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Santiniketan, India

Mondal P.,Vivekananda Mahavidhyalaya | Bayen S.P.,Vivekananda Mahavidhyalaya | Roy K.,Vivekananda Mahavidhyalaya | Chowdhury P.,Synthetic Polymer Laboratory
Separation Science and Technology (Philadelphia) | Year: 2012

Immobilization of 4-vinyl pyridine (4-VP) onto silica gel (SG) and its coordination with cupric ion (SG-4-VP→Cu 2+) leading to a new solid phase extractor has been carried out by a simple chemical technique. Immobilization and coordination reactions are characterized by chemical, FTIR, UV, and thermo-gravimetric analysis. The role of cupric ion on Cr(VI) binding capacity of the synthesized organic-inorganic hybrid material has been elucidated. The silica gel immobilized 4-VP/Cu 2+ complex (hybrid material) is tested for selective extraction and pre-concentration of Cr(VI) from aqueous solution. The Cr(VI) binding behavior of the synthesized material is studied at different pH, time, and temperature of the medium in both competitive and non-competitive conditions. © 2012 Copyright Taylor and Francis Group, LLC.

Jayaramudu T.,Korea Advanced Institute of Science and Technology | Raghavendra G.M.,Korea Advanced Institute of Science and Technology | Raju K.M.,Synthetic Polymer Laboratory | Sadiku E.R.,University of South Africa | Kim J.,Center for Nano Cellulose Future Composites
Journal of Applied Polymer Science | Year: 2016

For the first time, green-tea (GT)-based magnetic nanohydrogels were developed for drug-delivery purposes. The hydrogel matrices were fabricated via the in situ polymerization of acrylamide with GT molecules. Magnetic nanoparticles were synthesized by the reduction of the 1:2 molar ratio mixture of ferrous sulfate heptahydrate and ferric chloride hexahydrate with an ammonia solution. A chemotherapeutic drug, 5-fluorouracil, was chosen as a model drug, and its releasing profiles in the presence and absence of the external magnetic field were evaluated at a pH of 7.4. We observed that in the presence of the applied magnetic field, these magnetic nanohydrogels released 2.86% more drug than in the absence of a magnetic field. The magnetic nanohydrogels were characterized by X-ray diffraction, Fourier transform infrared spectroscopy, scanning electron microscopy, vibrating sample magnetometry, and transmission electron microscopy. © 2016 Wiley Periodicals, Inc.

Roy K.,Synthetic Polymer Laboratory | Mondal P.,Vivekananda Mahavidyalaya | Bayen S.P.,Synthetic Polymer Laboratory | Chowdhury P.,Synthetic Polymer Laboratory
Journal of Macromolecular Science, Part A: Pure and Applied Chemistry | Year: 2012

Polypyrrole salt of desired structure has been synthesized sonochemically and characterized by chemical, spectral and thermal analysis. Surface morphology of the polymer is examined by scanning electron microscope (SEM). Chromium(VI) sorption-desorption properties of the polymer has been studied through optimization of pH, contact time and temperature. Selectivity towards Cr(VI) sorption in the presence of competitive ions has been tested. The relevant kinetic parameters are evaluated to elucidate the sorption-desorption mechanism. The metal binding capacity of the polymer is compared with the commercially available ion-exchangers. Copyright © Taylor and Francis Group, LLC.

Bayen S.P.,Synthetic Polymer Laboratory | Chowdhury P.,Synthetic Polymer Laboratory
Journal of Environmental Chemical Engineering | Year: 2015

Thioacetamide (TAA), a well known ligand having both S and N donors, has been immobilized quantitatively onto silica gel (SG) surface for easy detection (through naked eye) and removal of mercury (Hg) from environmental samples for the first time. The quantitative immobilization involves direct incorporation of TAA onto SG without widely used Mannich reaction. TAA immobilized SG (TAA@FSG) has been characterized by spectral, morphological, elemental, thermal, chemical and electrochemical analysis. The TAA@FSG has a BET surface area of 243.31 m2 g-1 with an average pore diameter of 3-7 nm. The degree of immobilization (α = ∼9.45 μmol m-2) is quantitative. The role of TAA in detecting and removing Hg has been elucidated. Trace level of Hg (below 0.01 mg L-1) has been detected through naked eye. The Hg2+ binding capacity of the synthesized material is found to be 17.5 mg g-1 even at very low level of Hg (Co = 100 mg L-1). The developed method may be used to remove Hg from real samples. © 2014 Elsevier Ltd. All rights reserved.

Bayen S.P.,Synthetic Polymer Laboratory | Chowdhury P.,Synthetic Polymer Laboratory
Desalination and Water Treatment | Year: 2014

Aniline moiety was immobilized on the surface of silica gel (SG) through functionalizing the later by 3-chloropropyl trimethoxysilane (3-CPTS). The aniline immobilization was confirmed by chemical, Fourier transform infrared (FTIR), thermo gravimetric analysis (TGA), and scanning electron microscopy (SEM). Solid phase extraction (SPE) property of the synthesized product was studied in terms of Cr(III) uptake by batch and column methods. Metal ion adsorption and its isotherm, kinetic and thermodynamic parameters were evaluated. The mechanistic path involved in up taking metal ion has been suggested. The Cr(III) binding capacity was found to be 8.7 mg g-1 at trace level of chromium in aqueous medium. The presence of chloride ion improved the metal ion binding capacity as well as selectivity to a significant extent. The developed material and the selective extraction method were tested by applying it in real samples and the results were compared with the reported values. © 2013 © 2013 Balaban Desalination Publications. All rights reserved.

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