22 research outputs found
A new rhodamine B based fluorometric chemodosimeter for Cu2+ ion in aqueous and cellular media
A simple, sensitive and selective fluorescent chemo dosimeter rhodamine B phenyl hydrazide (RBPH) for Cu2+ was proposed. This probe is non fluorescent and colorless but exhibits fluorescent enhancement at 580 nm and displayed color change from colorless to pink for Cu2+ in the pH range 1-6. Fluorescence microscope experimental results reveals that this chemo sensor is cell permeable and can be used for fluorescence imaging of Cu2+ ions in living cells. This probe can detect Cu2+ with good linear relationships from 10 to 100 nM with r=0.99971 then limit of detection was found to be 0.015 nM with +/- 0.91% RSD at 10 nM concentrations. 2013 Elsevier B.V. All rights reserved
Optimization and Numerical investigation of organic dye degradation using Response Surface by green synthesized ZrO2 nanoparticles and its antibacterial activity
In this work, the tetragonal Zirconium oxide (ZrO2) nanoparticles (NPs) were successfully synthesized by solution combustion method using Zirconium (IV) oxynitrate hydrate as the metal precursor and an oxidizer, Basella alba raw extract at 6000C. In this study, natural fuel is used to avoid harmful chemical fuels that may pollute the environment during combustion. The impact of the fuel-to-oxidant molar ratio on the surface morphological features of nanocrystalline zirconia particles has been documented. We investigated the Physico-chemical properties of the ZrO2 NPs via thorough characterizations like XRD, EDS, SEM, TEM, FTIR, UV-Vis, and BET. ZrO2 NPs exhibit perfect photocatalytic degradation activity towards Evans blue, a toxic dye. The influence of contact time, initial dye concentration, and pH were among the independent variables used in the study. The Response Surface Model (RSM) was used to optimize and describe the interdependencies of the different variables. The method was evaluated using the Box-Behnken design (BBD). A second-order polynomial model was used to properly understand the experimental results, and the effectiveness of the chosen model was verified by the strong agreement in determination coefficient values. ZrO2 NPs also exhibit good antibacterial activity on Gram-negative Klebsiella pneumoniae and Gram-positive bacteria, Bacillus subtilis
An efficient method for Aryl Nitro Reduction and cleavage of Azo compounds using iron powder/calcium chloride
A novel, efficient Fe/CaCl2 system is revealed for the reduction of nitroarenes and reductive cleavage of azo compounds by catalytic transfer hydrogenation (CTH). The selective reduction of nitro compounds in the presence of sensitive functional groups including halides, carbonyl, hydroxyl, aldehyde, methyl, methoxy, acetyl, nitrile, and ester substituents with an excellent yields is reported. The simple experimental procedure and easy purification make the protocol advantageous
Green-Synthesized Sm3+-Doped ZnO Nanoparticles for Multifunctional Applications
The present study focuses on the green-mediated synthesis of pristine and Sm3+-doped ZnO nanoparticles using Syzygium cumini fruit extract. The prepared material was characterized by various characterization techniques. Photocatalytic degradation of a fast orange red (FOR) dye under UV light resulted in 88% degradation, with a minimal decrease (87.90%) observed even after five successive runs, indicating the stability and effectiveness of the catalyst. The enhancement in degradation efficiency is attributed to the incorporation of Sm3+ ions into the ZnO lattice. Utilizing the optimized Sm3+ (5 mol%)-doped ZnO nanoparticles, cyclic voltammetry (CV) and electrochemical impedance spectra (EIS) were performed on the prepared electrode, demonstrating the excellent CV properties; this enhancement is attributed to the modification of ZnO’s redox chemistry and the alteration of charge transfer kinetics at the electrode-electrolyte interface due to the addition of Sm3+ into the ZnO structure. The antibacterial activity was performed against two pathogenic strains, i.e., Escherichia coli and Streptococcus aureus. The obtained results suggest that the prepared material holds great promise for catalytic, energy storage, antibacterial, and other multifunctional applications
Blackberry gel-assisted combustion modified MgO: Sm3+ nanoparticles for photocatalytic, battery, sensor and antibacterial applications
Green synthetic methods are currently preferred in industry over other physicochemical methods. Herein, we present a facile, environmentally friendly, non-toxic approach for the fabrication of MgO using jamun fruit extract. The phytochemicals present in the fruit extract, such as kaemferol, glucoside, anthocyanins, ellagic acid, myricetin, and isoquercetin, facilitate the bio-reduction of Mg(NO3)2. Pure and Sm3+ (1–7 mol %) doped MgO nanomaterials were synthesized using this bio-mediated synthetic method. The structural and morphological properties of the synthesized nanomaterials were studied using Powder X-ray diffraction (PXRD), Field Emission Scanning Electron Microscopy (FE-SEM), Energy Dispersive Spectroscopy (EDS), and Diffused Reflectance Spectroscopy (DRS) techniques. The effect of Sm3+ ions on the host matrix for the photo-catalytic oxidation of Fast Orange-Red (FOR) dye was investigated under UV light irradiation. MgO: Sm3+(3 mol %) exhibited superior (94 %) degradation of the dye compared to pristine and other doped catalysts, attributed to the maximum migration of charge carriers at the catalyst's surface. Additionally, the 3 mol % Sm3+ doped MgO electrode demonstrated a smaller charge transfer resistance, indicating superior capacitive properties compared to pristine and other doped electrodes. The synthesized materials also exhibited effective bacterial activity against pathogens. This research demonstrates the potential of the synthesized nanomaterials for environmental pollution purification, as well as their utility as electrode materials for supercapacitors, batteries, sensors, and antibacterial applications
Comparison of the photocatalytic degradation of trypan blue by undoped and silver-doped zinc oxide nanoparticles
Zinc oxide (ZnO) and silver doped zinc oxide (ZnO:Ag) nanoparticles were prepared using nitrates of zinc and silver as oxidizers and ethylene diaminetetraacetic acid (EDTA) as a fuel via low-temperature combustion synthesis (LCS) at 500 degrees C. X-ray diffraction (XRD) pattern indicates the presence of silver in the hexagonal wurtzite structure of ZnO. Fourier transform infrared (FTIR) spectrum indicates the presence of Ag-Zn-O stretching vibration at 510 cm(-1). Transmission electron microscopy (TEM) images shows that the average particle size of ZnO and ZnO:Ag nanoparticles were found to be 58 nm and 52 nm, respectively. X-ray photoelectron spectroscopy (XPS) data clearly indicates the presence of Ag in ZnO crystal lattice. The above characterization techniques indicate that the incorporation of silver affects the structural and optical properties of ZnO nanoparticles. ZnO:Ag nanoparticles exhibited 3% higher photocatalytic efficiency than pure ZnO nanoparticles. ZnO:Ag nanoparticles show better photocatalytic activity for the degradation of trypan blue (TrB) compared to undoped ZnO nanoparticles. (C) 2014 Elsevier Ltd. All rights reserved
Three-Dimensional Framework for Artificial Photosystems
A c c e p t e d M a n u s c r i p t 1 Highlights • Lyotropic liquid crystals are unique media via reagent diffusion-partition. • Structure and orientation as well as dopant nature are significant. • First report of liquid nanotechnology for biomimetic artificial photosystems. Page 2 of 35 A c c e p t e d M a n u s c r i p t A c c e p t e d M a n u s c r i p t 3 Abstract Normal lyotropic liquid crystals (in the lamellar or hexagonal phases) are investigated as a route to afford a structured, three-dimensional, quasi-biphasic framework within which electron transfer cascades may take place using cyclic voltammetry. For model systems, we show that these can take place through reagent partitioning between the hydrophobic and hydrophilic subphases, and illustrate how the structure and its orientation, the nature of the ionic doping of the framework, and the hydrophobicity of the redox analyte may give rise to changes in the observed voltammetric waveshape. For the case of an artitifical mimic of the first few stages of Photosystem I, we demonstrate that photoinduced electron transfer is likewise affected by the orientation, and develop a system of photon efficiency of ~0.1%