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1.
J Sci Food Agric ; 100(2): 874-884, 2020 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-31680264

RESUMO

BACKGROUND: The low cost of aminoglycoside (AMG) antibiotics facilitates their excessive use in animal husbandry and the agriculture sector. This scenario has led to the occurrence of residues in the food chain. After several years of AMG use in antibacterial therapy, resistance to streptomycin has begun to appear. Most of the detection methods developed for AMG antibiotics lacks specificity. A broad target specific nanoprobe would be ideal for detecting the entire class of AMGs. A rapid and sensitive method for the detection of AMGs is urgently needed. RESULTS: Gallic acid-coated silver nanoparticles (AgNPs) were demonstrated as a nanoprobe for the colorimetric detection of AMGs (yellow to orange / red). A linear dynamic range of 50-650 pmol L-1 was achieved readily by ratiometric spectrophotometry (A560 /A400 ) with a limit of detection (LOD) as low as 36 pmol L-1 . The amine-groups of the AMGs function as molecular linkers, so that electrostatic coupling interactions between neighboring particles drive the formation of AgNP aggregates. The assay can also be applied for the determination of streptomycin residues in serum and milk samples. CONCLUSION: This study revealed the potential of an AgNP probe for the rapid and cost-effective detection of low-molecular-weight target analytes, such as the AMGs. A ligand-induced aggregation of AgNPs coated with gallic acid was reported to be a rapid and sensitive assay for AMGs. Analysis of streptomycin was demonstrated with excellent picomolar-level sensitivity. Thus, the validated method can find practical applications in the ultrasensitive detection of AMGs in complex and diagnostic settings. © 2019 Society of Chemical Industry.


Assuntos
Antibacterianos/análise , Colorimetria/métodos , Resíduos de Drogas/análise , Leite/química , Soro/química , Estreptomicina/análise , Água/química , Animais , Antibacterianos/farmacologia , Bovinos , Colorimetria/instrumentação , Limite de Detecção , Nanopartículas Metálicas/química , Prata/química
2.
Sci Total Environ ; 698: 134133, 2020 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-31505348

RESUMO

The series of breakthroughs that have occurred within the realm of nanotechnology have been the source of several new products and technological interventions. One of the most salient examples in this regard is the widespread employment of titanium dioxide (TiO2) nanoparticles across a range of consumer goods. Given that waste is generated at every stage of the consumer-product cycle (from production to disposal), many items with TiO2 nanoparticles are likely to end up being discarded into water bodies. In order to understand the interaction of TiO2 NPs with aquatic ecosystem, the ecological fate and toxicity of TiO2 NPs was studied by exposing zebrafish embryos to a combination of abiotic factors (humic acid and clay) to assess its effect on the development of zebrafish embryos. The physiological changes were correlated with genetic marker analysis to holistically understand the effect on embryos development. Derjaguin-Landau-Verwey-Overbeek (DLVO) theory was used to analyze the interaction energy between TiO2 NPs and natural organic matter (NOM) for understanding the aggregation behavior of engineered nanoparticles (ENPs) in media. The study revealed that combination of HA and clay stabilized TiO2 NPs, compared to bare TiO2 and HA or clay alone. TiO2 NPs and TiO2 NPs + Clay significantly altered the expression of genes involved in development of dorsoventral axis and neural network of zebrafish embryos. However, the presence of HA and HA + clay showed protective effect on zebrafish embryo development. The complete system analysis demonstrated the possible ameliorating effects of abiotic factors on the ecotoxicity of ENPs.


Assuntos
Argila/química , Nanopartículas Metálicas/toxicidade , Titânio/toxicidade , Animais , Embrião não Mamífero , Desenvolvimento Embrionário/efeitos dos fármacos , Substâncias Húmicas/análise , Nanopartículas Metálicas/química , Titânio/química , Poluentes Químicos da Água/química , Poluentes Químicos da Água/toxicidade , Peixe-Zebra
3.
Bioelectrochemistry ; 131: 107352, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31494386

RESUMO

The designed synthesis of efficient materials can significantly enhance the performance of electrochemical immunoassay in the detection of diseases, pesticide residues and environmental pollutants. The hollow AgPt@Pt core-shell nanoparticles (AgPt@Pt HNs) have exhibited high catalytic efficiency to the hydrogen peroxide (H2O2) reduction for its high mass activity from their hollow structure. Their limitation of instability can be overcome by loading on polypyrrole nanosheet (PPy NS). Besides, PPy NS exhibits good conductivity, and there exists environmentally-friendly method for its synthetic. Thus, AgPt@Pt HNs loaded on PPy NS (AgPt@Pt HNs/PPy NS) exhibits high catalytic efficiency to the reduction of H2O2 and good stability. Furthermore, the quick electron transfer of AgPt@Pt HNs/PPy NS modified glassy carbon electrode has been evidenced by the finding that the large constant of apparent electron transfer rate has also enlarged the current signal when the amount of electron is invariant. The modified electrode has fabricated a label-free amperometric immunosensor to detect sensitively prostate-specific antigen (PSA) with H2O2 as the electroactive material. The immunosensor in hollow core-shell nanosheet structure exhibiting good detection performance of PSA shows its promising applications in the clinical diagnosis.


Assuntos
Técnicas Biossensoriais , Eletrodos , Ouro/química , Nanopartículas Metálicas/química , Nanoestruturas/química , Platina/química , Polímeros/química , Pirróis/química , Biomarcadores Tumorais/análise , Catálise , Peróxido de Hidrogênio/química , Limite de Detecção , Oxirredução , Antígeno Prostático Específico/análise
4.
J Colloid Interface Sci ; 559: 313-323, 2020 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-31675662

RESUMO

Antibiotic resistance is a common phenomenon observed during treatment with antibacterials. Use of nanozymes, especially those with synergistic enzyme-like activities, as antibacterials could overcome this problem, but their synthesis is limited by their high cost and/or complex production process. Herein, vanadium oxide nanodots (VOxNDs) were prepared via a one-step bottom-up ethanol-thermal method using vanadium trichloride as the precursor. VOxNDs alone possess bienzyme mimics of peroxidase and oxidase. Accordingly, highly efficient antibacterials against drug-resistant bacteria can be obtained through synergistic catalysis; the oxidase-like activity decomposes O2 to generate superoxide anion radical (O2-) and hydroxyl radicals (OH), and the intrinsic peroxidase-like activity can further induce the production of OH from external H2O2. Consequently, H2O2 concentration could decrease up to four magnitude orders with VOxNDs to achieve an antibacterial efficacy similar to that of H2O2 alone. Wound healing in vivo further confirms the high antibacterial efficiency, good biocompatibility, and application potential of the synergistic antibacterial system due to the "nano" structure of VOxNDs. The method of synthesis of nanodot antibacterials described in this paper is inexpensive, and the results of this study reveal the multi-enzymatic synergism of nanozymes.


Assuntos
Antibacterianos/química , Nanopartículas Metálicas/química , Óxidos/química , Compostos de Vanádio/química , Cicatrização/efeitos dos fármacos , Animais , Materiais Biocompatíveis/química , Materiais Biomiméticos/química , Catálise , Sobrevivência Celular/efeitos dos fármacos , Farmacorresistência Bacteriana/efeitos dos fármacos , Escherichia coli/efeitos dos fármacos , Células HeLa , Células Endoteliais da Veia Umbilical Humana , Humanos , Peróxido de Hidrogênio/química , Radical Hidroxila/química , Peroxidases/metabolismo , Ratos Sprague-Dawley , Staphylococcus aureus/efeitos dos fármacos
5.
J Colloid Interface Sci ; 558: 47-54, 2020 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-31580954

RESUMO

The unique antibacterial characteristics of Ag nanomaterials offer a wide potential range of applications, but achieving rapid and durable antibacterial efficacy is challenging. This is because the speed and durability of the antibacterial function make conflicting demands on the structural design: the former requires the direct exposure of Ag to the surrounding environment, whereas the durability requires Ag to be protected from the environment. To overcome this incompatibility, we synthesize sandwich-structured polydopamine shells decorated both internally and externally with Ag nanoparticles, which exhibit prompt and lasting bioactivity in applications. These shells are biocompatible and can be used in vivo to counter bacterial infection caused by methicillin-resistant Staphylococcus aureus superbugs and to inhibit biofilm formation. This work represents a new paradigm for the design of composite materials with enhanced antibacterial properties.


Assuntos
Antibacterianos/química , Materiais Biocompatíveis/química , Indóis/química , Nanopartículas Metálicas/química , Polímeros/química , Prata/química , Animais , Antibacterianos/farmacologia , Materiais Biocompatíveis/farmacologia , Escherichia coli/efeitos dos fármacos , Humanos , Masculino , Staphylococcus aureus Resistente à Meticilina/efeitos dos fármacos , Testes de Sensibilidade Microbiana , Ratos , Ratos Sprague-Dawley
6.
J Colloid Interface Sci ; 558: 106-114, 2020 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-31585219

RESUMO

Green synthesis of nanoparticles is becoming increasingly popular as a simple and environmentally friendly method. In this study, iron-based nanoparticles (Fe-NPs) were successfully prepared using a peanut skin extract, where the peanut skin as an agricultural waste product was easy to obtain in large quantities, relatively inexpensive and also environmentally friendly. The average particle size of the produced Fe-NPs changed with their post-synthesis drying conditions. Under vacuum drying at 60 °C, the smallest average particle size obtained was 10.6 nm. The synthesized Fe-NPs had a core shell-like structure, in which the core was composed of Fe0, and the shell was a layered coating composed of biomolecules (e.g. anthocyanins, flavonols, phenolic compounds, epicatechin), iron oxides, Fe coordination compounds and iron-carbon alloys. Thereafter Fe-NPs (2 g L-1) prepared under different drying conditions were evaluated for their ability to remove Cr(VI) from aqueous solutions at pH of 4.7 and 25 °C. Fe-NPs obtained under vacuum drying at 60 °C performed the best, removing 100% of Cr(VI), from a 10 mg L-1 aqueous solution of Cr(VI) in just one min. Desorption and reuse experiments show that the desorption rate of Cr using 16 M hydrochloric acid and the recycling rate reached 70.2 and 59.9%, respectively. A potential mechanism for Fe NP synthesis involving the formation of intermediate complexes, an electron transfer reaction and adsorption of non-reducing organic macromolecules at the solid-liquid interfaces was proposed.


Assuntos
Arachis/química , Cromo/química , Ferro/química , Nanopartículas Metálicas/química , Extratos Vegetais/química , Poluentes Químicos da Água/química , Adsorção , Química Verde
7.
Chemosphere ; 238: 124624, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31472353

RESUMO

The capacity of two iron-based nanomaterials, namely goethite nanospheres (nGoethite) and zero valent iron nanoparticles (nZVI), to immobilize As in a polluted soil was evaluated and compared. The composition and morphology of the products were studied by energy dispersive X-ray analysis and transmission electron microscopy, while zeta potential and average sizes were determined by dynamic light scattering. To assess As immobilization, soil subsamples were treated with nGoethite or nZVI at a range of Fe doses (0.5%, 2%, 5% and 10%) and then studied by the TCLP test and the Tessier sequential extraction procedure. The influence of both nanoparticles on As speciation was determined, as was impact on soil pH, electrical conductivity, Fe availability and phytotoxicity (watercress germination). For nZVI, notable results were achieved at a dose of 2% (89.5% decrease in As, TCLP test), and no negative effects on soil parameters were detected. Indeed, even soil phytotoxicity was reduced and only at the highest dose was a slight increase in As3+ detected. In contrast, excellent results were obtained for nGoethite at the lowest dose (0.2%) (82.5% decrease in As, TCLP test); however, soil phytotoxicity was increased at higher doses, probably due to a marked enhancement of electrical conductivity. For both types of nanoparticle, slight increases in Fe availability were observed. Thus, our results show that both nZVI and nGoethite have the capacity to effectively immobilize As in this brownfield. The use of lower doses of nGoethite emerges as a promising soil remediation strategy for soils affected by As pollution.


Assuntos
Arsênico/análise , Poluição Ambiental/análise , Recuperação e Remediação Ambiental/métodos , Nanopartículas Metálicas/química , Poluentes do Solo/análise , Solo/química , Ferro/química , Compostos de Ferro/química , Microscopia Eletrônica de Transmissão , Minerais/química , Espectrometria por Raios X
8.
Chemosphere ; 238: 124681, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31524618

RESUMO

Excess amount of cadmium (Cd) in arable soils and shortage of good quality water are the major abiotic factors affecting the crop yield which needs immediate solution to feed the increasing population worldwide. Recently, nanoparticles (NPs) are widely used in various industries including agriculture which is due to the unique properties of NPs. Among NPs, iron (Fe) NPs might be used to alleviate the abiotic stresses in crops but limited informations are available in the literature about the role of Fe-NPs in crops under metal stress. The present study was designed to highlight the efficiency of Fe-NPs on Cd accumulation in Cd and drought-stressed wheat. Wheat plants were grown in Cd-contaminated soil after the supply of different levels of Fe-NPs and two water regimes were introduced in the soil in latter growth stages of the plants. Cadmium and drought stress negatively affected the wheat photosynthesis, yield and caused oxidative stress in leaves with excess accumulation of Cd in grains and other plant tissues. The NPs improved the photosynthesis, yield, Fe concentrations and diminished the Cd concentrations in tissues. The NPs alleviated the oxidative stress in leaves and the efficiency depends on the NPs concentrations applied in the soil. The results obtained indicated that Fe-NPs may be employed aiming to get wheat grains with excess Fe and decreased Cd contents. However, field investigations with various sizes, shapes and levels of NPs are needed before final recommendations to the farmers.


Assuntos
Cádmio/análise , Secas , Nanopartículas Metálicas/química , Poluentes do Solo/análise , Triticum/crescimento & desenvolvimento , Produção Agrícola , Compostos Férricos/farmacologia , Estresse Oxidativo/efeitos dos fármacos , Fotossíntese/efeitos dos fármacos , Folhas de Planta/química , Solo/química
9.
Sci Total Environ ; 700: 134443, 2020 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-31655455

RESUMO

Worldwide, billions of people are at risk from viruses, parasites and bacteria transmitted by mosquitoes, ticks, fleas and other vectors. Over exploitation of chemical pesticides to overcome the mosquito borne diseases led to detrimental effects on environment and human health. The present research aims to explore bio-fabrication of metal silver nanomaterials using Rhazya stricta extract against deadly mosquito vectors and microbial pathogens. The phytochemical profile of the R. stricta extracts was studied by HPLC-MS and 1H NMR. Further, confirmation of the bio-fabricated silver nanoparticles (AgNPs) was carried out by UV-vis spectroscopy and characterization through FTIR, TEM, EDX, and XRD analyses. The R. stricta-fabricated AgNPs showed acute toxicity on key mosquito vectors from two different country (India and Kingdom of Saudi Arabia, KSA) strains, notably, with LC50 values of 10.57, 11.89 and 12.78 µg/ml on malarial, dengue and filarial key Indian strains of mosquito vectors, respectively, and 30.66 and 38.39 µg/ml on KSA strains of Aedes aegypti and Culex pipiens, respectively. In mosquito adulticidal activity, R. stricta extract alone exhibited LC50 values ranging from 304.34 to 382.45 µg/ml against Indian strains and from 738.733 to 886.886 against Saudi Arabian strains, while AgNPs LC50 boosted from 9.52 to 12.16 µg/ml and from 30.66 to 38.39 µg/ml, respectively. Moreover, it was noticed that at low concentration the tested AgNPs showed high growth retardation of important pathogenic bacteria such as Bacillus subtilis, Klebsiella pneumoniae and Salmonella typhi with inhibition zone diameters from 11.86 to 22.92 mm. In conclusion, the present study highlighted that R. stricta-fabricated AgNPs could be a lead material for the management of mosquito vector and microbial pathogens control.


Assuntos
Anti-Infecciosos/química , Apocynaceae , Inseticidas/química , Nanopartículas Metálicas/química , Mosquitos Vetores/efeitos dos fármacos , Extratos Vegetais/química , Prata/química , Anti-Infecciosos/toxicidade , Índia , Inseticidas/toxicidade , Dose Letal Mediana , Controle de Mosquitos/métodos , Extratos Vegetais/toxicidade
10.
J Photochem Photobiol B ; 201: 111657, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31706085

RESUMO

Parkinson's disease (PD) is a general neurodegenerative disorder which largely has an effect on the society of the aged populations. PD is distinguishedwith loss of dopaminergic (DA) neurons in the substantia nigra. The exceptional properties of gold nanoparticles (AuNPs) have fascinated great attention in biomedical applications. In this present study, we explored theprospective beneficial effects of AuNPs synthesized from Cinnamomum verum on PD. PD rat models were established through MPTP injection treatment and AuNPs was administered. Administration of AuNPs reduces effect of MPTP-induced oxidative stress and motor abnormalities observed in PD rats. In addition ELISA analysis demonstrated that AuNPs treatment significantly attenuates Tumor Necrosis Factor-α (TNF-α), Interleukin-1ß (IL-1ß) and Interleukin-6 (IL-6) expression levels. Consequently, we investigated TLR/NF-κB pathway to examine the function of AuNPs on MPTP- induced PD rats. We found that AuNPs suppressed the alterations in the pathway of TLR/NF-κB associated molecules in MPTP stimulated PD rats. Hence, our results suggest that AuNPs attenuates MPTP introduced motor disorders, oxidative stress, activated inflammatory cytokines and activated TLR/NF-κB signaling in PD rats. In conclusion, AuNPs ease PD symptoms by the inhibition of TLR/NF-κB signaling pathway and recommend promise approach in the treatment of neurodegenerative diseases such as PD.


Assuntos
Cinnamomum zeylanicum/química , Ouro/química , Intoxicação por MPTP/tratamento farmacológico , Nanopartículas Metálicas/uso terapêutico , Animais , Cinnamomum zeylanicum/metabolismo , Citocinas/metabolismo , Química Verde , Intoxicação por MPTP/patologia , Masculino , Nanopartículas Metálicas/química , Nanopartículas Metálicas/toxicidade , Camundongos , NF-kappa B/metabolismo , Estresse Oxidativo/efeitos dos fármacos , Extratos Vegetais/química , Ratos , Ratos Sprague-Dawley , Transdução de Sinais/efeitos dos fármacos , Receptores Toll-Like/metabolismo
11.
J Photochem Photobiol B ; 201: 111670, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31706087

RESUMO

Synthesis of nanoparticles using plant sources as reducing agent has become important, as physical and chemical methods are costlier and affects environment. Hence it is important to develop environment friendly nanoparticle synthesis by avoiding the use of toxic chemicals. The present study aimed to synthesize silver nanoparticles (Ag Nps) and gold nanoparticles (AuNps) using Musa acuminata colla flower and its pharmaceutical activity against extended spectrum beta-lactamase (ESBL) gene producing bacteria and anticancer efficacy. The synthesized Ag and Au NPs were analysed by means of UV-Vis, FTIR, XRD,SEM and EDAX evidenced the bioreduction of Ag+ ions to Ag0 and Au3+ ions to Au0 respectively. Both nanoparticles and flower extracts were studied for antibacterial activity of ESBL gene producing bacteria by disc diffusion and microdilution (Resazurin) method. In vitro anticancer efficacy (MCF-7) and toxicity (VERO) of AgNPs, AuNPs, aqueous extract and ethanol extract of flowers were performed by MTT assay. IC50 value for DPPH analysis was at 390 µg and 460 µg for ethanol and aqueous extract respectively. Total antioxidant content was found be 740 µg/mg and 460 µg/mg for ethanol and aqueous extract. GCMS analysis authenticated the existence of the compounds namely, 9,12-octadecadienoic acid(z,z)- and n-hexadecanoic acid in the crude extract of the samples. Among the samples, AgNPs had best antibacterial activity. AgNPs and AuNPs were confirmed by colour change to reddish brown and ruby red. Further ƛmax were obtained at 474 and 540 nm by UV - visible spectrum. SEM analysis revealed the particle size ranges from 12.6 to 15.7 nm for silver and 10.1 to 15.6 nm for gold nanoparticles. The EDAX spectrum shows a strong signal for elemental Ag and Au at ~ 3 keV and 1.5 keV. The XRD patterns for silver and gold nanoparticles at 36.701, 42.900, 63.281 and 76.398 corresponding to the lattice planes 2.4467, 2.1064, 1.46839, 1.24564 nm and 27.32, 36.7228, 39.56, 42.888, 63.253, 63.253, 65.02 and 76.383 corresponding to the lattice planes 3.262, 2.44530, 2.276, 2.1070, 1.46897, 1.4332 and 1.24585 nm. The IC50 values for MCF-7 and VERO cells were 30.0 µg/ml and 55.0 µg/ml respectively.


Assuntos
Antibacterianos/química , Antineoplásicos/química , Ouro/química , Musa/química , Prata/química , Animais , Antibacterianos/farmacologia , Antineoplásicos/farmacologia , Antioxidantes/química , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Flores/química , Flores/metabolismo , Bactérias Gram-Negativas/efeitos dos fármacos , Bactérias Gram-Positivas/efeitos dos fármacos , Química Verde , Humanos , Nanopartículas Metálicas/química , Nanopartículas Metálicas/toxicidade , Musa/metabolismo , Extratos Vegetais/química , Células Vero
12.
J Photochem Photobiol B ; 201: 111649, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31710925

RESUMO

In the present systematic study, silver nanoparticles have been synthesized using the fruits of Alpinia nigra. Apart from the presence of saponins, glycosides, alkaloids, steroids, the extract of A. nigra fruits are rich in polyphenols. The Total Flavonoid and Phenol Content of A. nigra fruits extract is 718 mgRE/g extract and 74.9 mgGAE/g extract respectively. The formation of the nanoparticles was validated through characterization techniques like UV-Vis spectroscopy, X- ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS) and Energy dispersive X-ray spectroscopy (EDX). The spherical shape of silver nanoparticles is observed in Transmission Electron Microscopy (TEM) images. The average particle size of the silver nanoparticles is 6 nm. The biomolecules of the fruit extract played the dual role of reducing and capping agents which is evident from Fourier Transform Infrared (FTIR) spectrometer and Scanning Electron Microscopy (SEM) image analysis. The A. nigra capped silver nanoparticles exhibited promising antimicrobial activity against gram negative bacteria Klebsiella pneumoniae, gram positive bacteria Staphylococcus aureus and the pathogenic fungus, Candida albicans. Amongst the three pathogens, Klebsiella pneumoniae is the most susceptible to silver nanoparticles. Furthermore, the nanoparticles efficiently catalysed the degradation of the anthropogenic dyes Methyl orange, Rhodamine B and Orange G in the presence of sunlight. The photocatalytic degradation process follows the pseudo-first order kinetics. These results confirm that the silver nanoparticles can be efficiently synthesized via a green route using A. nigra fruits with applications as antimicrobial and catalytic agents.


Assuntos
Alpinia/química , Anti-Infecciosos/síntese química , Nanopartículas Metálicas/química , Prata/química , Alpinia/metabolismo , Anti-Infecciosos/farmacologia , Compostos Azo/química , Catálise , Corantes/química , Frutas/química , Frutas/metabolismo , Bactérias Gram-Negativas/efeitos dos fármacos , Bactérias Gram-Positivas/efeitos dos fármacos , Química Verde , Nanopartículas Metálicas/toxicidade , Tamanho da Partícula , Extratos Vegetais/química , Luz Solar
13.
J Agric Food Chem ; 67(46): 12936-12944, 2019 Nov 20.
Artigo em Inglês | MEDLINE | ID: mdl-31670953

RESUMO

An ultrasensitive bio-barcode competitive immunoassay method based on droplet digital polymerase chain reaction (ddPCR) was developed for the determination of triazophos. Gold nanoparticles (AuNPs) were coated with monoclonal antibodies (mAbs) and complementary double-stranded DNA (dsDNA), which included bio-barcode DNA and thiol-capped DNA. Magnetic nanoparticle (MNP) probes were constructed by modifying the MNPs with ovalbumin-hapten conjugates (OVA-hapten). The target pesticide and OVA-hapten on the surface of the MNP probes competed with the AuNP probes simultaneously, and then the bio-barcode DNA was released for quantification by ddPCR. The concentration of released DNA was inversely proportional to the concentration of pesticide to be tested. Under the optimum conditions, the competitive immunoassay exhibited a wide linear range of 0.01-20 ng/mL and a low detection limit of 0.002 ng/mL. Spike recovery tests were carried out using apple, rice, cabbage, and cucumber samples to verify the feasibility of the method. The recovery and relative standard deviations (RSDs) of the technique ranged from 76.9 to 94.4% and from 10.8 to 19.9%, respectively. To further validate the results, a linear correlation analysis was performed between the proposed method and liquid chromatography-tandem mass spectrometry (LC-MS/MS). Consequently, the bio-barcode immunoassay based on nanoparticles and ddPCR, an ultrasensitive method, showed great potential for the determination of target pesticides in real samples.


Assuntos
Imunoensaio/métodos , Inseticidas/análise , Organotiofosfatos/análise , Reação em Cadeia da Polimerase/métodos , Triazóis/análise , DNA/genética , Ouro/química , Imunoensaio/instrumentação , Limite de Detecção , Magnetismo/métodos , Nanopartículas Metálicas/química
14.
J Photochem Photobiol B ; 200: 111635, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31671372

RESUMO

Parkinson disease is one of the most common neurological movement disorders affecting geriatric population. Biosynthesized gold nanoparticles are the ideal alternatives spotlighted by many researchers to treat various diseases. In the present study we synthesized gold nanoparticles using the root extract of Paeonia mountan, woody trees which are used in traditional Chinese medicine to be prescribed for diverse diseases. The synthesis of gold nanoparticles was confirmed with UV-Vis spectroscopic analysis and characterized using FTIR, HR-TEM, EDAX and XRD analysis. The cytotoxicity property of synthesized gold nanoparticles was assessed using MTT assay in the murine microglial BV2 cells. The neuroprotective effect of synthesized gold nanoparticles in inflammatory agent lipopolysaccharides triggered murine microglial BV2 cells was evaluated using nitric oxide, prostaglandin E2 and inflammatory cytokines assays such as IL-6&IL-1ß. Further to confirm in vivo effect of synthesized nanoparticles, the nanoparticles were treated to Parkinson induced C57BL/6 mice. Behavioral, biochemical and molecular analysis were performed to estimate the potency of synthesized gold nanoparticles against the Parkinson induction in mice model. Our characterization results prove the gold nanoparticles synthesized using Paeonia mountan fulfills the requirement of ideal nanodrug and it potentially inhibited the inflammation in in vitro murine microglial BV2. The results of in vivo experiments authentically confirm gold nanoparticles synthesized using Paeonia mountan alleviates the neuroinflammation and improves the motor coordination in Parkinson induced mice.


Assuntos
Ouro/química , Nanopartículas Metálicas/química , Fármacos Neuroprotetores/química , Paeonia/química , Extratos Vegetais/química , Animais , Anti-Inflamatórios/química , Anti-Inflamatórios/farmacologia , Anti-Inflamatórios/uso terapêutico , Antioxidantes/química , Linhagem Celular , Sobrevivência Celular/efeitos dos fármacos , Citocinas/metabolismo , Química Verde , Lipopolissacarídeos/farmacologia , Masculino , Nanopartículas Metálicas/uso terapêutico , Nanopartículas Metálicas/toxicidade , Camundongos , Camundongos Endogâmicos C57BL , Microglia/citologia , Microglia/efeitos dos fármacos , Microglia/metabolismo , Fármacos Neuroprotetores/farmacologia , Fármacos Neuroprotetores/uso terapêutico , Óxido Nítrico/metabolismo , Paeonia/metabolismo , Doença de Parkinson/tratamento farmacológico , Doença de Parkinson/patologia , Doença de Parkinson/veterinária , Raízes de Plantas/química , Raízes de Plantas/metabolismo
15.
Chem Commun (Camb) ; 55(93): 14039-14042, 2019 Dec 04.
Artigo em Inglês | MEDLINE | ID: mdl-31690924

RESUMO

In this work, we have proposed a new strategy to expand the function of a protein. By taking a protease as an example, it can be engineered to make up the shortcoming of natural proteases, and thus it can efficiently and selectively hydrolyze a desired protein even in a complex biological fluid.


Assuntos
Inibidores Enzimáticos/química , Nanoconjugados/química , Peptídeo Hidrolases/química , Aptâmeros de Nucleotídeos/química , DNA/química , Ouro/química , Nanopartículas Metálicas/química , Biologia Molecular/métodos , RNA/química
16.
J Photochem Photobiol B ; 201: 111643, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31698218

RESUMO

Diabetes is a major emerging health consequence across the world which directly associated with the obesity. Contemporary anti-diabetic drugs have numeral limitations, and investigation of herbal remedies for diabetes give novel guide for the expansion of new drugs that can be used as harmonizing to present anti-diabetic allopathic medications. Gold nanoparticles (AuNPs) of 21 nm have been formerly well portrayed in vitro for their capability to intend active uptake in cell. Our present study was dealing with the synthesis of gold nanoparticles by means of Smilax glabra rhizome amend the anti-obesity constraints in high-fat diet by streptozotocin provoked obese diabetes in rat model. Characterization studies like UV -Spectroscopy, XRD analysis, SEM, TEM microscopy, Energy Dispersive X-Ray Spectroscopy, and FT-IR investigation confirms the availability of dimension, shape and size. Biochemical parameters like blood glucose and insulin sufferance and its release, lipid profile, aterogenic & coronary index, liver markers, inflammatory markers, hormones like leptin, resistin, adiponectin indicates the therapeutic effect of gold nanoparticles harvested from Smilax glabra on obese and diabetic rats. Histopathological examinations displayed the disturbed internal structures of obese and diabetic rats liver and heart tissues. Whereas, treatment with gold nanoparticles synthesized from Smilax glabra restored the internal membrane, nuclei and cytoplasm. All these findings confirmed the anti-obesity and anti-diabetic effect of synthesized gold nanoparticles from Smilax glabra.


Assuntos
Diabetes Mellitus Experimental/patologia , Dieta Hiperlipídica , Ouro/química , Nanopartículas Metálicas/química , Smilax/química , Animais , Glicemia/análise , Diabetes Mellitus Experimental/induzido quimicamente , Diabetes Mellitus Experimental/tratamento farmacológico , Coração/efeitos dos fármacos , Fígado/efeitos dos fármacos , Fígado/metabolismo , Fígado/patologia , Masculino , Nanopartículas Metálicas/uso terapêutico , Nanopartículas Metálicas/toxicidade , Miocárdio/metabolismo , Miocárdio/patologia , Extratos Vegetais/química , Ratos , Ratos Wistar , Rizoma/química , Rizoma/metabolismo , Smilax/metabolismo , Estreptozocina/toxicidade
17.
J Photochem Photobiol B ; 200: 111650, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31698288

RESUMO

The biosynthesis of ZnO nanoparticles was synthesized by biogenic reduction of applied Cucurbita seed extract. The powder X-ray diffraction pattern displayed the high crystalline nature of synthesized ZnO nanoparticles and the crystallite size was calculated at 35 nm range. The Fourier Transform Infra-Red study revealed the functional groups of biogenic reduction and vibrational bands present in the synthesized nanoparticles. The UV-Visible analysis explained the SPR absorption peak at 371 nm. The Photoluminescence study revealed the strong red shoulder emission peak at 665 nm. The particle size analyzer displayed the particle size occupies majorly on 45-65 nm. The SEM analysis pointed the ZnO nanoparticles under rod, rectangular and hexagonal shapes were procured. The EDAX spectrum also mapping exposed the purity of formed ZnO nanoparticles with just Zn and O peaks. The HRTEM analysis exposed the hexagonal shape wurtzite structure ZnO particles formation. The physiochemical analysis revealed general nature of Cucurbita seed powder moreover which explained the phytochemicals involved in biogenic reduction of ZnO nanoparticles. The formed ZnO nanoparticles exhibited good antibacterial activity on E. coli, Bacillus pumilus, and Salmonella typhi bacteria. The cytotoxicity study stated the good toxicity on E. coli AB 1157. The antifungal activity showed a better effect on Aspergillus flavus and Aspergillus niger fungi. The antioxidant activity clarified the good free radical scavenging action. The anti larvicidal activity expressed a better impact on Culex tritaeniorhynchus mosquito larvae.


Assuntos
Cucurbita/química , Culex/efeitos dos fármacos , Nanopartículas Metálicas/toxicidade , Extratos Vegetais/química , Óxido de Zinco/química , Animais , Antibacterianos/biossíntese , Antibacterianos/química , Antibacterianos/farmacologia , Antifúngicos/química , Antifúngicos/metabolismo , Antifúngicos/farmacologia , Aspergillus niger/efeitos dos fármacos , Cucurbita/metabolismo , Culex/crescimento & desenvolvimento , Escherichia coli/efeitos dos fármacos , Química Verde , Larva/efeitos dos fármacos , Nanopartículas Metálicas/química , Tamanho da Partícula , Sementes/química , Sementes/metabolismo
18.
Chem Commun (Camb) ; 55(92): 13932-13935, 2019 Nov 14.
Artigo em Inglês | MEDLINE | ID: mdl-31686058

RESUMO

In this work, a bipedal DNA walker was employed to mediate an efficient enzyme-free exponential isothermal DNA signal amplification. On the basis of the bipedal DNA walker mediated enzyme-free exponential isothermal signal amplification, an electrochemiluminescence (ECL) biosensor was constructed for sensitive and rapid detection of microRNA (miRNA) with a limit of detection down to 0.24 fM and requiring less than 40 min.


Assuntos
Técnicas Biossensoriais/métodos , DNA/química , MicroRNAs/análise , Linhagem Celular Tumoral , Complexos de Coordenação/química , DNA/metabolismo , Humanos , Limite de Detecção , Medições Luminescentes , Nanopartículas Metálicas/química , Hibridização de Ácido Nucleico , Rutênio/química , Titânio/química
19.
J Photochem Photobiol B ; 201: 111624, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31722283

RESUMO

Biosynthesis of Zinc oxide nanoparticles (ZnONPs) from natural plants stands as a promising nanodrug delivery system in cancer therapeutics. Marsdenia tenacissima (M.t), a Chinese medicinal plant has been extensively used as clinical remedy for treating several types of cancer. In this present study, ZnONPs were synthesized from Marsdenia tenacissima and its anti cancer potency was assessed against in vitro laryngeal cancer cell line Hep-2. The biosynthesized Marsdenia tenacissima Zinc Oxide Nanoparticles [M.t-ZnONPs] was characterized using UV-visible Spec, SEM, TEM and EDAX analysis. The cytotoxic and apoptotic inducing potential of M.t-ZnONPs was assessed by MTT assay and staining such as DCFH-DA, AO/EtBr, Rhodamine 123, DAPI and comet assay. The anticancer potential of M.t-ZnONPs was analysed by Real time PCR analysis of proapoptotic, antiapoptotic and caspases proteins. Our present findings showed characteristic and morphological representation of synthesized M.t-ZnONPs by UV-visible Spec, SEM, TEM and EDAX analysis. M.t-ZnONPs exhibits its cytotoxicity by inhibiting the viability of Hep-2 cells and IC50 value was obtained by MTT assay. The results of apoptotic staining techniques in M.t-ZnONPs treated Hep-2 cells confirm with excess ROS generation, disruption of mitochondrial membrane potential and nuclear damage. The apoptotic inducing potential of M.t-ZnONPs was also evidenced by upregulation of proapoptotic proteins Bax, Caspase 3 & 9 and downregultion of antiapoptotic protein Bcl-2 by RT-PCR analysis. Finally, these results suggested that biosynthesized M.t-ZnONPs is an effective anticancer agent which induces apoptosis in Hep-2 laryngeal cell line and thus conclude that M.t-ZnONPs, a valid anticancer strategy in treating various cancer.


Assuntos
Apoptose/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Marsdenia/química , Nanopartículas Metálicas/toxicidade , Óxido de Zinco/química , Linhagem Celular Tumoral , Dano ao DNA/efeitos dos fármacos , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Química Verde , Humanos , Neoplasias Laríngeas/metabolismo , Neoplasias Laríngeas/patologia , Marsdenia/metabolismo , Potencial da Membrana Mitocondrial/efeitos dos fármacos , Nanopartículas Metálicas/química , Extratos Vegetais/química , Proteínas Proto-Oncogênicas c-bcl-2/genética , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , Espécies Reativas de Oxigênio/metabolismo
20.
J Photochem Photobiol B ; 201: 111667, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31683167

RESUMO

Titanium dioxide nanoparticles (TiO2-NPs) were synthesized using the aqueous leaf extract of Aloe barbadensis as a reducing and fabricating agent. The biosynthesis of the TiO2-NPs was initially confirmed by UV-vis spectroscopy. Based on the HRTEM and FESEM analysis, the biosynthesized NPs were found to be polydispersed and predominantly spherical in shape, with an average size of ~20 nm. A sharp and strong characteristic peaks of titanium (Ti) and oxygen (O) observed in the EDS pattern confirmed the synthesis of the TiO2-NPs. The FTIR spectroscopy suggested the presence of terpenoids, flavonoids and proteins which might be responsible for the biosynthesis and fabrication of the TiO2-NPs. The crystalline nature of the synthesized TiO2-NPs constituting of a mixture of brookite, anatase, and rutile phases was indicated by the XRD pattern. The spectral window around 180-1000 cm-1 covered the high-frequency Raman spectra of the TiO2-NPs. The Raman vibrational spectrum showed four Eg modes centered at 197.84, 399.24, 514.50, and 641.58 cm-1 representing the anatase phase of TiO2-NPs. The strongest and broadened peak of anatase was observed at the frequency of 641.58 cm-1. The metabolic activity of P. aeruginosa exposed to the MIC of TiO2-NPs was measured based on the reduction of tetrazolium salt by the dehydrogenase enzyme, produced by the metabolically active bacterial cells. The reduction in TTC was evident from the appearance of a red colored formazan in the solution. A noticeable suppression in the cell viability by 30.76 ±â€¯3.96% of P. aeruginosa in the biofilm mode was found in presence of TiO2-NPs. Furthermore, the Minimum Inhibitory Concentration (MIC) of TiO2-NPs exhibited profound antibiofilm activity against P. aeruginosa by effectively preventing the adherence of the planktonic cells to the substratum. Thus, these NPs may be employed in controlling bacterial infections associated with biofilm.


Assuntos
Aloe/química , Biofilmes/efeitos dos fármacos , Nanopartículas Metálicas/toxicidade , Pseudomonas aeruginosa/fisiologia , Titânio/química , Aloe/metabolismo , Química Verde , Nanopartículas Metálicas/química , Testes de Sensibilidade Microbiana , Tamanho da Partícula , Extratos Vegetais/química , Folhas de Planta/química , Folhas de Planta/metabolismo
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