Maqsood Malik

Publications

• Microemulsion method: A novel route to synthesize organic and inorganic nanomaterials

  Maqsood Ahmad Malik, M. Y. Wani, M. A. Hashim

  Arabian journal of chemistry. 01/2011;

• Nanotoxicity: Dimensional and Morphological Concerns

  M. Y. Wani, M. A. Hashim, F. Nabi, Maqsood Ahmad Malik

  Advances in Physical Chemistry. 01/2011;

• Micelles-assisted MnO4- oxidation of isoleucine. A kinetic study

  Maqsood Ahmad Malik, R. A. Sheikh, S. A. AL-Thabaiti, A. Y. Obaid, Z. Khan

  Journal of dispersion science and technology (Ms JDST 2011/102). 01/2011;

• Ionic Liquids in Supported Liquid Membrane Technology

  Maqsood Ahmad Malik, M. A. Hashim, F. Nabi

  Chemical Engineering journal. 01/2011;

• Extraction of metal ions by ELM Separation Technology

  Maqsood Ahmad Malik, M. A. Hashim, F. Nabi

  Journal of dispersion science and technology. 01/2011;

• DFT Calculations of Vibrational Frequencies of Aluminum and Phosphorous Doped-carbon Clusters

  F. Nabi, Maqsood Ahmad Malik, C. G. Jesudason

  Arabian Journal for science and engineering. 01/2011;

• Experimental and Predicted Viscosities of Binary Mixtures of Styrene with m,o, or p-xylene and Toluene at Different Temperatures

  F. Nabi, Maqsood Ahmad Malik, C. G. Jesudason

  Asian Journal of Chemistry. 01/2011; 23.

• Micellar and salt kinetic effects upon the reaction MnO4- + EDTA

  Maqsood Ahmad Malik, S. A. Al-Thabaiti, A. O. Al-Youbi, Z. Khan

  Journal of Saudi chemical society. 01/2011;

• Kinetics of silver nanoparticle growth in aqueous polymer solutions

  Z. Khan, S. A. Al-Thabaiti, F.M. Al- Nowaiser, A. Y. Obaid, A. O. Al-Youbi, Maqsood Ahmad Malik

  Arabian journal of chemistry. 01/2011;

• Anti-corrosion Ability of Surfactants: A Review

  Maqsood Ahmad Malik, M.A. Hashim, F. Nabi, S.A. AL-Thabaiti, Z. Khan

  International journal of electrochemical science. 01/2011;

• Effect of cetyltrimethylammonium bromide on the oxidation of phthalic acid by MnO4- in aqueous medium

  N. Ahmad, Maqsood Ahmad Malik, S.A. Al-Thabaiti, A.Y. Obaid, Z. Khan

  Journal of dispersion science and technology. 01/2011;
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  Preparation of silver nanoparticles using tryptophan and its formation mechanism.

  Zoya Zaheer, Maqsood Ahmad Malik, F M Al-Nowaiser, Zaheer Khan

  Colloids and surfaces. B, Biointerfaces. 12/2010; 81(2):587-92.

  A non-toxic route was used for the preparation of silver nanoparticles using tryptophan (Trp) as reducing/stabilizing agent in the presence of cetyltrimethyl ammonium bromide (CTAB). Role of water soluble neutral polymer poly(vinylpyrrolidone) (PVP) has been studied on the growth of yellow colour si... [more] A non-toxic route was used for the preparation of silver nanoparticles using tryptophan (Trp) as reducing/stabilizing agent in the presence of cetyltrimethyl ammonium bromide (CTAB). Role of water soluble neutral polymer poly(vinylpyrrolidone) (PVP) has been studied on the growth of yellow colour silver nanoparticle formation. The synthesized nanostructures were characterized by UV-Visible absorption spectroscopy, transmission electron microscopy (TEM) by observing the size and distribution of silver nanoparticles. As the reaction proceeded, particles grew up to about 10 and 20 nm in the presence and absence of PVP, respectively, as determined by TEM. The formed nanoparticles showed the highest absorption plasmon band at 425 nm. Rate of silver sol formation increases with the [Trp], [CTAB] and [PVP], reaching a limiting value and then decreases with the increase in concentrations of these reagents. It was observed that nanoparticles are spherical, aggregated and poly dispersed in the absence and presence of PVP, respectively. On the basis of kinetic data, a suitable mechanism is proposed and discussed for the silver sol formation.
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  A kinetic study of silver nanoparticles formation from paracetamol and silver(I) in aqueous and micellar media.

  Naushad Ahmad, Maqsood Ahmad Malik, F M Al-Nowaiser, Zaheer Khan

  Colloids and surfaces. B, Biointerfaces. 02/2010; 78(1):109-14.

  UV-vis spectrophotometeric, transmission electron microscopy (TEM) and viscometric techniques were used for the formation, characterization and kinetics of silver sol formation using silver nitrate as source of silver, paracetamol as reducing agent and cetyltrimethylammonium bromide (CTAB) as the st... [more] UV-vis spectrophotometeric, transmission electron microscopy (TEM) and viscometric techniques were used for the formation, characterization and kinetics of silver sol formation using silver nitrate as source of silver, paracetamol as reducing agent and cetyltrimethylammonium bromide (CTAB) as the stabilizer in absence and presence of poly(vinyl alcohol) (PVA). The sigmoidal curve of absorbance versus the reaction time suggests an autocatalytic reaction path. Transmission electron microscopy (TEM) results show that the silver nanoparticles are all spherical, highly dispersed and aggregated in aqueous solution. In the formation of silver nanoparticles, alkaline solution is required. The presence of PVA inhibits the rate of silver nanoparticles formation. Effects of [Ag(+)], [paracetamol], [CTAB], [NaOH] and [PVA] on the silver sol formation rate were analyzed.

• Spectroscopic elucidation of new metal hetroscorpionates: A novel class of antifungal and antibacterial agents

  R. A. Sheikh, S. Shreaz, Maqsood Ahmad Malik, L. A. Khan, A. A. Hashmi

  Journal of Chemical and Pharmaceutical Research. 01/2010;

• Kinetics of MnO4- oxidation of succinic acid in aqueous solution of cetyltrimethylammonium bromide

  Maqsood Ahmad Malik, F. M. El-Nowaiser, N. Ahmad, Z. Khan

  International Journal Of Chemical Kinetics. 01/2010;
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  Oxidation of tyrosine by permanganate in presence of cetyltrimethylammonium bromide.

  Maqsood Ahmad Malik, Zaheer Khan

  Colloids and surfaces. B, Biointerfaces. 12/2009;

  In this paper we report the effect of cetyltrimethylammonium bromide, CTAB on the oxidative degradation of tyrosine by permanganate. The reaction rate bears a first-order dependence on the [MnO(4)(-)] under pseudo-first-order conditions (large excess of [tyrosine] for at least 10 times over [MnO(4)(... [more] In this paper we report the effect of cetyltrimethylammonium bromide, CTAB on the oxidative degradation of tyrosine by permanganate. The reaction rate bears a first-order dependence on the [MnO(4)(-)] under pseudo-first-order conditions (large excess of [tyrosine] for at least 10 times over [MnO(4)(-)]) in presence of 10.0x10(-4)moldm(-3) CTAB. The effect of total [CTAB] on the reaction rate was determined. When [CTAB] was less than its critical micelle concentration (CMC) the rate constants (k(psi)) values decreased from 18.5x10(-4) to 7.2x10(-4)s(-1). As the [CTAB] was greater than the CMC, the k(psi) values increase from 7.2x10(-4) to 15.8x10(-4)s(-1)at room temperature. The premicellar environment of CTAB strongly inhibits the reaction rate where as increase in rate constant ascribed to the incorporation of tyrosine and MnO(4)(-) in to the Stern layer of CTAB micelles. The reaction has acid-dependent and acid-independent paths and, in the former case, the zero-order kinetics with respect to [H(2)SO(4)] shifted to fractional-order at higher [H(2)SO(4)]. Experiments have been done to confirm the nature of Mn(IV) formed during the reduction of permanganate by tyrosine. The mechanism with the observed kinetics has been proposed and discussed. The presence of -OH group is responsible for the higher reactivity of tyrosine which easily transfers the proton to MnO(4)(-).
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  Role of cetyltrimethylammonium bromide (cationic surfactant) on the tryptophan-MnO(4)(-) reaction.

  Maqsood Ahmad Malik, Zaheer Khan

  Colloids and surfaces. B, Biointerfaces. 05/2009;

  Upon addition of permanganate to a solution of tryptophan (Trp), yellow-brown color species appears within the time of mixing of tryptophan in absence and presence of cetyltrimethylammonium bromide (CTAB), which was stable for some days. Spectroscopic and kinetic evidences suggest the formation of w... [more] Upon addition of permanganate to a solution of tryptophan (Trp), yellow-brown color species appears within the time of mixing of tryptophan in absence and presence of cetyltrimethylammonium bromide (CTAB), which was stable for some days. Spectroscopic and kinetic evidences suggest the formation of water-soluble colloidal MnO(2) as the most stable reduction product of MnO(4)(-). Carbon dioxide and ammonia are not formed as the oxidation products. Carbon-carbon double bond of indole moiety of Trp is responsible for the fast reduction of permanganate. Cetyltrimethylammonium bromide catalyses the permanganate oxidation of Trp with a rate enhancement of ca. 200-fold. Sub- and postmicellar catalytic effect of CTAB ascribed to the association/incorporation/solubilization of both reactants (MnO(4)(-) and Trp) with the CTAB aggregates and into the Stern layer of cationic micelles. Quantitative kinetic analysis of the rate constant-[CTAB] data has been performed on the basis of modified pseudo-phase model of the micelles. A comparison was made of the oxidation rates of different amino acids by permanganate. The order of the effectiveness was as follows: tryptophan>>tyrosine>>phenylalanine.
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  Submicellar catalytic effect of cetyltrimethylammonium bromide in the oxidation of ethylenediaminetetraacetic acid by MnO4(-).

  Maqsood Ahmad Malik, Zaheer Khan

  Colloids and surfaces. B, Biointerfaces. 07/2008; 64(1):42-8.

  The effects of cetyltrimethylammonium bromide (CTAB), sodiumdodecyl sulphate (SDS) and Triton X-100 (TX-100) on the oxidative degradation of ethylenediaminetetraacetic acid (EDTA) by MnO4(-) have been studied spectrophotometrically at 525 and 420 nm, respectively. It was found that cationic surfacta... [more] The effects of cetyltrimethylammonium bromide (CTAB), sodiumdodecyl sulphate (SDS) and Triton X-100 (TX-100) on the oxidative degradation of ethylenediaminetetraacetic acid (EDTA) by MnO4(-) have been studied spectrophotometrically at 525 and 420 nm, respectively. It was found that cationic surfactant catalyse the reaction rate while anionic and non-ionic have no effect. The premicellar environment of CTAB strongly catalyses the reaction rate which may be due to the favorable electrostatic binding of both reactants (MnO4(-) and EDTA) with the positive head groups of the CTAB aggregates. The influence of different parameters such as [MnO4(-)], [EDTA], [H(+)] and [surfactants] were also considered. The reaction follows the first- and fractional-order kinetics with respect to [MnO4(-)] and [EDTA]. The proposed mechanism and the derived rate law are consistent with the observed kinetics.

• Kinetics and Mechanism of Paracetamol Oxidation by Chromium(VI) in Absence and Presence of Manganese(II) and Sodiumdodecyl Sulphate

  Ilyas Mohammed, Maqsood Ahmad Malik, Syed Misbah Zahoor Andrabi, Khan Zaheer

  Research Letters in Physical Chemistry. 01/2007;

  The kinetics of paracetamol oxidation are first order each in [paracetamol] and [HClO4]. The kinetic study shows that the oxidation proceeds in two steps. The effects of anionic micelles of sodiumdodecyl sulphate (SDS) and complexing agents (ethylenediammine tetraacetic acid (EDTA) and 2,2′-bip... [more] The kinetics of paracetamol oxidation are first order each in [paracetamol] and [HClO4]. The kinetic study shows that the oxidation proceeds in two steps. The effects of anionic micelles of sodiumdodecyl sulphate (SDS) and complexing agents (ethylenediammine tetraacetic acid (EDTA) and 2,2′-bipyridyl (bpy)) were also studied. Fast kinetic spectrophotometric method has been described for the determination of paracetamol. The method is based on the catalytic effect of manganese(II) on the oxidation of paracetamol by chromium(VI) in the presence of HClO4 (= 0.23 mol dm−3). Optimum reaction time is 4 to 6 minutes at a temperature of 30∘C. The addition of manganese(II) ions largely decreased the absorbance of chromium(VI) at 350 nm. This reaction can be utilized for the determination of paracetamol in drugs.

• Preparation of silver nanoparticles using tryptophan and its formation mechanism

  Zoya Zaheer, Maqsood Ahmad Malik, F.M. Al-Nowaiser, Zaheer Khan

  Colloids and Surfaces B: Biointerfaces.

  A non-toxic route was used for the preparation of silver nanoparticles using tryptophan (Trp) as reducing/stabilizing agent in the presence of cetyltrimethyl ammonium bromide (CTAB). Role of water soluble neutral polymer poly(vinylpyrrolidone) (PVP) has been studied on the growth of yellow colour si... [more] A non-toxic route was used for the preparation of silver nanoparticles using tryptophan (Trp) as reducing/stabilizing agent in the presence of cetyltrimethyl ammonium bromide (CTAB). Role of water soluble neutral polymer poly(vinylpyrrolidone) (PVP) has been studied on the growth of yellow colour silver nanoparticle formation. The synthesized nanostructures were characterized by UV–Visible absorption spectroscopy, transmission electron microscopy (TEM) by observing the size and distribution of silver nanoparticles. As the reaction proceeded, particles grew up to about 10 and 20 nm in the presence and absence of PVP, respectively, as determined by TEM. The formed nanoparticles showed the highest absorption plasmon band at 425 nm. Rate of silver sol formation increases with the [Trp], [CTAB] and [PVP], reaching a limiting value and then decreases with the increase in concentrations of these reagents. It was observed that nanoparticles are spherical, aggregated and poly dispersed in the absence and presence of PVP, respectively. On the basis of kinetic data, a suitable mechanism is proposed and discussed for the silver sol formation.