nan Lutfullah

Optimized and validated spectrophotometric method for the determination of uranium(VI) via complexation with meloxicam

An optimized and validated spectrophotometric method has been developed for the determination of uranyl ion in the presence of other metal ions. The method is based on the chelation of uranyl ion with meloxicam via beta-diketone moiety to produce a yellow colored complex, which absorbs maximally at 398 nm. Beers law is obeyed in the concentration range of 5-60 microg/mL with apparent molar absorptivity and Sandells sensitivity of 5.02 x 10(4)L/mol/cm and 0.1 microg/cm2/0.001 absorbance unit, respectively. The method has been successfully applied for the determination of uranyl ion in synthetic mixture and soil samples. Results of analysis were statistically compared with those obtained by Currahs spectrophotometric method showing acceptable recovery and precision.

Co-precipitation synthesis and characterization of Co doped SnO2 NPs, HSA interaction via various spectroscopic techniques and their antimicrobial and photocatalytic activities

Sn1-xCoxO2 (x=0.00, 0.01, 0.03, 0.05) nanoparticles (NPs) of average size ∼30-40nm were synthesized by co-precipitation method. The interaction of Co doped SnO2 NPs with human serum albumin (HSA) and their photocatalytic and antimicrobial properties were studied. The structural analysis and morphology of Co doped SnO2 NPs were analysed via X-ray diffraction (XRD), scanning electron microscopy (SEM), energy dispersive X-ray spectroscopy (EDS), high resolution transmission electron microscopy (HRTEM) and Fourier transform infrared spectroscopy (FT-IR). Besides the structural and morphological analysis, the interaction of Co doped SnO2 NPs with HSA were studied by UV-vis, Circular dichroism (CD) and fluorescence spectroscopy. Fluorescence quenching results suggest that Co doped SnO2 NPs interact with an HSA molecule through static mechanism. CD indicates that α-helicity of HSA increases due to the interaction of Co doped SnO2 NPs. The photocatalytic activities of the NPs with increased doping concentration were evaluated through a degradation process in the presence of methylene-blue (MB) dye under UV light irradiation, which exhibited that the surface area of NPs with increased doping concentration plays a major role in improving the photocatalytic activity. The antimicrobial effect of undoped and Co-doped SnO2 NPs was determined using agar-well diffusion method and analyzed against gram-positive bacteria (Bacillus Cereus MC 2434). In our results, we have found that as the doping concentration increases into NPs, zone of inhibition increases, which could be ascribed to the production of ROS and large surface area of the NPs.

Silica-supported NiO nanocomposites prepared via a sol–gel technique and their excellent catalytic performance for one-pot multicomponent synthesis of benzodiazepine derivatives under microwave irradiation

Heterogeneous and versatile NiO–SiO2 NCs were synthesized by a sol–gel technique and used as a catalyst for the one-pot multicomponent synthesis of benzodiazepine derivatives (4a–u) from a mixture of o-phenylenediamine, aromatic aldehydes and dimedone under microwave irradiation. Tetraethyl orthosilicate (TEOS) was used as a source of SiO2 for the creation of the NiO–SiO2 NCs. This catalytic protocol has many advantages, such as simple work up, inexpensive precursors, short reaction time, high yield and high surface area. The structure and morphology of the prepared nanocatalyst was characterized by using elemental analysis, scanning electron microscopy (SEM), transmission electron microscopy (TEM), X-ray diffraction (XRD), energy-dispersive X-ray spectroscopy (EDAX) and Fourier transform infrared (FTIR) spectroscopy. 1H NMR, 13C NMR and MS analyses were performed to confirm the synthesized compounds (4a–u). Moreover, the remarkable catalytic properties of the NiO–SiO2 NCs permit easy separation of the catalyst from the reaction mixture without significant loss of catalytic activity.

Photocatalytic activity and statistical determination of ball-shaped zinc oxide NPs with methylene blue dye

ABSTRACT Ball-shaped zinc oxide nanoparticles (ZnO-BNPs) were synthesized via a chemical solution process and the obtained BNPs used in a photocatalytic degradation process against methylene blue (MB) dye showed excellent photocatalytic properties (efficiency 72.37%). The analytical parameters, such as validity, reliability, accuracy, precision, linearity, range, limit of detection (LOD), limit of quantitation (LOQ), selectivity, specificity, and stability, were applied to confirm and fix the effective concentration of BNP suspension solution, affected by MB dye. The absorption spectra of ZnO-BNPs, MB dye, and ZnO-BNPs with MB dye were recorded at a maximum absorbance of λmax 480, 650, and 690 nm, respectively.

Solid phase extraction and determination of Cr(III) by spectrophotometry using cefaclor as a complexing reagent and FAAS.

The present study reports on the application of modified groundnut shell as a new, easily prepared, and stable sorbent for the extraction of trace amount of Cr(III) in aqueous solution. 2-Hydroxybenzaldiminoglycine was immobilized on groundnut shells in alkaline medium and then used as a solid phase for the column preconcentration of Cr(III). The elution was carried out with 3xa0mL of 2xa0molu2009L−1 HCl. The amount of eluted Cr(III) was determined by spectrophotometry using cefaclor as a complexing reagent and by flame atomic absorption spectrometry (FAAS). Different experimental variables such as pH, amount of solid sorbent, volume and concentration of eluent, sample and eluent flow rate, and interference of other metal ions on the retention of Cr(III) were studied. Under the optimized conditions, the calibration curves were found to be linear over the concentration range of 13–104 and 10–75xa0μgu2009L−1 with a detection limit of 3.64 and 1.24xa0μgu2009L−1 for spectrophotometric method and FAAS, respectively. An enrichment factor of 200 and RSD of ±1.19–1.49xa0% for five successive determinations of 25xa0μgu2009L−1 were achieved. The column preconcentration was successfully applied to the analysis of tap water and underground water samples.

Nanotransition Materials (NTMs): Photocatalysis, Validated High Effective Sorbent Models Study for Organic Dye Degradation and Precise Mathematical Data’s at Standardized Level

The present work describes the synthesis of copper oxide nanoparticles (CuONPs) via a solution process with the aim of applying the nano-adsorbent for the reduction of methylene blue (MB) dye in alkaline media. These NPs were characterized via Field emission scanning electron microscopy (FE-SEM), X-ray diffraction, high-resolution Transmission electron microscopy (TEM), and ultra violet UV-visible spectroscopy to confirm their morphology and crystalline and optical properties in order to design an adsorption-degradation process. The photocatalytic CuONPs exhibited dynamic properties, great adsorption affinity during the chemisorption process, and operated at various modes with a strong interaction between the adsorbent and the adsorptive species, and equilibrium isotherm, kinetic isotherm, and thermodynamic activities in the presence of UV light. All basic quantities, such as concentration, pH, adsorbent dose, time, and temperature, were determined by an optimization process. The best-fitted adsorption Langmuir model (R2 = 0.9988) and performance, including adsorption capacity (350.87 mg/g), photocatalytic efficiency (90.74%), and degradation rate constant (Ks = 2.23 ×10−2 min−1), illustrate good feasibility with respect to sorption-reduction reactions but followed a pseudo-second-order kinetic on the adsorbent surface, reaching an equilibrium point in 80 min. The thermodynamic analysis suggests that the adsorption reaction is spontaneous and endothermic in nature. The thermodynamic parameters such as enthalpy (∆H°), entropy (∆S°), and Gibbs free energy (∆G°) give effective results to support a chemical reduction reaction at 303 K temperature. The equilibrium isotherm and kinetic and thermodynamic models with error function analysis explore the potential, acceptability, accuracy, access to adsorbents, and novelty of an unrivaled-sorption system.