthy","doi":"10.1155/2021/5581621","DOIUrl":"https://doi.org/10.1155/2021/5581621","url":null,"abstract":"Copper-oxide-based nanomaterials play an important role as a low-cost alternative to nanoparticles of precious metals for the catalytic reduction of 4-nitrophenols. In this study, CuO nanoparticles were synthesized by a microwave-assisted method using Cordia africana Lam. leaf extract for reduction or stabilization processes. The synthesized CuO nanoparticles (NPs) were characterized using X-ray diffraction analysis (XRD), Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM), and energy-dispersive spectroscopy (EDS). The analysis indicated that nanocrystals of the monoclinic CuO phase having a cluster of agglomerated morphology with a crystallite size of about 9 nm were synthesized. We also evaluated the catalytic performance of CuO NPs against 4-nitrophenol (4-NP) reduction. The catalyst has shown excellent performance completing the reaction within 12 min. Furthermore, the performance of CuO NPs synthesized at different pH values was investigated, and results indicated that the one synthesized at pH 7 reduced 4-NP effectively in shorter minutes compared to those obtained at higher pH values. The CuO NPs synthesized using Cordia africana Lam. leaf extract exhibited a better reducing capacity with an activity parameter constant of 75.8 min−1·g−1. Thus, CuO synthesized using Cordia africana Lam. holds a potential application for the catalytic conversion of nitroarene compounds into aminoarene.","PeriodicalId":16378,"journal":{"name":"Journal of Nanotechnology","volume":null,"pages":null},"PeriodicalIF":4.2,"publicationDate":"2021-03-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"73144402","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Antimicrobial Activity of the Synthesized of Copper Chalcogenide Nanoparticles","authors":"N. G. Mbewana-Ntshanka, M. Moloto, P. K. Mubiayi","doi":"10.1155/2021/6675145","DOIUrl":"https://doi.org/10.1155/2021/6675145","url":null,"abstract":"Antimicrobial activity of copper chalcogenides nanoparticles was investigated by synthesizing copper selenide, copper sulfide, and copper oxide via the hot-injection method. Since reaction time has a profound effect on the nanocrystals size and shapes, the effect of reaction time was also investigated during the synthesis of the copper chalcogenides to obtain nanocrystals with desired properties. The reaction time showed no effect on the phase composition of the synthesized copper sulfide, copper oxide, and copper selenide nanoparticles. However, the size variation of nanoparticles with different reaction time was observed. Reaction time of 30 minutes gave the best optical (the shape of the absorption band edge and emission maxima values) and structural (size distribution of particles) properties for CuSe and CuS compared to other reaction times (15, 45, and 60 min). Their band edges were located at 506 (2.45 eV) and 538 nm (2.30 eV), respectively. For this reaction time, copper selenide produced nanoparticles with a size range of 1–27 nm and copper sulfide nanoparticles ranged 1–18 nm. The morphologies of both chalcogenides at 30 min reaction time were spherical. Reaction time of 15 minutes gave the best optical and structural properties for copper oxide nanoparticles with a band edge of 454 nm (2.73 eV) and particle size ranging 0.8–3.2 nm, but nonetheless, 30 min was used as the optimum reaction time for all three chalcogenides. The optimum parameter (220°C, 30 min, and 1 : 1 ratio) was used to synthesize the three copper chalcogenides which were then tested against Gram-negative (E. coli and P. aeruginosa), Gram-positive (S. aureus and E. faecalis), and fungi (C. albicans) employing both agar disk diffusion and minimum inhibitory concentration (MICs) methods. Copper oxide nanoparticles showed more sensitivity towards four bacterial microorganisms than the other two chalcogenides followed by copper sulfide nanoparticles with copper selenide nanoparticles being the least sensitive. The sensitivity of copper oxide nanoparticles is attributed to the smaller size of oxygen atom which strongly affects its reactivity and stability and hence very stable and highly reactive compared to sulfur and selenium.","PeriodicalId":16378,"journal":{"name":"Journal of Nanotechnology","volume":null,"pages":null},"PeriodicalIF":4.2,"publicationDate":"2021-03-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"77183910","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Plant-Mediated Biosynthesis and Photocatalysis Activities of Zinc Oxide Nanoparticles: A Prospect towards Dyes Mineralization","authors":"M. A. Fagier","doi":"10.1155/2021/6629180","DOIUrl":"https://doi.org/10.1155/2021/6629180","url":null,"abstract":"In recent years, nanoparticles synthesis by green synthesis has gained extensive attention as a facile, inexpensive, and environmentally friendly method compared with chemical and physical synthesis methods. This review covered the biosynthesis of zinc oxide nanoparticles (ZnO NPs), including the procedure and mechanism. Factors affecting the formation of ZnO NPs are discussed. The presence of active bioorganic molecules in plant extract played a vital role in the formation of ZnO NPs as a natural green medium in the metallic ion reduction processes. ZnO NPs exhibit attractive photocatalysis properties due to electrochemical stability, high electron mobility, and large surface area. In this review, the procedure and mechanism of the ZnO photocatalysis process are studied. The effects of dyes amount, catalysts, and light on photodegradation efficiency are also considered. This review provides useful information for researchers who are dealing with green synthesis of ZnO NPs. Moreover, it can provide investigators with different perceptions towards the efficiency of biosynthesized ZnO NPs on dyes degradation and its restrictions.","PeriodicalId":16378,"journal":{"name":"Journal of Nanotechnology","volume":null,"pages":null},"PeriodicalIF":4.2,"publicationDate":"2021-03-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"85972972","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Adsorption of lead and iron present in the waters of the Santa River using titanium dioxide nanoparticles (TiO2) [Adsorción de plomo y hierro presentes en aguas del río Santa utilizando nanopartículas de dióxido de titanio (TiO2)]","authors":"Lenin Inquil Ayquipa, Jhonny Valverde Flores","doi":"10.32829/nanoj.v4i2.199","DOIUrl":"https://doi.org/10.32829/nanoj.v4i2.199","url":null,"abstract":"The objective of the investigation was to determine adsorption of lead and iron in waters coming from the Santa River, Recuay jurisdiction, Ancash. Then the synthesis of titanium dioxide nanoparticles (TiO2) was carried out by means of ultrasound, and finally the adsorption of the metal ions present in these waters by means of the titanium dioxide nanoparticles. The results indicate that the iron was adsorbed by 92.69% (from 31.86 mg/L to 2.33 mg/L) and the lead was adsorbed by 79.58% (from 2.361 mg/L to 0.482 mg/L) using 600mg of titanium dioxide nanoparticles (TiO2) and a treatment time of 60 minutes of treatment.","PeriodicalId":16378,"journal":{"name":"Journal of Nanotechnology","volume":null,"pages":null},"PeriodicalIF":4.2,"publicationDate":"2020-12-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"73627494","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Shear Thickening Fluids Comparative Analysis Composed of Silica Nanoparticles in Polyethylene Glycol and Starch in Water","authors":"R. Mankarious, M. Radwan","doi":"10.1155/2020/8839185","DOIUrl":"https://doi.org/10.1155/2020/8839185","url":null,"abstract":"Shear thickening fluid (STF) occurs in dispersions of highly condensed colloid particles and is categorized as a non-Newtonian fluid whose viscosity increases under shear loading which makes them beneficial in protective and impact resistance applications. The aim of this study is to synthesis two different STFs and characterize their microstructural properties to provide a data base for comparing the final macrobehavior of the two fluids under mechanical testing. Therefore, fumed silica and polyethylene glycol STF and starch with water STF-based dispersions were prepared. The particle size, zeta potential, SEM micrographs, and rheological analysis were performed for each type of STF. The effect of filler concentration was observed by using 10–30 weight% filling material. The rheological properties of STFs show higher viscosity measurements at same shear rates for starch/water STF than silica/PEG with maximum viscosity reaching 523.6 Pa s and 178.9 Pa s, respectively. Larger starch particle size over silica recorded as 303.7 nm and 16.49 nm, respectively, and zeta potential analysis recorded particle electrostatic charges as 22.6 mV and 12.8 mV, respectively, leading to more dispersion stability and obvious thickening effect at higher particle concentration leading to greater jump in viscosity at sudden shear rate. The results indicate the capability of trying more protective applications with more flexibility and less thickness when STF is implemented and a good database for the fluids to choose from according to their behavior.","PeriodicalId":16378,"journal":{"name":"Journal of Nanotechnology","volume":null,"pages":null},"PeriodicalIF":4.2,"publicationDate":"2020-12-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"85880652","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Corrigendum to “Antibacterial Screening of Gunnera perpensa-Mediated Silver Nanoparticles”","authors":"N. Patel, K. Kasumbwe, V. Mohanlall, L. Mbatha","doi":"10.1155/2020/7916862","DOIUrl":"https://doi.org/10.1155/2020/7916862","url":null,"abstract":"<jats:p />","PeriodicalId":16378,"journal":{"name":"Journal of Nanotechnology","volume":null,"pages":null},"PeriodicalIF":4.2,"publicationDate":"2020-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"75566899","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Fungus- (Alternaria sp.) Mediated Silver Nanoparticles Synthesis, Characterization, and Screening of Antifungal Activity against Some Phytopathogens","authors":"T. Win, Sikandar Khan, Pengcheng Fu","doi":"10.1155/2020/8828878","DOIUrl":"https://doi.org/10.1155/2020/8828878","url":null,"abstract":"The scientific consensus is now on developing a biocontrol agent that can cause cellular metabolic reprogramming against agricultural pathogens. Biosynthesis of silver nanoparticles was performed by using phytopathogenic fungi (Alternaria sp.) isolated from banana cultivated soil. Alternaria sp. can grow very fast and produce high enough bioactive compounds. This study aims to biosynthesize silver nanoparticles (AgNPs) using fungal Alternaria sp.’s metabolites as a safe antifungal agent against plant pathogenic fungi (Fusarium spp. and Alternaria sp.). To visualize the formation of AgNPs, analytical instruments were used, such as ultraviolet-visible (UV-Vis) spectroscopy, Fourier-transform infrared (FTIR) spectroscopy, scanning transmission electron microscopy (STEM), energy dispersive X-ray (EDX), and elemental mapping. The UV-visible spectra showed a peak at 435 nm. Analysis of scanning transmission electron microscopy (STEM) micrographs evidenced that the size of synthesized silver nanoparticles ranged between 3 and 10 nm. The resulting AgNPs showed distinct antifungal activity against selected plant pathogenic fungi. Synthesized AgNPs have demonstrated remarkable potential for the use of antifungal compounds to combat plant diseases.","PeriodicalId":16378,"journal":{"name":"Journal of Nanotechnology","volume":null,"pages":null},"PeriodicalIF":4.2,"publicationDate":"2020-11-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"74081445","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Synthesis of Copper Oxide Nanoparticles Using Plant Leaf Extract of Catha edulis and Its Antibacterial Activity","authors":"Worku Wubet Andualem, F. K. Sabir, E. T. Mohammed, H. Belay, B. Gonfa","doi":"10.1155/2020/2932434","DOIUrl":"https://doi.org/10.1155/2020/2932434","url":null,"abstract":"Development of green technology is generating interest of researchers towards ecofriendly and low-cost methods for biosynthesis of nanoparticles (NPs). In this study, copper oxide (CuO) NPs were synthesized using a copper nitrate trihydrate precursor and Catha edulis leaves extract as a reducing and capping agent during the synthesis. The biosynthesized CuO NPs were characterized using an X-ray diffractometer (XRD), scanning electron microscopy-energy-dispersive X-ray spectroscopy (SEM-EDS), transmission electron microscope (TEM), Ultraviolet visible spectroscopy (UV-Vis), and Fourier transform infrared (FTIR) spectroscopy. XRD characterization confirmed that the biosynthesized CuO NPs possessed a good crystalline nature which perfectly matched the monoclinic structure of bulk CuO. Furthermore, the results obtained from SEM and TEM showed that the biosynthesized CuO NPs were spherical in shape. EDS characterization of the biosynthesized NPs also indicated that the reaction product was composed of highly pure CuO NPs. Moreover, the antimicrobial activities of different concentrations of CuO NPs synthesized using Catha edulis extract were also tested. Accordingly, the result showed that the highest zone of inhibitions measured were for CuO NPs synthesized using 1 : 2 ratios at 40 mg/ml solution concentration and observed to be 22 ± 0.01 mm, 24 ± 0.02 mm, 32 ± 0.02 mm, and 29 ± 0.03 mm for S. aureus, S. pyogenes, E. coli, and K. pneumonia, respectively.","PeriodicalId":16378,"journal":{"name":"Journal of Nanotechnology","volume":null,"pages":null},"PeriodicalIF":4.2,"publicationDate":"2020-11-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"76893921","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Adsorption Behaviour and Kinetics of Zearalenone on Hydroxyl-Fe-Al-Intercalated Montmorillonite","authors":"Shengqiong Fang, Yu Xiao, Huiqiang Wang","doi":"10.1155/2020/7680738","DOIUrl":"https://doi.org/10.1155/2020/7680738","url":null,"abstract":"Pristine montmorillonite (Mont) was used as raw materials to prepare hydroxyl-Fe-pillared Mont, hydroxyl-Al-pillared Mont, and hydroxyl-Fe-Al-pillared Mont composites. By varying the OH/Fe and Fe/Al molar ratios during the preparation of the pillared Mont, the adsorption capacity of zearalenone (ZEA) and the kinetics were elucidated. The characterization of X-ray diffraction (XRD) and Fourier transform infrared (FT-IR) spectroscopy reveals the adsorption mechanism of pristine and modified Mont. The results indicated that the ZEA adsorption capacity is Mont (0.05 mg/g) << 1.5OH/Fe-Mont (0.28 mg/g) << OH/Al-Mont (0.51 mg/g) < 0.5Fe/Al-Mont (0.56 mg/g) in the condition of pH = 8 and 37°C, in which both 0.5Fe/Al-Mont and OH/Al-Mont reached maximum adsorption capacity and 1.5OH/Fe-Mont attained 5 times the capacity of Mont. Adsorption isotherm studies revealed that Freundlich adsorption isotherms best represented the experimental data. The kinetic data for ZEA adsorption revealed that the Mont adsorption capacity for ZEA equilibrates in 1 hour and is best described using the pseudo-second-order rate equation. The XRD analysis indicated that the amplification of Fe-dominant pillared Mont interlayer spacing is the main reason for the observed increases in the adsorption capacity of ZEA, while Al-dominant pillared Mont has a relatively stable Keggin structure; therefore, interlayer spacing is not the primary mechanism for changes in the adsorption capacity of both OH/Al-Mont and Al-dominant pillared Mont. An FT-IR analysis demonstrated that cationic exchange was the dominant mechanism that allowed ZEA and hydroxyl-Al ions to enter the Mont interlayers, while this cationic exchange mechanism was not the dominant mechanism used by hydroxyl-Fe entering the Mont layers.","PeriodicalId":16378,"journal":{"name":"Journal of Nanotechnology","volume":null,"pages":null},"PeriodicalIF":4.2,"publicationDate":"2020-08-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"85893337","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}