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1.
Five plant leaf extracts (Pine, Persimmon, Ginkgo, Magnolia and Platanus) were used and compared for their extracellular synthesis of metallic silver nanoparticles. Stable silver nanoparticles were formed by treating aqueous solution of AgNO3 with the plant leaf extracts as reducing agent of Ag+ to Ag0. UV-visible spectroscopy was used to monitor the quantitative formation of silver nanoparticles. Magnolia leaf broth was the best reducing agent in terms of synthesis rate and conversion to silver nanoparticles. Only 11 min was required for more than 90% conversion at the reaction temperature of 95 °C using Magnolia leaf broth. The synthesized silver nanoparticles were characterized with inductively coupled plasma spectrometry (ICP), energy dispersive X-ray spectroscopy (EDS), scanning electron microscopy (SEM), transmission electron microscopy (TEM), and particle analyzer. The average particle size ranged from 15 to 500 nm. The particle size could be controlled by changing the reaction temperature, leaf broth concentration and AgNO3 concentration. This environmentally friendly method of biological silver nanoparticles production provides rates of synthesis faster or comparable to those of chemical methods and can potentially be used in various human contacting areas such as cosmetics, foods and medical applications.  相似文献   

2.
Functionalizing nanostructured carbon nanofibers (CNFs) with bimetallic phosphides enables the material to become an active electrode for multifunctional applications. A facile electrospinning technique is utilized for the first time to develop NiCoP nanoparticles encapsulated CNFs that are used as an energy storage system of supercapattery, and as an electrocatalyst for oxygen reduction, oxygen evolution, and hydrogen evolution reaction in KOH electrolyte. Evolving from the inclusion of bimetallic phosphide nanoparticles, the NiCoP/CNF electrode unveils superior‐specific capacitance (333 Fg?1 at 2 Ag?1) and rate capability (87%). The fabricated supercapattery device offers a voltage of 1.6 V that supplies a remarkable energy density (36 Wh kg?1) along with an improved power density (4000 W kg?1) and unwavering cyclic stability (25 000 cycles). Meanwhile, the NiCoP/CNF electrode has simultaneously performed well as a multifunctional electrocatalyst for oxygen reduction reaction at a half‐wave potential of 0.82 V versus reversible hydrogen electrode and can attain a current density of 10 mA cm?2 at a very low overpotential of 268 and 130 mV for the oxygen evolution reaction and hydrogen evolution reaction, respectively. Thus, the NiCoP/CNF with all its inimitable electrode properties has profoundly proved its proficiency at handling multifunctional challenges in terms of both storage and conversion.  相似文献   

3.
Indian herbal plant species Lantana indica, Adhatoda vasica, Pandanus furcatus, Tylophora indica and Centella asiatica, traditionally used in ethno medicines to treat common infections and various disorders, have been studied for their antimicrobial and antioxidant activity. The methanolic extracts of the plant leaves exhibited significant and dose-dependent antioxidant activities in DPPH radical scavenging, ferric ion reducing and phosphomolybdate assays. These leaf extracts showed antimicrobial activity against selected Gram +ve and Gram ?ve bacterial strains. A. vasica and L. indica extracts possessed maximum antioxidant and antimicrobial activity, respectively. The activities could be correlated to phenolics and flavonoid content of the leaf extracts which ranged from 30.25 to 91.98 mg GAE g?1 dw leaf extract and 2.67 to 96.45 mg RE g?1 dw leaf extract respectively. The aqueous extracts of plant leaves significantly protected the DNA damage against the oxidative damage caused by hydroxyl radicals.  相似文献   

4.
Gold nanoparticles with their excellent biocompatibility are extensively used in pharma and biological applications. Terminalia bellerica (TB) dry fruit parts mediated gold nanoparticles were synthesized using the aqueous extracts. The secondary metabolites screening of the aqueous extracts was done using phytochemical analysis. The green synthesized gold nanoparticles show vibrant colours. They were characterized using UV–Visible spectroscopy, FT-IR spectroscopy, XRD analysis and FE-SEM. The analytical characterization methods ensured the formation of nanoparticles and could predict the nanometric size of the nanoparticles. The study also lay to determine the antibacterial potential of the TB fruit parts and TB fruit parts mediated gold nanoparticles. The pathogens chosen for the study were pathogens from clinical species such as Acinetobacter pneumonia, Bacillus subtilis, and Enterococcus faecalis which cause common infections. The TB fruit part extracts, as well as TB fruit parts mediated gold nanoparticles were capable enough to destroy clinical pathogens.Supplementary InformationThe online version contains supplementary material available at 10.1007/s12088-021-00937-3.  相似文献   

5.
Recently, various studies have focused on the development of multifunctional non-woven polyethylene terephthalate (PT; polyester) textiles. Herein, we introduce multifunctional non-woven polyester fabrics by pad dry curing silver nitrate (AgNO3) and aniline monomer into plasma-pretreated non-woven PT textile. This creates a nanocomposite layer of silver nanoparticles (AgNPs) and polyaniline (PANi) on the fabric surface. In order to prepare a non-woven fibrous mat, we applied the melt-spinning technique on previously shredded recycled PT plastic waste. On the surface of the cloth, PANi was synthesized by REDOX polymerization of aniline. Due to the oxidative polymerization, the silver ions (Ag+) were converted to Ag0NPs. PANi acted as a conductor while AgNPs inhibited the growth of microorganisms. Microwave-assisted curing with trimethoxyhexadecylsilane (TMHDS) gave PT textiles with superhydrophobic properties. The morphological studies were performed using Fourier-transform infrared (FTIR) spectroscopy, scanning electron microscopy (SEM), transmission electron microscopy (TEM), and energy-dispersive X-ray spectroscopy (EDX). The stiffness and breathability of finished non-woven PT textile materials were analyzed to establish their comfort levels. Both of Escherichia coli and Staphylococcus aureus were used to test the efficacy of the AgNPs-treated textiles as antimicrobial materials. Moreover, the processed polyester textiles showed excellent electrical conductivity and great ultraviolet-ray blocking.  相似文献   

6.

Background  

Multifunctional magnetic nanoparticles are important class of materials in the field of nanobiotechnology, as it is an emerging area of research for material science and molecular biology researchers. One of the various methods to obtain multifunctional nanomaterials, molecular functionalization by attaching organic functional groups to nanomagnetic materials is an important technique. Recently, functionalized magnetic nanoparticles have been demonstrated to be useful in isolation/detection of dangerous pathogens (bacteria/viruses) for human life. Iron (Fe) based material especially FePt is used in the isolation of ultralow concentrations (< 102 cfu/ml) of bacteria in less time and it has been demonstrated that van-FePt may be used as an alternative fast detection technique with respect to conventional polymerase chain reaction (PCR) method. However, still further improved demonstrations are necessary with interest to biocompatibility and green chemistry. Herein, we report the synthesis of Fe3O4 nanoparticles by template medication and its application for the detection/isolation of S. aureus bacteria.  相似文献   

7.
The agricultural wastes adversely affect the environment; however, they are rich in polyphenols; therefore, this study aimed to employ polyphenol-enriched waste extracts for silver nanoparticles synthesis, and study the larvicidal activity of silver nanoparticles fabricated by pomegranate and watermelon peels extracts (PPAgNPs and WPAgNPs) against all larval instars of Spodoptera littoralis. The polyphenol profile of pomegranate and watermelon peel extracts (PP and WP) and silver nanoparticles was detected by HPLC. The antioxidant activity was estimated by DPPH, and FARP assays and the antimicrobial activity was evaluated by disc assay. The Larvicidal activity of AgNPs against Egyptian leaf worm was performed by dipping technique. The obtained AgNPs were spherical with size ranged 15–85 nm and capped with proteins and polyphenols. The phenolic compounds in silver nanoparticles increased about extracts; therefore, they have the best performance in antioxidant/reducing activity, and inhibit the growth of tested bacteria and yeast. The PPAgNPs were the most effective against the first instar larvae instar (LC50 = 68.32 µg/ml), followed by pomegranate extract with (LC50 = 2852 µg/ml). The results indicated that obvious increase in polyphenols content in silver nanoparticles enhance their larvicidal effect and increasing mortality of 1st larval of S. littoralis Egyptian leafworms causing additive effect and synergism. We recommend recycling phenolic enriched agricultural wastes in producing green silver nanoprticles to control cotton leafworm that causes economic loses to crops.  相似文献   

8.
Allium cepa and garlic Allium sativa plants were used to evaluate their potential synthesis of silver nanoparticles and their antibacterial effect on Streptococcus pneumoniae and Pseudomonas aeruginosa. Transmission electron microscopy (SEM) was used to distinguish the morphology of the nanoparticles attained from plant extracts. Energy dispersive X-ray (EDX) spectrometer established the existence of elemental sign of the silver and homogenous allocation of silver nanoparticles. Diffraction by using X ray (XRD) analysis for the formed AgNPs revealed spherical plus cubical shapes structure with different planes ranged between 111 and 311 planes. The antibacterial action of AgNPs against vaginal pathogens, Streptococcus pneumoniae and Pseudomonas aeruginosa was recognized. Our work showed a rapid, eco-safety and suitable method for the synthesis of AgNPs from Allium cepa and garlic Allium sativa extracts and can be used in biomedical applications.  相似文献   

9.
Au nanostructures: an emerging prospect in cancer theranostics   总被引:1,自引:0,他引:1  
Au nanoparticles have been used in biomedical applications since ancient times. However, the rapid development of nanotechnology over the past century has led to recognition of the great potential of Au nanoparticles in a wide range of applications. Advanced fabrication techniques allow us to synthesize a variety of Au nanostructures possessing physiochemical properties that can be exploited for different purposes. Functionalization of the surface of Au nanoparticles further eases their application in various roles. These advantages of Au nanoparticles make them particularly suited for cancer treatment and diagnosis. The small size of Au particles enables them to preferentially accumulate at tumor sites to achieve in vivo targeting after systemic administration. Efficient light absorption followed by rapid heat conversion makes them very promising in photothermal therapy. The facile surface chemistry of Au nanoparticles eases delivery of drugs, ligands or imaging contrast agents in vivo. In this review, we summarize recent development of Au nanoparticles in cancer theranostics including imaging-based detection, photothermal therapy, chemical therapy and drug delivery. The multifunctional nature of Au nanoparticles means they hold great promise as novel anti-cancer therapeutics.  相似文献   

10.
The plant Cassia angustifolia belongs to Saudi Arabia, which is one of the native places and now cultured throughout the global countries. Medical care in the Arab world is an essential outlet for medicinal plants, both because they are crucial elements for prophetic medicine and due to their lengthy background in the Middle East. C.angustifolia is one of the medicinal plants used in the Saudi Arabia. The usage of plant extracts for synthesizing nanoparticles is conducive to other biological material, since it avoids the lengthy phase of cell culture maintenance. Silver nanoparticles attract further attention due to their strong conductivity, stability and antimicrobial activity across different metal nanoparticles. The present study was designed in the Saudi C. angustifolia leaves with the zinc synthesis of nanoparticles and its antibacterial ability. The plant extracts of C. angustifolia was used for synthesis of zinc nanoparticles, antimicrobial activities against bacterial strains have been tested along with transmission electron microscope (TEM), UV spectroscopy and antimicrobial activities have been conducted. This study showed that silver ions may be transferred from the plant extract to silver nanoparticles. AgNPs biogenic capacity to antibacterial with lovo cell with IC50 ranged from 33.5 ± 0.2 μg/mL demonstrated strong antibacterial capacity to antibody. The overall absorption value for the extract was between 420 and 440 nm and the color transition to green was the plasma absorption of the AgNPs. TEM results was showed in 200,000 magnification. The uniqueness of the current study is that Cassia angustifolia leaf extract from Saudi Arabia was used to prepare the metallic nanoparticles. Additionally, ZnCl2 may also be used as nanoparticles of mineral salt and zinc, which, since their application has been confirmed, are antimicrobial.  相似文献   

11.

Objective

To develop a high-sensitivity immunochromatographic test for fumonisin B1 in plant extracts.

Results

Unlike conventional immunochromatographic tests, this assay is performed in two stages: competitive reaction with free specific antibodies and identifying immune complexes by their interaction with the anti-species antibody-conjugated gold nanoparticles. The use of a new geometry for the test strip membranes and a novel reagent application method ensures the proper order of these stages without additional manipulations. The contact of the ready-to-use test strip with the liquid sample suffices in initiating all stages of the assay and obtaining test results. The developed test was used on corn extracts; its instrumental limit of fumonisin B1 detection was 0.6 ng ml?1 at 15 min of assay duration.

Conclusions

The proposed approach is flexible and can be used for a wide range of low molecular compounds. The use of anti-species antibody-conjugated gold nanoparticles in immunochromatography significantly facilitates the development of test systems by eliminating the need to synthesize and characterize the conjugates with specific antibodies for each new compound to be detected.
  相似文献   

12.

Background

Ashwagandha, a traditional Indian herb, has been known for its variety of therapeutic activities. We earlier demonstrated anticancer activities in the alcoholic and water extracts of the leaves that were mediated by activation of tumor suppressor functions and oxidative stress in cancer cells. Low doses of these extracts were shown to possess neuroprotective activities in vitro and in vivo assays.

Methodology/Principal Findings

We used cultured glioblastoma and neuroblastoma cells to examine the effect of extracts (alcoholic and water) as well as their bioactive components for neuroprotective activities against oxidative stress. Various biochemical and imaging assays on the marker proteins of glial and neuronal cells were performed along with their survival profiles in control, stressed and recovered conditions. We found that the extracts and one of the purified components, withanone, when used at a low dose, protected the glial and neuronal cells from oxidative as well as glutamate insult, and induced their differentiation per se. Furthermore, the combinations of extracts and active component were highly potent endorsing the therapeutic merit of the combinational approach.

Conclusion

Ashwagandha leaf derived bioactive compounds have neuroprotective potential and may serve as supplement for brain health.  相似文献   

13.
Leishmaniasis is a group of infectious and noncontagious severe parasitic diseases, caused by protozoans of the Leishmania genus. Natural products characterize a rich source of prospective chemical entities for the development of new effective drugs for neglected diseases. Scientific evaluation of medicinal plants has made it possible to use some metabolites from flavonoids and polyphenols compounds for the treatment of parasitic diseases. Therefore, we aimed in the present study to evaluate the protective effect of silver nanoparticles (Ag-NPs) biosynthesized using Fig and Olive extracts (NFO) against Cutaneous leishmaniasis in female Balb/c mice. A total of 70 mice were used and divided into seven groups. Treatment was initiated when local lesions were apparent, we found that Fig and Olive extracts were found to be a good source for the synthesis of (Ag-NPs), their formation was confirmed by color change and stability in solution. Nanoparticles biosynthesized using Fig and Olive extracts induced a reduction in the average size of cutaneous leishmaniasis lesions compared with the untreated mice. Moreover, nanoparticles treatment decreased oxidative stress (LPO, NO), down-regulation gene expression levels (TNF-α, IL-1β, and BAX), and this antileishmanial activity of nanoparticles was associated with enhanced antioxidant enzyme activities. In addition, histopathological evaluation proved the antileishmanial activity of nanoparticles compared with the positive control.Therefore, we aimed in the present study to evaluate the protective effect of silver nanoparticles biosynthesized using Fig and Olive extracts against cutaneous lesions induced by Leishmania major infection through their anti-inflammatory, antioxidant activities, and faster clinical efficacy than standard pentavalent antimonial treatment.  相似文献   

14.

Background

In this study, an attempt has been made with the advent of technology to prepare a multifunctional nanobiocomposite (NBC) for targeted drug delivery in cancer therapy.

Methods

Collagen (C) was fabricated as nanofibers with multifunctional moieties viz. CFeAb*D by incorporating iron oxide nanoparticles (Fe), coupling with fluorescein isothiocyanate (FITC) labeled antibody (Ab*) and loading an anticancer gemcitabine drug (D). This NBC was characterized by conventional methods and evaluated for its biological activities.

Results

The UV–vis and FTIR spectroscopic studies revealed the fluorescein to protein ratio and revealed the presence of iron oxide nanoparticles and their interaction with the collagen molecules, respectively. While SDS-PAGE showed the proteinaceous nature of collagen, VSM and TEM studies revealed magnetic saturation as 54.97 emu/g and a magnetic nanoparticle with a diameter in the range of 10–30 nm and the dimension of nanofiber ranging from 97 to 270 nm. A MRI scan has shown a super paramagnetic effect, which reveals that the prepared NBC can be used as a MRI contrast agent. The MTT assay has shown biocompatibility and an apoptotic effect while phase contrast microscopy exhibited receptor mediated uptake of endocytosis.

Conclusion

The novelty in the prepared NBC lies in the collagen nanofibers, which have a higher penetrating property without causing much cell damage, biocompatibility and multifunctional properties and is able to carry multifunctional agents.

General significance

The study has demonstrated the possible use of CFeAb*D as a multifunctional NBC for biomedical applications.  相似文献   

15.
硫化铜是一种二价铜的硫化物,可以作为半导体材料,化学式为CuS,呈黑褐色,溶解度极低。硫化铜纳米粒子(Copper sulfide nanoparticles, CuS NPs)是纳米尺度大小的硫化铜。近年来,CuS NPs因其结构的可塑性,良好的光热稳定性、生物相容性、突出的光热及光声转换性能,成为了当今纳米材料医学领域的研究热点,在肿瘤诊断和治疗领域中引起了广泛关注。CuS NPs本身可通过介质鳌合金属离子合成多功能纳米粒子,实现肿瘤多模式诊断,并且在光热治疗研究中体现出突出的治疗效果。本文综述了近几年CuS NPs在肿瘤诊断与治疗方面的研究进展,总结肿瘤治疗中的应用研究方法,对CuS NPs在生物医学领域应用中存在的问题进行分析,为解决实际操作过程所遇到的问题提供参考。  相似文献   

16.
In the current investigation, we report the biosynthesis of silver nanoparticles (Ag NPs) employing extract of Alternaria alternata, which is an eco-friendly process for the synthesis of metallic nanoparticles. Ag NPs were synthesised through the reduction of aqueous Ag+ ion using the cell extract of fungus A. alternata in the dark conditions. The synthetic process was relatively fast and Ag NPs were formed within 24 h. UV–visible spectrum of the aqueous medium containing silver ion showed a peak at 435?nm corresponding to the plasmon absorbance of Ag NPs and another peak at 280?nm refers to tyrosine amino acid. The nanoparticles were characterised by scanning electron microscopy (SEM) and Fourier transform infrared spectroscopy (FTIR). The morphology of nanoparticles is found to be spherical mostly, with ranging size of 27–79?nm; as revealed by SEM. The FTIR spectrum analysis indicated that biomolecules were involved in the synthesis of Ag NPs. The presence of the amino groups is expected to pack differently around the Ag NPs. This in turn will influence the self-assembly of nanoparticles on substrates as well as their stability. The present study demonstrates the possible use of biologically synthesised Ag NPs in the field of agriculture, when A. alternata could be used for simple, nonhazardous and efficient synthesis of Ag NPs.  相似文献   

17.
Many methods of synthesizing silver nanoparticles (Ag-NPs) by reducing Ag+ ions using aqueous/organic extracts of various plants have been reported in the past, but the methods are rather slow. In this investigation, silver nanoparticles were quickly synthesized from aqueous silver nitrate through a simple method using leaf extract of a plant—Cynodon dactylon which served as reducing agent, while sunlight acted as a catalyst. The formation of Ag-NPs was indicated by gradual change in colour and pH and confirmed by ultraviolet–visible spectroscopy. The Ag-NPs showed a surface plasmon resonance at 451 nm. Based on the decrease in pH, a possible mechanism of the synthesis of Ag-NPs involving hydroxyl (OH?) ions of polyphenols of the leaf extract is postulated. Ag-NPs having (111) and (200) crystal lattices were confirmed by X-ray diffraction. Scanning electron microscopy revealed the spherical nature of the Ag-NPs, while transmission electron microscopy showed that the nanoparticles were polydispersed with a size range of 8–10 nm. The synthesized Ag-NPs also demonstrated their antibacterial activity against Escherichia coli, Pseudomonas aeruginosa, Staphylococcus aureus and Salmonella typhimurium.  相似文献   

18.
Current study investigated the nematicidal activity of leaf extracts of Conyza dioscoridis, Melia azedarach, and Moringa oleifera that were prepared as silver nanoparticles (Ag-NP). The characterisation and size confirmation of the Ag-NP were done by UV–vis spectrophotometry and the scanning electron microscopy (SEM). The phytochemical contents of crude extracts and the nano formulations were analysed using gas chromatography-mass spectroscopy (GC-MS). Results revealed that silver nanoparticles of C. dioscoridis extractives had great nematicidal activity against the 2nd stage juvenile (J2) and eggs of Meloidogyne incognita. Also, the Ag-NP showed similar nematicidal effect to the reference nematicide; rugby. The GC-MS analysis revealed the increase of certain metabolites due to the formulation of the Ag-NPs. Aromadendrene, 1-hydroxy-1,7-dimethyl-4-isopropyl-2,7-cyclodecdiene, 6-epi-shyobunol, 4-hexylacetophenone, β-isocomene, caryophyllene, β- and α-selinene, α-cadinol, berkheyaradulen, and bis-(2-ethylhexyl)phthalate were increased more than 2.5-folds in the Ag-NP compared the extract. Therefore, the green synthesis of metal nanoparticles might be a safe, effective and affordable nematicide alternatives.  相似文献   

19.
Green synthesis method using camomile extract was applied to synthesize silver nanoparticles to tune their antibacterial properties merging the synergistic effect of camomile and Ag. Scanning transmission electron microscopy revealed that camomile extract (CE) consisted of porous globular nanometer sized structures, which were a perfect support for Ag nanoparticles. The Ag nanoparticles synthesized with the camomile extract (AgNPs/CE) of 7 nm average sizes, were uniformly distributed on the CE support, contrary to the pure Ag nanoparticles synthesized with glucose (AgNPs/G), which were over 50 nm in diameter and strongly agglomerated. The energy dispersive X-ray spectroscopy chemical analysis showed that camomile terpenoids act as a capping and reducing agent being adsorbed on the surface of AgNPs/CE enabling their reduction from Ag+ and preventing them from agglomeration. Fourier transform infrared and ultraviolet–visible spectroscopy measurements confirmed these findings, as the spectra of AgNPs/CE, compared to pure CE, did not contain the 1109 cm?1 band, corresponding to –C–O groups of terpenoids and the peaks at 280 and 320 nm, respectively. Antibacterial tests using four bacteria strains showed that the AgNPs/CE performed five times better compared to CE AgNPs/G samples, reducing totally all the bacteria in 2 h.  相似文献   

20.
Green synthesis of nanoparticles has gained significant importance in recent years and has become the one of the most preferred methods. Also, green synthesis of nanoparticles is valuable branch of nanotechnology. Plant extracts are eco-friendly and can be an economic option for synthesis of nanoparticles. This study presents method the synthesis of silver nanoparticles using water extract of Arnicae anthodium. Formation of silver nanoparticles was confirmed by UV–visble spectroscopy, Fourier transform infrared spectroscopy and total reflection X-ray fluorescence analysis. The morphology of the synthesized silver nanoparticles was verified by SEM–EDS. The obtained silver nanoparticles were used to study their antimicrobial activity.  相似文献   

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