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1.
Int J Mol Sci ; 24(14)2023 Jul 18.
Artigo em Inglês | MEDLINE | ID: mdl-37511354

RESUMO

This review mainly addresses applications of polymer/graphene nanocomposites in certain significant energy storage and conversion devices such as supercapacitors, Li-ion batteries, and fuel cells. Graphene has achieved an indispensable position among carbon nanomaterials owing to its inimitable structure and features. Graphene and its nanocomposites have been recognized for providing a high surface area, electron conductivity, capacitance, energy density, charge-discharge, cyclic stability, power conversion efficiency, and other advanced features in efficient energy devices. Furthermore, graphene-containing nanocomposites have superior microstructure, mechanical robustness, and heat constancy characteristics. Thus, this state-of-the-art article offers comprehensive coverage on designing, processing, and applying graphene-based nanoarchitectures in high-performance energy storage and conversion devices. Despite the essential features of graphene-derived nanocomposites, several challenges need to be overcome to attain advanced device performance.


Assuntos
Líquidos Corporais , Grafite , Nanocompostos , Carbono , Capacitância Elétrica
2.
Biotechnol Lett ; 43(4): 781-790, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33387115

RESUMO

In the present work, we propose the synthesis of novel nicotinamide subsituted phthlocyanine photosensitizer (PS) and characterized by FTIR, UV-visible, H-NMR and MALDI Toff spectroscopy. Nicotinamide plays a vital rule in the central nervous system and its potential as a therapeutic for neurodegenerative disease. Nicotinamide substituted PS (3) efficiently produced ROS via type-1 process as measured by DCF assay. We observed that our PS after red light illumination (22 J/cm2) killed gram positive S. aureus upto 3 log reduction. Furher the addition of Potassium Iodide (100 mM) significantly potentiated PS at lower concentrations and enhanced the bacterial killing upto 6 log reduction against the S. aureus. We further found that the synergistic effect of PS and KI also eradicated the gram negative E. coli strain at lower concentraion of PS and found to killed E. coli upto 5 log reduction under the red light illumination at 22 J/cm2 of light dose. The conjugation of such biologically important form of vitamin B3 with PS would be a great addition and could pav the way for the novel photodynamic agent in the treatement of cancer and infectious diseases. A new symmetrical Nicotinamide tetrasubstituted zinc phthalocyanine (3) was synthesized. Upon addition of potassium Iodide with PS, the PS exhibited significant photodynamic activity with 5-6 logs reduction in bacterial load was achieved.


Assuntos
Escherichia coli/crescimento & desenvolvimento , Isoindóis/síntese química , Niacinamida/química , Iodeto de Potássio/farmacologia , Staphylococcus aureus/crescimento & desenvolvimento , Sinergismo Farmacológico , Escherichia coli/efeitos dos fármacos , Isoindóis/química , Isoindóis/farmacologia , Testes de Sensibilidade Microbiana , Viabilidade Microbiana/efeitos dos fármacos , Fotoquimioterapia , Fármacos Fotossensibilizantes/síntese química , Fármacos Fotossensibilizantes/química , Fármacos Fotossensibilizantes/farmacologia , Staphylococcus aureus/efeitos dos fármacos
3.
Int J Mol Sci ; 22(22)2021 Nov 22.
Artigo em Inglês | MEDLINE | ID: mdl-34830442

RESUMO

Herein, we report the green synthesis of silver nanoparticles (OE-Ag NPs) by ecofriendly green processes using biological molecules of Olea europaea leaf extract. Green synthesized OE-Ag NPs were successfully characterized using different spectroscopic techniques. Antibacterial activity of OE-Ag NPs was assessed against four different bacteriological strains using the dilution serial method. The cytotoxic potential was determined against MCF-7 carcinoma cells using MTT assay in terms of cell viability percentage. Antioxidant properties were evaluated in terms of 2,2-diphenyl-1-picrylhydrazyl (DPPH) free radical scavenging. Biocompatibility was further examined by incubating the synthesized NPs with hMSC cells for 24 h. The results were demonstrated that synthesized OE-Ag NPs presented excellent log10 reduction in the growth of all the tested bacterial strains, which as statistically equivalent (p > 0.05) to the standard antibiotic drug. Moreover, they also demonstrated excellent cytotoxic efficacy against the MCF-7 carcinoma cells compared to plant lead extract and Com-Ag NPs. Green synthesized OE-Ag NPs appeared more biocompatible to hMSC and 293T cells compared to Com-Ag NPs. Excellent biological results of the OE-Ag NPs might be attributed to the synergetic effect of NPs' properties and the adsorbed secondary metabolites of plant leaf extract. Hence, this study suggests that synthesized OE-Ag NPs can be a potential contender for their various biological and nutraceutical applications. Moreover, this study will open a new avenue to produce biocompatible nanoparticles with additional biological functionalities from the plants.


Assuntos
Química Verde , Nanopartículas Metálicas/química , Extratos Vegetais/farmacologia , Antibacterianos/química , Antibacterianos/farmacologia , Antineoplásicos/química , Antineoplásicos/farmacologia , Antioxidantes/química , Antioxidantes/farmacologia , Bactérias/efeitos dos fármacos , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Humanos , Testes de Sensibilidade Microbiana , Olea/química , Extratos Vegetais/química , Prata/química
4.
Microb Pathog ; 134: 103579, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31175970

RESUMO

Synthesis of highly efficient antibacterial agents has become highly important due to emergence of antibiotic resistance. Herein, Pristine ZnO and ZnO-CuO nanocomposite has been synthesized by simple chemical co-precipitation method and characterized by X-ray diffraction (XRD), microscopic and spectroscopic techniques. The prepared ZnO-CuO nanocomposite is composed of two dimensional nanosheets consisting of hexagonal ZnO and monoclinic CuO crystal phases present in coexistence. Moreover, a minute presence of Cu5Zn8 cubic phase has been evident in the XRD pattern of ZnO-CuO nanocomposite. Fourier Transform Infrared Spectroscopy (FTIR) spectrum of the prepared nanocomposite has revealed the presence of vibrational modes related to both Zn-O and Cu-O. Photoluminescence (PL) investigations depicted the formation of huge amounts of surface defects in ZnO-CuO nanocomposite as compared to pristine ZnO nanostructures. The prepared ZnO-CuO nanocomposite has efficiently killed Methicillin resistant Staphylococus aureus (s. aureus) bacterium by producing 24 mm of zone of inhibition (ZOI) comparing to 8 mm ZOI produced by pristine ZnO. The superior antibacterial activity of ZnO-CuO nanocomposite has been attributed to oxidative stress generated by electron transfer pathway and reactive oxygen species (ROS) generation.


Assuntos
Antibacterianos/farmacologia , Precipitação Química , Cobre/farmacologia , Nanocompostos/química , Óxido de Zinco/farmacologia , Antibacterianos/química , Bactérias/efeitos dos fármacos , Cobre/química , Luminescência , Testes de Sensibilidade Microbiana , Tamanho da Partícula , Espécies Reativas de Oxigênio/metabolismo , Espectrometria de Fluorescência , Espectrofotometria Infravermelho , Espectroscopia de Infravermelho com Transformada de Fourier , Staphylococcus aureus/efeitos dos fármacos , Difração de Raios X
5.
J Microsc ; 265(2): 214-221, 2017 02.
Artigo em Inglês | MEDLINE | ID: mdl-27682151

RESUMO

Vanadium pentoxide V2 O5 thin films were grown at room temperature on ITO coated glass substrates by electrochemical deposition. The resulting films were annealed at 300, 400 and 500°C for 1 h in ambient environment. The effect of heat treatment on the films properties such as surface morphology, crystal structure, optical absorption and photoluminescence were investigated. The x-ray diffraction study showed that the films are well crystallized with temperatures. Strong reflection from plane (400) indicated the film's preferred growth orientation. The V2 O5 films are found to be highly transparent across the visible spectrum and the measured photoluminescence quenching suggested the film's potential application in OPV device fabrication.

6.
Environ Monit Assess ; 186(12): 8587-98, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-25252792

RESUMO

The morphology, microstructure, and chemical composition of a variety of particles emitted from coal-fired power plants, steel plants, and vehicle exhausts, which are possible sources of particulate matter (PM) in the atmosphere, were investigated by scanning electron microscopy (SEM) and transmission electron microscopy (TEM) and compared with particle samples collected from urban atmosphere to identify the best footprint or the suitable indicator relating the existence of studied particles and their possible emitters by the morphology, microstructure, and chemical composition of the particles. The investigation indicated that the particles from these three sources are different in morphology, microstructure, and chemical composition. Sphere aggregates were generally the most abundant components, with silicon and aluminum as major elements. The urban air particulate contained particles similar to those observed in the power plant, steel plant, and vehicle exhaust samples suggesting that all three sources are contributing to the pollution in the city.


Assuntos
Poluentes Atmosféricos/análise , Monitoramento Ambiental , Material Particulado/análise , Atmosfera/química , China , Cidades , Microscopia Eletrônica de Varredura , Tamanho da Partícula , Centrais Elétricas , Aço , Emissões de Veículos/análise
7.
RSC Adv ; 13(30): 21008-21020, 2023 Jul 07.
Artigo em Inglês | MEDLINE | ID: mdl-37441046

RESUMO

Araldite LY5052 epoxy resin and Aradur HY5052 hardener were used in a ratio of 100 : 38 to produce composite coatings containing 0.05 proportion of functionalized SiO2. Coating samples were cured at curing temperatures of 60, 80, 100, 120, and 140 °C. The results of Fourier Transform Infrared Spectroscopy (FTIR) verified that silica particles were successfully functionalized with methyltrimethoxysilane (MTMS)/3-aminopropyl-triethoxysilane (APTES). The epoxide and Si-O bond peaks in the EHS100 coating were present due to the effective incorporation of functionalized silica (FSiO2) particles in the polymeric matrix (epoxy resin). The surface morphology of the bare aluminium alloy AA7075 and EHS100 coating was investigated by Field Emission Scanning Electron Microscopy (FE-SEM). Additionally, corrosion analysis was conducted at room temperature using an electrolytic solution of artificial seawater, prepared according to ASTM standard D1141-98. Charge transfer resistance (Rct) was shown to increase by 86.43, 92.15, 94.76, 90.65, and 83.96% for EHS60, EHS80, EHS100, EHS120, and EHS140 in comparison to bare AA7075 substrate using electrochemical impedance spectroscopy (EIS) examination. Furthermore, potentiodynamic polarization (PDP) measurements were carried out to determine the corrosion rates, which demonstrated a drop of 55.98, 98.96, 99.37, 98.33, and 50.39% for EHS60, EHS80, EHS100, EHS120, and EHS140, as compared to the bare AA7075 sample. The highest charge transfer resistance (29.77 kΩ) and lowest corrosion rate (0.00078 mm per year) were recorded for EHS100, which reveals that the EHS100 coating has the best anti-corrosion performance and provides the maximum corrosion protection for the aluminium alloy AA7075 substrate.

8.
ACS Omega ; 8(24): 21689-21695, 2023 Jun 20.
Artigo em Inglês | MEDLINE | ID: mdl-37360418

RESUMO

Iron-based materials are among the most commonly used oxygen scavengers. Here, we investigated the mesoporous silica nanosphere (MSN)-supported iron-based scavengers, such as FeOx nanoparticles and different atomic layer deposition (ALD) coatings (FeOx and Fe). We found that the scavenger performance is a result of a complex interplay between available Brunauer-Emmett-Teller surface area and the scavenger composition, with the combination of infiltrated nanoparticles and Fe-ALD coating resulting in the best performance. When the glucose-based treatment of MSN is used to further enhance oxygen scavenging capacity, Fe-ALD coating yields the best performance, with a high oxygen adsorption capacity of 126.8 mL/g. ALD deposition of Fe represents a versatile method to introduce Fe-based oxygen scavengers onto different supports, and it can facilitate the integration of scavengers with different types of packaging, as the deposition can be performed at a low temperature of 150 °C.

9.
Materials (Basel) ; 16(5)2023 Mar 02.
Artigo em Inglês | MEDLINE | ID: mdl-36903185

RESUMO

The super enhancement of silicon band edge luminescence when co-implanted with boron and carbon is reported. The role of boron in the band edge emissions in silicon was investigated by deliberately introducing defects into the lattice structures. We aimed to increase the light emission intensity from silicon by boron implantation, leading to the formation of dislocation loops between the lattice structures. The silicon samples were doped with a high concentration of carbon before boron implantation and then annealed at a high temperature to activate the dopants into substitutional lattice sites. Photoluminescence (PL) measurements were performed to observe the emissions at the near-infrared region. The temperatures were varied from 10 K to 100 K to study the effect of temperature on the peak luminescence intensity. Two main peaks could be seen at ~1112 and 1170 nm by observing the PL spectra. The intensities shown by both peaks in the samples incorporated with boron are significantly higher than those in pristine silicon samples, and the highest intensity in the former was 600 times greater than that in the latter. Transmission electron microscopy (TEM) was used to study the structure of post-implant and post-anneal silicon sample. The dislocation loops were observed in the sample. Through a technique compatible with mature silicon processing technology, the results of this study will greatly contribute to the development of all Si-based photonic systems and quantum technologies.

10.
Bioresour Technol ; 369: 128380, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36427768

RESUMO

Lignocellulosic and algal biomasses are known to be vital feedstocks to establish a green hydrogen supply chain toward achieving a carbon-neutral society. However, one of the most pressing issues to be addressed is the low digestibility of these biomasses in biorefinery processes, such as dark fermentation, to produce green hydrogen. To date, various pretreatment approaches, such as physical, chemical, and biological methods, have been examined to enhance feedstock digestibility. However, neither systematic reviews of pretreatment to promote biohydrogen production in dark fermentation nor economic feasibility analyses have been conducted. Thus, this study offers a comprehensive review of current biomass pretreatment methods to promote biohydrogen production in dark fermentation. In addition, this review has provided comparative analyses of the technological and economic feasibility of existing pretreatment techniques and discussed the prospects of the pretreatments from the standpoint of carbon neutrality and circular economy.


Assuntos
Hidrogênio , Lignina , Biomassa , Fermentação , Plantas , Biocombustíveis
11.
Membranes (Basel) ; 13(1)2022 Dec 25.
Artigo em Inglês | MEDLINE | ID: mdl-36676834

RESUMO

To secure existing water resources is one of the imposing challenges to attain sustainability and ecofriendly world. Subsequently, several advanced technologies have been developed for water treatment. The most successful methodology considered so far is the development of water filtration membranes for desalination, ion permeation, and microbes handling. Various types of membranes have been industrialized including nanofiltration, microfiltration, reverse osmosis, and ultrafiltration membranes. Among polymeric nanocomposites, nanocarbon (fullerene, graphene, and carbon nanotubes)-reinforced nanomaterials have gained research attention owing to notable properties/applications. Here, fullerene has gained important stance amid carbonaceous nanofillers due to zero dimensionality, high surface areas, and exceptional physical properties such as optical, electrical, thermal, mechanical, and other characteristics. Accordingly, a very important application of polymer/fullerene C60 nanocomposites has been observed in the membrane sector. This review is basically focused on talented applications of polymer/fullerene nanocomposite membranes in water treatment. The polymer/fullerene nanostructures bring about numerous revolutions in the field of high-performance membranes because of better permeation, water flux, selectivity, and separation performance. The purpose of this pioneering review is to highlight and summarize current advances in the field of water purification/treatment using polymer and fullerene-based nanocomposite membranes. Particular emphasis is placed on the development of fullerene embedded into a variety of polymer membranes (Nafion, polysulfone, polyamide, polystyrene, etc.) and effects on the enhanced properties and performance of the resulting water treatment membranes. Polymer/fullerene nanocomposite membranes have been developed using solution casting, phase inversion, electrospinning, solid phase synthesis, and other facile methods. The structural diversity of polymer/fullerene nanocomposites facilitates membrane separation processes, especially for valuable or toxic metal ions, salts, and microorganisms. Current challenges and opportunities for future research have also been discussed. Future research on these innovative membrane materials may overwhelm design and performance-related challenging factors.

12.
Front Chem ; 10: 1027024, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36339048

RESUMO

Nickel-cobalt sulfide (NiCo2S4) is a prominent member of bimetallic transition metal sulfides. It is being widely used for a variety of applications such as electrode material, photocatalysis, and energy storage devices (like pseudo capacitors, supercapacitors, solar cells, and fuel cells) due to its better electronic conductivity, manageable morphology, and high capacitance. This work presents the one-step solventless synthesis of NiCo2S4 sheet-like nanostructures and then explores their metallic nature. Scanning electron microscopy (SEM) and transmission electron microscopic (TEM) analysis show the sheet-like grown morphology. Few nanorods are also seen. Except for a recent study (Xia et al. 2015) that shows metallic behavior, most of the reports show that NiCo2S4 is a semiconductor with claimed bandgap between 1.21 and 2.4 eV. In this study, we observe from UV-Vis and diffuse reflectance spectroscopy (DRS) that NiCo2S4 has a specific band gap value between 2.02 and 2.17 eV. However, IV characteristics in the temperature range of 300-400 K show that NiCo2S4 is a metal with a positive temperature coefficient of resistance consistent with a recent report. Furthermore, we see the ohmic conduction mechanism. The Arrhenius plot is drawn, and the activation energy is calculated to be 3.45 meV. The metallic nature is attributed to the coupling of two metal species (nickel and cobalt), which accounts for its superior conductivity and performance in a variety of essential applications.

13.
ACS Mater Au ; 2(3): 215-236, 2022 May 11.
Artigo em Inglês | MEDLINE | ID: mdl-36855381

RESUMO

With the progress in the development of perovskite solar cells, increased efforts have been devoted to enhancing their stability. With more devices being able to survive harsher stability testing conditions, such as damp heat or outdoor testing, there is increased interest in encapsulation techniques suitable for this type of tests, since both device architecture compatible with increased stability and effective encapsulation are necessary for those testing conditions. A variety of encapsulation techniques and materials have been reported to date for devices with different architectures and tested under different conditions. In this Perspective, we will discuss important factors affecting the encapsulation effectiveness and focus on the devices, which have been subjected to outdoor testing or damp heat testing. In addition to encapsulation requirements for these testing conditions, we will also discuss device requirements. Finally, we discuss possible methods for accelerating the testing of encapsulation and device stability and discuss the future outlook and important issues, which need to be addressed for further advancement of the stability of perovskite solar cells.

14.
Appl Radiat Isot ; 169: 109461, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-33378724

RESUMO

Zinc oxide (ZnO) nanowires play a pivotal role in the nanoworld due to their broad range of characteristics and applications. In this work, structural and optical properties of ZnO nanowires grown on indium doped tin oxide (ITO) coated glass have been modified by copper (Cu++) ions irradiation at constant energy of 0.7 MeV. The X-ray diffraction (XRD), photoluminescence (PL), and field emission scanning electron microscope (FESEM) are used to examine changes in the nanowires. XRD results show that the crystallite size first decreases and then increases with high ion dose while peaks' intensity decreases continuously with increasing the dose. The absence of (102) plane after irradiation depicts the defects formation. FESEM clearly shows the damage that occurred in the density of nanowires and also depicts the reduced charging effect with increasing dose. The PL spectra indicate the strong near-band edge peak and green luminescence enhancement has been recorded due to low dose ion irradiation.

15.
Chemosphere ; 257: 127187, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32505038

RESUMO

Polycyclic aromatic hydrocarbons (PAHs) in ambient particulate matter contribute considerably to human health risk. Simultaneous sampling of ambient PM2.5/PM10 was done to analyze the Æ©16PAH across the four seasons of 2017 in Islamabad, Pakistan. The average Æ©16PAH concentrations in PM2.5 and PM10 were 25.69 and 40.69 ng m-3, respectively. For both PM2.5 and PM10, the highest PAHs concentration was in winter (45.14, 67.10 ng m-3), while the lowest was in summer (16.40, 28.18 ng m-3). Source appointment indicated that vehicular exhaust, i.e., diesel, gasoline and alternatively fuel liquid natural gas (LNG), and compressed natural gas (CNG) combustion was the primary PAHs contributor, whereas biomass burning and fuel combustion (coal, biomass, wood, CNG) from stationary sources were another important sources. Health risk assessment showed that the lifetime cancer risk (LCR) values of PAHs were higher than the acceptable level in all four seasons. LCR values were the highest in winter (9.23 × 10-4 for PAHs in PM2.5 and 13.98 × 10-4 for PAHs in PM10) which were 9 and 13 times higher than tolerable cancer risk level respectively, and they were 2-3 times higher than the acceptable values in other seasons.


Assuntos
Poluentes Atmosféricos/análise , Monitoramento Ambiental , Material Particulado/análise , Hidrocarbonetos Policíclicos Aromáticos/análise , Biomassa , Carvão Mineral/análise , Gasolina , Humanos , Gás Natural , Paquistão , Medição de Risco , Estações do Ano , Emissões de Veículos/análise
16.
J Air Waste Manag Assoc ; 70(12): 1340-1355, 2020 12.
Artigo em Inglês | MEDLINE | ID: mdl-32841106

RESUMO

Monsoon plays a determinant role in defining the air quality of many Asian countries. Filter-based 24 h ambient PM10 and PM2.5 sampling was performed by using two paralleled medium volume air samplers during pre-and post-monsoon periods. A negligible change in PM2.5 mass concentration from 45.77 to 44.46 µg/m3 compared to PM10 from 74.34 to 142.49 µg/m3 was observed after the monsoon season. The air quality index (AQI) results showed that the air quality of the city retained from good to slightly polluted in both periods, where PM2.5 remained as the main detrimental to air quality in 95% of the total days. The NOAA HYSPLIT model analysis and wind rose patterns showed air trajectories, especially in post-monsoon originated from relatively polluted areas transported higher PM10. Meteorological attributes indicated a more conducive atmospheric condition for secondary pollution in the pre-monsoon. Evidence showed post-monsoon as a more polluted period, compared to the pre-monsoon and would pose an extra 1.07 × 10-3 lifetime risk to the local population. Similarly, a higher level of PM10 in the post-monsoon caused 43% more premature mortality and 41% more deaths from all-cause mortality compare to the pre-monsoon period, respectively. Implications: Pakistan is an under-developing country where pollution monitoring studies are decidedly limited. Notably, studies, concise PM2.5 and health assessment are deficient. The present study may contribute to evaluating the air quality in special events such as monsoon and can also provide scientific and technical support for subsequent air pollution research. Moreover, the results help to develop adequate prevention and pollution control strategies and offer policy suggestions for monsoon observing countries in general and in particular, in Islamabad, Pakistan. These findings provide essential arguments in favor of educating people and raising awareness about the detrimental health effects of air pollution. Improving the quality of life of people with cardiovascular and respiratory disorders requires an immediate and substantial reduction of air pollution.


Assuntos
Poluentes Atmosféricos/análise , Doenças Cardiovasculares/epidemiologia , Material Particulado/análise , Doenças Respiratórias/epidemiologia , Tempo (Meteorologia) , Poluição do Ar/análise , Cidades , Monitoramento Ambiental , Humanos , Modelos Teóricos , Paquistão/epidemiologia , Tamanho da Partícula , Medição de Risco
17.
RSC Adv ; 9(32): 18106-18114, 2019 Jun 10.
Artigo em Inglês | MEDLINE | ID: mdl-35515256

RESUMO

Development of textile materials with tailored properties by coating with nano-materials is an emerging field of research. The preparation and characterization of photoactive cotton fabric for UV protection and self-cleaning properties are reported herein. In this study, a photoactive sol comprising of a reactive blue dye, C.I. Reactive Blue 21 (RB-21), and TiO2 was prepared by using sol gel method. The TiO2 nano sol was mixed with RB-21 to extend its photocatalytic activity in the visible region of the solar spectrum. The cotton fabric was coated with the RB-21/TiO2 sol via dip-pad-dry-cure method. Surface characterization of the coated cotton fabric was performed by FTIR-ATR, UV-visible absorption, XRD and SEM studies. FTIR-ATR and UV-visible spectra confirmed stable attachment of the photoactive RB-21/TiO2 coating on the cotton fabric. SEM images and XRD pattern shown the presence of anatase TiO2 on the coated cotton fabric. UV-protection, photocatalytic performance and self-cleaning properties of the coated cotton fabric were evaluated by the UV transmittance spectra, degradation of Rhodamine B (RhB) dye and stain removal under visible light respectively. Degradation of RhB was observed in the presence of RB-21/TiO2 coated cotton when exposed to visible light. Moreover, the coated cotton fabrics displayed excellent UV protection properties.

18.
J Photochem Photobiol B ; 199: 111601, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31470270

RESUMO

Human pathogenic diseases are on the rampage in the list of debilitating diseases globally. The endless quest to salvage this menace through various therapies via innocuous agents is essential to overcome these drug-resistant pathogens. This study engaged a benign, facile, biocompatible, cost-effective and eco-friendly approach to synthesized iron oxide nanoparticles (FeO-NPs) via a composite of Psidium guavaja-Moringa oleifera (PMC) leaf extract to address six most debilitating bacterial strain in vitro as an antibacterial agent. Physicochemical analysis of PMC formed nanoparticles (PMC_NPs) was effectuated through Fourier Transform Infrared Spectroscopy (FT-IR), UV-Visible Spectroscopy, X-ray Diffraction Spectroscopy (XRD), Transmission Electron Microscopy (TEM), and Vibrating Sample Magnetometer (VSM). The PMC_NPs inhibited the growth of six human pathogens with higher activity at lower concentrations. It is noteworthy from our observations that, the bacterial strains show functional susceptibility to the PMC_NPs at lower concentrations compared to the orthodox antibacterial drugs. Photocatalytic degradation was observed with a decrease in the absorbance of Methylene blue dyes with the help of PMC_NPs apropos irradiation time under visible light irradiation. Consequently, PMC_NPs serve as an enhanced substitute for the orthodox antibacterial drugs in therapeutic biomedical field sequel to its pharmacodynamics against the bacterial strains at lower concentrations and also serves as a good component for water purification.


Assuntos
Antibacterianos/química , Nanopartículas de Magnetita/química , Moringa oleifera/química , Extratos Vegetais/química , Psidium/química , Bactérias/efeitos dos fármacos , Vias Biossintéticas , Catálise , Química Verde/métodos , Humanos , Azul de Metileno/química , Tamanho da Partícula , Processos Fotoquímicos , Propriedades de Superfície
19.
IET Nanobiotechnol ; 12(4): 405-411, 2018 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-29768221

RESUMO

Mounting-up economic losses to annual crops yield due to micronutrient deficiency, fertiliser inefficiency and increasing microbial invasions (e.g. Xanthomonas cempestri attack on tomatoes) are needed to be solved via nano-biotechnology. So keeping this in view, the authors' current study presents the new horizon in the field of nano-fertiliser with highly nutritive and preservative effect of green fabricated zinc oxide-nanostructures (ZnO-NSs) during Lycopersicum esculentum (tomato) growth dynamics. ZnO-NS prepared via green chemistry possesses highly homogenous crystalline structures well-characterised through ultraviolet and visible spectroscopy, Fourier transform infrared spectroscopy, X-ray diffraction and scanning electron microscope. The ZnO-NS average size was found as small as 18 nm having a crystallite size of 5 nm. L. esculentum were grown in different concentrations of ZnO-NS to examine the different morphological parameters includes time of seed germination, germination percentage, the number of plant leaves, the height of the plant, average number of branches, days count for flowering and fruiting time period along with fruit quantity. Promising results clearly predict that bio-fabricated ZnO-NS at optimum concentration resulted as growth booster and dramatically triggered the plant yield.


Assuntos
Química Verde/métodos , Nanopartículas Metálicas/química , Extratos Vegetais/metabolismo , Solanum lycopersicum/efeitos dos fármacos , Óxido de Zinco/farmacologia , Solanum lycopersicum/crescimento & desenvolvimento , Solanum lycopersicum/metabolismo , Tamanho da Partícula , Extratos Vegetais/química , Espectroscopia de Infravermelho com Transformada de Fourier , Óxido de Zinco/química , Óxido de Zinco/metabolismo
20.
Int J Nanomedicine ; 12: 1555-1563, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28280325

RESUMO

Gold nanoparticles (GNPs) with dimension in the range of 1-100 nm have a prominent role in a number of biomedical applications like imaging, drug delivery, and cancer therapy owing to their unique optical features and biocompatibility. In this work, we report a novel technique for the synthesis of two types of GNPs namely porous gold nanoparticles (PGNPs) and solid gold nanoparticles (SGNPs). PGNPs of size 35 nm were fabricated by reduction of gold (III) solution with lecithin followed by addition of L-ascorbic acid and tri-sodium citrate, whereas SGNPs with a dimension of 28 nm were prepared by reflux method using lecithin as a single reducing agent. Comparative studies using PGNPs (λmax 560 nm) and SGNPs (λmax 548 nm) were conducted for evaluating their use as a contrast agent. These studies reveled that in direct computed tomography scan, PGNPs exhibited brighter contrast (45 HU) than SGNPs (26 HU). To investigate the effect of PGNPs and SGNPs on the liver and kidney profile, male rabbits were intravenously injected with an equal dose of 1 mg/kg weight of PGNPs and SGNPs. The effect on biochemical parameters was evaluated 72 hours after intravenous (IV) injection including liver function profile, renal (kidney) function biomarker, random blood glucose value, and cholesterol level. During one comparison of contrast in CT scan, PGNPs showed significantly enhanced contrast in whole-rabbit and organ CT scan as compared to SGNPs 6 hours after injection. Our findings suggested that the novel PGNPs enhance CT scan image with higher efficacy as compared to SGNPs. The results showed that IV administration of synthesized PGNPs increases the levels of aspartate aminotransferase (AST), alkaline phosphate (ALP), serum creatinine, and blood glucose, whereas that of SGNPs increases the levels of AST, ALP, and blood glucose.


Assuntos
Meios de Contraste/administração & dosagem , Ouro/química , Rim/diagnóstico por imagem , Fígado/diagnóstico por imagem , Nanopartículas Metálicas/química , Tomografia Computadorizada por Raios X/métodos , Animais , Meios de Contraste/química , Ouro/administração & dosagem , Injeções Intravenosas , Rim/efeitos dos fármacos , Rim/metabolismo , Testes de Função Renal , Fígado/efeitos dos fármacos , Fígado/metabolismo , Testes de Função Hepática , Masculino , Nanopartículas Metálicas/administração & dosagem , Coelhos
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