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The present study is focused on the synthesis of silver nano particles (Ag NPs) using an aqueous extract of the whole plant of Sida cordifolia as a potential bio-reducing agent and assessment of their antibacterial activity. UV-Vis spectroscopy of composed silver colloidal solution displayed surface Plasmon resonance peak at 420â¯nm. XRD and TEM analysis revealed the morphology as ultra-small, monodispersed spherical nanoparticles with face-centered cubic structure and mean particle size of 3-6â¯nm. This ultra-small nano size might owe to the slow reaction time and phytochemicals existing in the S. cordifolia extract. The Ag NPs are trailed for antibacterial activity against 5 fish (Aeromonas hydrophila, Pseudomonas fluorescence, Flavobacterium branchiophilum, Edwardsiella tarda and Yersinia rukeri) and 4 human (Escherichia coli, Klebsiella pneumonia, Bacillus subtilis and Staphyloccocus aureus) bacterial pathogens. In all the cases, Ag NPs from Sida cordifolia plant extract manifested noteworthy antibacterial effects on par with positive control i.e.; Gentamicin.
Assuntos
Anti-Infecciosos/metabolismo , Anti-Infecciosos/farmacologia , Bactérias/efeitos dos fármacos , Nanopartículas Metálicas , Sida (Planta)/metabolismo , Prata/metabolismo , Prata/farmacologia , Química Verde/métodos , Microscopia Eletrônica de Transmissão , Extratos Vegetais/metabolismo , Análise Espectral , Difração de Raios XRESUMO
Lead-based halide perovskites have gained significant prominence in recent years in optoelectronics and photovoltaics, owing to their exceptional optoelectronic properties. Nonetheless, the toxicity of lead (Pb) and the stability concern pose obstacles to their potential for future large-scale market development. Herein, stable lead-free Cs3Bi2I9 (CBI) films are presented with smooth and compact morphologies synthesized via chemical vapor deposition (CVD), demonstrating their application as an UV photodetector in a self-powered way. The self-powered photodetectors (SPDs) exhibit remarkable characteristics, including a responsivity of 1.57 A W-1 and an impressive specific detectivity of 3.38 × 1013 Jones under the illumination of 365 nm at zero bias. Furthermore, the SPDs exhibit a nominal decline (≈2.2%) in the photocurrent under constant illumination over 500 h, highlighting its impressive long-term operational stability. Finally, the real-time UV-detection capability of the device is demonstrated by measuring the photocurrent under various conditions, including room light and sunlight at different times. These findings offer a new platform for synthesizing stable and high-quality perovskite films, and SPDs for advancing the development of wearable and portable electronics.
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Liposomes are well-recognized and essential nano-sized drug delivery systems. Liposomes are phospholipid vesicles comprised of cell membrane components and have been employed as artificial cell models to mimic structure and functions of cells and are of immense use in various biological analyses. Liposomes acquire great advantages and provide wide range of applications as useful drug carriers in pre-clinical and clinical trials. This review summarizes exclusively on scalable techniques for liposome preparation and focuses on the strengths and limitations with respect to industrial applicability. Also, this review discusses the updated recent advancements in biomedical applications with a mention of key highlights of commercially available formulations, clinical trials and patents in recent past. Furthermore, this review also provides brief information of the classification, composition and characterization of liposomes.
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The direct synthesis of inherently defect-free, large-area graphene on flexible substrates is a key technology for soft electronic devices. In the present work, in situ plasma-assisted thermal chemical vapor deposition is implemented in order to synthesize 4 in. diameter high-quality graphene directly on 10 nm thick Ti-buffered substrates at 100 °C. The in situ synthesized monolayer graphene displays outstanding stretching properties coupled with low sheet resistance. Further improved mechanical and electronic performances are achieved by the in situ multi-stacking of graphene. The four-layered graphene multi-stack is shown to display an ultralow resistance of ≈6 Ω sq-1, which is consistently maintained during the harsh repeat stretching tests and is assisted by self-p-doping under ambient conditions. Graphene-field effect transistors fabricated on polydimethylsiloxane substrates reveal an unprecedented hole mobility of ≈21â¯000 cm2 V-1 s-1 at a gate voltage of -4 V, irrespective of the channel length, which is consistently maintained during the repeat stretching test of 5000 cycles at 140% parallel strain.
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Zinc Oxide (ZnO) is currently used in nano-cosmeceuticals and nano-pharmaceuticals topically due to their multifunctional efficiency irrespective of the synthetic method. Bio-reducers are cosmopolitically famed to attain stable, reliable, and toxic free synthesis. Thus, the objective of the current study is to prepare ZnO NPs in a greener approach using Annona squamosa (AS) leaf extract and to evaluate their antibiotic potentiation capacity and anticancer activity. The novel synthetic process of ZnO NPs was performed without using any chemicals (reducing or stabilizing agents) or high temperature processing under continuous stirring and refluxion in the presence of oxygen environment. AS have renowned phytochemicals with medicinal properties. Therefore, the mounting of secondary metabolites onto ZnO NPs during synthesis as reducing, stabilizing, capping agents may impart additional biomedical efficacy. The ZnO NPs were prepared with the assessment of stabilization (characteristic peak at 375â¯nm) from absorbance spectra. Further, SEM, TEM, XRD, FTIR, and Raman analysis of AS-ZnO NPs were performed to elucidate the size, shape, nature, chemical structure and composition. The characterization techniques revealed particles of 20-50â¯nm size, hexagonal shaped crystalline structure with diverse phytochemicals and functional groups. In addition, AS-ZnO NPs were investigated for antibacterial activity along with antibiotic potentiating capability through combinational assay. Furthermore, the anticancer potential of AS-ZnO NPs was evaluated against HeLa cell line along with assessment of biocompatibility on HEK-293 cell line using MTT assay. Based on the findings, our study exploits green-synthesized ZnO NPs as an effective strategy for potentiation of antibiotic activity and anticancer activity in a biocompatible perspective.
Assuntos
Annona/química , Antibacterianos/farmacologia , Antineoplásicos/farmacologia , Nanopartículas Metálicas/química , Óxido de Zinco/farmacologia , Antibacterianos/química , Sobrevivência Celular/efeitos dos fármacos , Avaliação Pré-Clínica de Medicamentos , Sinergismo Farmacológico , Química Verde , Células HEK293 , Células HeLa , Humanos , Nanopartículas Metálicas/uso terapêutico , Testes de Sensibilidade Microbiana , Extratos Vegetais/química , Folhas de Planta/química , Espectroscopia de Infravermelho com Transformada de Fourier , Temperatura , Difração de Raios X , Óxido de Zinco/químicaRESUMO
The aim of the work is to synthesize iron oxide (α-Fe2O3) nanoparticles using Sida cordifolia plant extract along with evaluation of its antibacterial activity. The presence of phytochemicals in Sida cordifolia methanolic plant extract was investigated by HPTLC and LC-MS/TOF. The probable mechanism for formation of α-Fe2O3 nanoparticles in mediation with plant extract was demonstrated. The green synthesized iron oxide nanoparticles (α-Fe2O3 NPs) were characterized by using X-ray diffraction, scanning, and transmission electronic microscopy, TG-DTA, FTIR, and UV spectroscopy. The crystallite size of prepared α-Fe2O3 nanoparticles estimated via Debye-Scherrer formula and Williamson-Hall plot was around 20 nm which is in accordance with particle size in TEM images. The S. cordifolia mediated iron-oxide nanoparticles (α-Fe2O3 NPs) hold potent antibacterial activity against various gram positive and gram negative bacteria.
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Since the discovery and subsequent widespread use of antibiotics, a variety of bacterial species of human and animal origin have developed numerous mechanisms that render bacteria resistant to some, and in certain cases to nearly all antibiotics, thereby limiting the treatment options and compromising effective therapy. In the present study, the green synthesis of nanoparticles is carried out by the reduction of silver acetate in the presence of crude methanolic root extracts of Diospyros paniculata, a member of family Ebenaceae. The UV-Vis absorption spectrum of the biologically reduced reaction mixture showed the surface plasmon peak at 428 nm, a characteristic peak of silver nanoparticles. X-ray diffraction (XRD) analysis confirmed the face-centered cubic crystalline structure of metallic silver. The average diameter of Ag NPs is about 17 nm from Transmission Electron Microscopy (TEM) which is in good agreement with the average crystallite size (19 nm) calculated from XRD analysis. Further the study has been extended to the antimicrobial activity against test pathogenic Gram (+), Gram (-) bacterial and fungal strains. The biologically synthesized silver nanoparticles showed promising activity against all the tested pathogenic strains and the activity has been enhanced with the increased dose levels.