Novel chromium imprinted polymer: synthesis,characterization and analytical applicability for the selective remediation of Cr(VI) from an aqueous system

In this study, we report the synthesis of chromium imprinted polymer (Cr-IP) by a simple and facile one-pot precipitation polymerization technique by using 1-vinyl imidazole as ligand and methacrylic acid as functional monomer and their application for the specific removal of toxic hexavalent chromium from aqueous media. To attain maximum adsorption capacity various components i.e. functional monomer, cross-linker, and the molar ratio of ligand, monomer, and cross-linker were evaluate. Furthermore, several parameters i.e. pH, adsorbent dose, agitation time and shaking speed were also optimized to obtained maximum adsorption efficiency. The synthesized Cr-IP was characterized by SEM, EDX and FT-IR. The kinetic data were well described by pseudo-second-order while Langmuir model is best fitted to isotherm data. The maximum adsorption capacity of Cr-IP was 76.92mg/g. The relative standard deviation, limit of detection and quantification of this method was found to be 4.7%, 0.71µg/L and 2.36µg/L. The relative selective coefficient of Cr(VI) ions and competitive ions is greater than one due to the imprinting effect. This Cr-IP polymer also possesses good reproducibility and stability. The synthesized imprinted polymer has successfully applied for elimination of toxic Cr(VI) from real water samples.     

A review on synthetic approaches of heterocycles via insertion-cyclization reaction

Abstract

Heterocyclic compounds have a wide range of applications: they are predominant among the type of compounds used as pharmaceuticals, agrochemicals, fine chemicals, electronic components, polymers, and veterinary products. There is a vast scope to develop new heterocyclic compounds considering the high yield, low waste, and green synthesis. In this review, we have described the synthesis of heterocycles via insertion and cyclization which is achieved in recent years with the ideas, challenges, and milestone reactions.     

Development of a new chromogenic spray reagent for the detection and identification of synthetic pesticide carbaryl in biological material by high-performance thin-layer chromatography

JPC – Journal of Planar Chromatography – Modern TLC -     

Investigation of CdS and CdTe thin films and influence of CdCl2 on CdTe/CdS structure

CdTe/CdS heterojunction solar cell structure has been fabricated using simple, easy and low-cost methods. To fabricate this structure, CdS and CdTe thin films are deposited onto FTO-coated conducting glass substrates by chemical bath deposition (CBD) and electrodeposition method, respectively. The optimized growth conditions are chosen for both CdS and CdTe films by investigating the optical, structural and morphological properties of both the as-deposited and annealed films. Optical measurement showed that CdS films have higher transmittance and lower absorbance, and CdTe films have lower transmittance and higher absorbance in the near infrared region. The band gap of CdS films is estimated to lie in the range 2.29–2.41 eV and that of CdTe films is in the range 1.53–1.55 eV. X-ray diffraction (XRD) study reveals that CdS and CdTe films are polycrystalline with preferential orientation of (1 1 1) plane. Scanning electron microscopy (SEM) study reveals that both films are smooth, void-free and uniformly distributed over the surface of the substrate. Fabricated CdTe/CdS structure showed the anticipated rectifying behaviour, and the rectifying behaviour is observed to improve due to CdCl₂ treatment.     

Fractal pattern growth simulation in electrodeposition and study of the shifting of center of mass

We presented simulation of fractal pattern in electrodeposition (Diffusion limited aggregation) using concept of off lattice walk.It is seen that the growth patterns are based on a parameter called ‘bias’. This parameter ‘bias’ controls the growth of patterns similar to that of electric field in electrodeposition technique. In present study the fractal patterns are grown for different values of ‘bias’. Dendritic patterns grown at lower value of ‘bias’ comprises open structure and show limited branching. As the bias is increased the growth tends to be dense and show more crowded branching. Box counting was implemented to calculate fractal dimension. The structural and textural complexities and are compared with the experimental observations.It was also noted that in the evolution of DLA patterns, the center of mass of the growth is shifted slightly. We tracked the position of the center of mass of simulated electro deposits under different electric field conditions. The center of mass exhibit random walk like patterns and it wanders around the origin or the starting point of the growth.     

Stability‐indicating ultra‐performance liquid chromatography method for the estimation of thymoquinone and its application in biopharmaceutical studies

Thymoquinone (THQ) is known for its neuroprotective and anti‐convulsant properties in preclinical studies. We herewith describe a simple, rapid, selective, sensitive and stability‐indicating UPLC method for the estimation of THQ and its application to biopharmaceutical studies such as in vitro release from nanoparticulate system and in vivo pharmacokinetic study. The method employed gradient elution using a Waters Acquity HSS‐T3 C₁₈ (100 × 2.1 mm, 1.8 µm) UPLC column. The mobile phase consisted of water and acetonitrile, pumped at a flow rate of 0.5 mL/min. The injection volume was 5 µL and THQ was monitored at 294 nm wavelength with a total run time of 6 min. In solution as well as in plasma, the method was found to be linear (r ≥ 0.998), precise (CV ≤ 2.45%) and accurate (recovery ≥ 84.8%) in the selected concentration range of 0.1–0.8 µg/mL. Forced degradation studies revealed that THQ undergoes degradation under acidic, basic, oxidation and UV light stress conditions. However, the developed UPLC method could effectively resolve degradation product peaks from THQ. Further, no interference was found at the retention time of THQ from any plasma components, indicating selectivity of the developed method. For solutions, the limits of detection and quantitation of the method were found to be 0.001 and 0.0033 µg/mL, respectively; while in plasma they were 0.006 and 0.02 µg/mL, respectively. The validated method was successfully applied to quantify THQ in dissolution medium as well as oral in vivo pharmacokinetic study of THQ suspension and THQ‐ solid lipid nanoparticle (THQ‐SLN) formulation. A 2‐fold increase in the relative bioavailability was observed with the THQ‐SLN compared with THQ. The results indicate that the SLN significantly increased plasma concentrations and retention within the systemic circulation. Copyright © 2010 John Wiley & Sons, Ltd.     

Synthesis of crystalline umangite phase of copper selenide (Cu3Se2) for TiO2 photoanode-based solar cell application

Journal of Solid State Electrochemistry - This study deals with the sensitization of the porous titanium oxide (TiO2) films deposited on fluorine doped tin oxide with copper selenide (Cu3Se2). The...