Zia Ur Rahman

Centre of Excellence in Molecular Biology, Lāhaur, Punjab, Pakistan

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Publications (24)58.43 Total impact

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    ABSTRACT: Recent advancement in technologies like fermentation procedures resulted in the increased yields of recombinant proteins of biopharmaceutical and medicinal importance. Consequently, there is an important task to develop simple and easily scalable methods that facilitate the production of high quality recombinant protein. Most of the recent reports described the expression of Recombinant human IL-1receptor antagonist in Escherichia coli using isopropyl-β-D-thiogalacto pyranoside (IPTG), a non-metabolizable and expensive compound, as expression inducer. In the present study, we describe the expression and one step purification of gallbladder derived rhIL-1Ra by auto-induction in E. coli. This method involves special media recipes that automatically induced the target protein expression from T7 promoter and allow the production of the target protein in high yield than conventional IPTG induction method. In addition to fermentation process improvements, one step purification strategy is important to make the process economical. We developed a single step cation exchange chromatography and obtained rhIL-1Ra 300 mg/L with of 98% purity. Purified protein was characterized by SDS-PAGE and by IEX-HPLC. Described method may use to develop process scale method for production of rhIL-1Ra and other recombinant proteins. This article is protected by copyright. All rights reserved.
    No preview · Article · Dec 2015 · Biotechnology and Applied Biochemistry
  • Zia Ur Rahman · Tingting Zhang · Siwen Cui · Daoai Wang
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    ABSTRACT: In this paper magnetic nanocomposite catalysts, with a single gold catalytic layer (Fe3O4@SiO2-Au and Fe3O4@SiO2-Au@mSiO2), double gold catalytic layers (Fe3O4@SiO2-Au@mSiO2-Au), and with one gold layer and one silver layer (Fe3O4@SiO2-Au@mSiO2-Ag), were prepared through simple steps. Different techniques were used for characterization of the as prepared nanocomposite catalysts, such as transmission electron microscopy (TEM), X-ray diffraction (XRD), a vibrating sample magnetometer (VSM), energy-dispersive X-ray spectroscopy (EDX) etc. The catalysts were used for the catalytic reduction of 4-nitrophenol (4-NP) to 4-aminophenol (4-AP) in the presence of NaHB4. All the nanocomposite catalysts showed very good catalytic activity; however the nanocomposites with double catalytic layers (Fe3O4@SiO2-Au@mSiO2-Au and Fe3O4@SiO2-Au@mSiO2-Ag) showed excellent catalytic activity for the reduction reaction of 4-nitrophenol. Due to the magnetic core, the nanocomposite catalysts showed magnetic properties and can be easily separated and recycled many times without any loss in activity. In the case of nanocomposite catalysts with Au nanoparticles protected by silica (Fe3O4@SiO2-Au@mSiO2) indicated better recyclability compared to other nanocomposites.
    No preview · Article · Nov 2015 · RSC Advances
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    Preview · Article · Nov 2015
  • Li Su · Wenjie Qin · Huige Zhang · Zia Ur Rahman · Cuiling Ren · Sudai Ma · Xingguo Chen
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    ABSTRACT: MFe2O4 (M=Mg, Ni, Cu) magnetic nanoparticles (MNPs) were found to have catalytic activities similar to those of biological enzymes such as catalase and peroxidase. These nanomaterials, as bifunctional catalase/peroxidases (KatGs), not only could catalyze H2O2 to produce hydroxyl radicals, which oxidized peroxidase substrate to produce color, but also could catalyze the decomposition reaction of H2O2 into water and oxygen directly in the same condition through the catalase-like activity. And it was also found that the amount of generated hydroxyl radicals and oxygen was related to the concentration of MFe2O4 (M=Mg, Ni, Cu) MNPs. The peroxidase-like catalytic behavior of MFe2O4 MNPs was analyzed in detail. Under the optimized conditions, NiFe2O4 MNPs were used as a colorimetric biosensor for the detection of 9.4×10(-7)-2.5×10(-5)molL(-1) glucose with a limit of detection (LOD) of 4.5×10(-7)molL(-1). The sensor was successfully applied to glucose detection in urine sample.
    No preview · Article · Jan 2015 · Biosensors & Bioelectronics
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    ABSTRACT: In this work, core-satellites nanostructural composites have been synthesized through self-assembly combined with in situ growth strategy for catalytic degradation of common organic contaminants. At first, a three-component microsphere catalyst support containing alkyl-functionalized Fe3O4 magnetite core and a layered chitosan (CTS) shell has been constructed for loading of gold nanoparticles (Au NPs). Wherein, the Fe3O4 microsphere core is in favor for recycling and the formation of a hexadecyltrimethoxysilance@CTS (C-16@CTS) layer effectively increases its surface area and provides more docking sites for small Au satellite NPs to construct core-satellites nanostructure. Through electrostatic interaction and coordination, small Au NPs automatically assembled on the surface of support which served as seeds for further in situ growth of bigger stable Au NPs. The obtained catalyst was stable and had enhanced performance for fast catalytic reduction and fading of common organic contaminants, including 4-nitrophenol (4-NP), methylene blue (MB), Congo red (CR), rhodamine B (RhB), rhodamine 6G (R6G), acid orange (AO) and methyl orange (MO). No significant inactivation of the catalyst was observed even after recycling for eleven cycles or stored for more than 1 month. In addition, the catalyst was used for effective degradation of organic pollutant in Yellow River water sample, which indicated its potential for practical applications in water pollutant removal and environmental remediation.
    No preview · Article · Oct 2014 · The Chemical Engineering Journal
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    ABSTRACT: In this study, an on-line sample preconcentration technique, field-amplified sample injection combined with water removal by electroosmotic flow pump, was applied to realize a highly sensitive chiral analysis of β-blocker enantiomers by microemulsion electrokinetic chromatography (MEEKC). The introduction of a water plug in capillary before the electrokinetic injection provided the effective preconcentration of chiral compounds. And then the water was moving out of the column from the injection end under the effect of the electroosmotic flow (EOF), which avoided dilution of the stacked β-blocker enantiomers concentration suffering from the presence of water in separation buffer. Moreover, the addition of H3PO4 and methanol in the sample solution greatly improved the enhancement efficiency further. Under optimized conditions, more than 2700-fold enhancement in sensitivity was obtained for each enantiomer of bupranolol (BU), alprenolol (AL) and propranolol (PRO) via electrokinetic injection. Limits of detection were 0.10, 0.10, 0.12, 0.11, 0.02 and 0.02 ng/mL for S-BU, R-BU, S-AL, R-AL, S-PRO and R-PRO, respectively. Eventually, the proposed method was successfully applied to the determination of BU, AL and PRO in serum samples with good recoveries ranging from 93.4 to 98.2%.This article is protected by copyright. All rights reserved
    No preview · Article · Oct 2014 · Electrophoresis
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    ABSTRACT: he Chemical Composition and antimicrobial activity of peel essential oil of sweet orange Citrus grown in Peshawar, Pakistan were investigated. The major chemical composition concentration of essential oil were D-Limonene was 95.62%, beta-myrcene was 2.78%, alpha-pinene was 0.75%, n-octyl acetate was 0.32%, beta pinene was 0.2% and beta farnesene was 0.09%. The antimicrobial activity of sweet orange peels oil were evaluated using well diffusion methods towards 4 bacteria and 3 fungal cultures. The results were compared with those synthetic antibiotics Gentamycin, Tetracyclin, Fluconazole and Nystatine. The Salmonella typhi were inhibited by essential oil with inhibition zone 13mm (50µL), 10mm (25µL) and 06mm (10µL). The Staphylococcus aureus ATCC6538 with the inhibition zone were 21(50µL), 18mm (25µL) and 07mm (10µL). No inhibition zone was observed for rest of bacteria E. coli and B. cereus. While all the tested fungal strains were showed a strong resistance to these oils.
    Full-text · Dataset · Feb 2014
  • Zia ur Rahman · Yanhua Ma · Jing Hu · Yinyin Xu · Weifeng Wang · Xingguo Chen
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    ABSTRACT: The effect of gold nanoseeds with different sizes on the gold shell was investigated. Gold nanoparticles of two different sizes (3 nm and 15 nm) were prepared and attached to the surface of amine functionalized silica coated iron oxide nanoparticles. The gold nanoparticles assembled on the surface were used as seeds for further gold shell formation. It was observed that the amount of Au attached to iron oxide nanoparticles is higher for bigger gold nanoseeds as compared to smaller gold nanoseeds. Similarly, after the formation of gold shell, a higher amount of Au was found for larger gold nanoparticles. However, both transmission electron microscopy (TEM) and scanning electron microscopy (SEM) results show that a complete, uniform, and compact gold shell was formed in the case of using small gold nanoseeds, but for larger gold nanoseeds the shell formed was discontinuous and was not uniform, while most of the gold nanoparticles were found to be aggregated on the surface. The nanocomposites showed high efficiency in catalysis for the reduction of 4-nirophenol, among which Nanocomp-2, with a thin stable gold shell showed excellent catalytic activity and reusability. All of the nanocomposites have high magnetization values and can be easily separated from the reaction mixture using a magnet and can be reused.
    No preview · Article · Jan 2014 · RSC Advances
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    Full-text · Article · Dec 2013
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    ABSTRACT: Citation: Zar MS, Shahid AA, Shahzad MS, Shin KJ, Lee HY, et al. (2013) Forensic DNA Typing of Old Skeletal Remains Using AmpFlSTR ® Identifiler ® PCR Amplification Kit. J Forensic Res 5: 211. doi:10.4172/2157-7145.1000211 Copyright: © 2013 Zar MS. This is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited. Introduction Problems occur during DNA typing of old skeletal remains with low quantities of template DNA. Low template DNA (LT DNA) or Low copy number DNA (LCN DNA) refer to any small amount of DNA (≤ 100-200 pg/μL) present in degraded DNA sample. More recently, LCN referred to any DNA sample or DNA profile where stochastic effects are present and/or where the alleles detected are below a laboratory defined stochastic threshold. Stochastic effects includes allele drop out, allelic drop-in, heterozygous peak height imbalance, locus drop-out and elevated stutter peaks [1,2]. Extraction and quantification of DNA for all DNA samples are very necessary. However, some time quantification results may be unreliable, particularly in case of degraded DNA samples, and results with nil/low quantity of DNA give full profiles and significant quantification results give nil/partial DNA profiles [3]. There are several approaches to analyze old skeletal remains with low quantity of DNA. These are: using highly effective DNA extraction method, increasing sensitivity of PCR amplification and consensus approach [3,4]. Consensus approach is more reliable and reproducible [5,6]. The aim of this study was to improve DNA typing of old skeletal remains, through a multiplex AmpFlSTR ® Identifiler ® PCR amplification kit, using a highly effective DNA extraction method, increasing sensitivity of PCR amplification and applying consensus approach. Methodology Collection of old skeletal remains 24 human old skeletal remains were collected from 200-500 years old mass graves of Pakistan for DNA typing. Approval for sample collection was obtained from the ethical review committee of the Centre of Excellence in Molecular Biology, University of the Punjab Lahore Pakistan. The samples were labeled, photo-documented and stored at -20°C till use. Cleaning, pre-treatment and grinding of samples Cleaning, pre-treatment and grinding of samples were carried out in forensic research laboratory, CEMB, University of the Punjab Lahore Pakistan. The samples were handled with gloved hands and forceps to avoid contamination by skin cells/sweat. The outer surfaces of bone samples were sanded with a motor drill and a dental bur to remove potential contamination. Each bone sample was broken into small fragments using a dental diamond disk and irradiated with ultraviolet light for 10-15 minutes. The bone fragments were treated mechanically and chemically with scalpel blades, dremel tool, 10 % bleach, distilled water and 95 % ethanol to remove the remaining contaminated soil, inhibitory substances and other dirt and debris, and placed in a sterilized fume hood to air-dry overnight. The samples were grinded into fine powder using liquid nitrogen and a SPEX 6750 Freezer⁄Mill (SPEX CertiPrep, Metuchen, NJ). The bone powder were transferred to a 15 mL falcon tube and stored at -20°C until DNA extraction. Abstract Background: In this study DNA typing of old skeletal remains was improved through AmpFlSTR
    Full-text · Dataset · Dec 2013
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    ABSTRACT: Due to the unusual properties of the structure, the metal organic frameworks (MOFs) have received great interest in separation science. However, the most existing methods for the applications of MOFs in separation science require an off-line procedure to prepare the materials. Here, we report an in situ, layer-by-layer self-assembly approach to fabricate MIL-100(Fe) coated open tubular (OT) capillary columns for capillary electrochromatography. By a controllable manner, the OT capillary columns with a tailored MIL-100(Fe) coating have been successfully synthesized. The results of SEM, XRD, FT-IR, and ICP-AES indicated that MIL-100(Fe) was successfully grafted on the inner wall of the capillary. Some neutral, acidic and basic analytes were used to evaluate the performance of the MIL-100(Fe) coating OT capillary column. Because of the size selectivity of lattice aperture and hydrophobicity of the organic ligands, three types of analytes were well separated with this novel MIL-100(Fe) coating OT capillary column. For three consecutive runs, the intra-day relative standard deviations (RSDs) of migration time and peak areas were 0.4-4.6% and 1.2-6.6%, respectively. The inter-day RSDs of migration time and peak areas were 0.6-8.0% and 2.2-9.5%, respectively. The column-to-column reproducibility of retention time was in range of 0.6-9.2%. Additionally, the 10 cycles OT capillary column (10-LC) could be used for more than 150 runs with no observable changes on the separation efficiency.
    No preview · Article · Nov 2013 · Analytical Chemistry
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    ABSTRACT: Multifunctional nanocomposites with mesoporous silica having superparamagnetic, near-infrared (NIR) plasmon resonance, and catalytic behavior, were synthesized. These nanocomposites, with an inner magnetite core, an outer mesoporous silica shell, and a gold shell sandwiched between a thin silica layer and a thick outer silica shell, were characterized using different techniques, such as transmission electron microscopy, X-ray diffraction, fourier transform infrared spectroscopy, vibrating sample magnetometer, UV–vis spectroscopy, X-ray photoelectron spectrometry, dynamic light scattering, zeta potential, N2 adsorption/desorption, and thermal gravimetric analysis. The results indicated that the nanocomposites have high magnetization (21.4 emu/g) due to the inner magnetite core, significant absorbance in the NIR region due to the gold shell, large surface area (315 m2/g), and mesopores (2.1 nm) in the outer silica shell. The outer mesoporous silica shell was investigated for adsorption and release of drug as well as for attaching of dye molecules, while the gold shell was investigated its catalytic behavior. These multifunctional nanocomposites show adsorption and sustained release of ibuprofen, and also have excellent catalytic behavior.
    No preview · Article · Apr 2013 · The Chemical Engineering Journal
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    ABSTRACT: In this paper, we established a new on-line method using micelle to solvent stacking (MSS) technique combining with large amount sample electrokinetic stacking injection (LASEKSI) for the analysis of cationic molecules. In this MSS-LASEKSI, by modulating the integral EOF across the capillary, a equilibrium state was formed and can be maintained for a long time, leading to the continuous stacking of the analytes on the basis of MSS. Thereby, an extremely large amount sample was permitted to be injected into the capillary and then an improved enrichment fold can be achieved comparing with the each case. The variables affecting the performance of MSS-LASEKSI were investigated and discussed. Under the optimized conditions, 6.3×10(3)- and 6.4×10(2)-fold enrichment in peak heights upon normal CZE method (injected at 0.5psi for 3s) and number of plates of 2.9×10(6) and 6.5×10(5) were attained for berberine and theophylline, respectively. The developed method described here may provide prospects for exploiting a new concentration technique to achieve higher enrichment factor.
    No preview · Article · Sep 2012 · Journal of Chromatography A
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    ABSTRACT: In this report, graphene oxide-Fe(3)O(4) magnetic nanocomposites were demonstrated to possess intrinsic peroxidase-like activity and enhanced affinity toward H(2)O(2). The nanocomposites retain their magnetic properties and can be effectively separated by a magnet. Significantly, they were proved to be novel peroxidase mimetics which could quickly catalyze oxidation of the peroxidase substrate 3,3,5,5-tetramethylbenzidine (TMB) in the presence of H(2)O(2), producing a blue-colored solution. Kinetic analysis indicates that the catalytic behavior is in accord with typical Michaelis-Menten kinetics and follows a ping-pong mechanism. On the basis of the high activity, the reaction provides a simple, sensitive and selective method for colorimetric detection of glucose in diabetic urine.
    No preview · Article · May 2012 · Nanoscale
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    ABSTRACT: Magnetic iron oxide nanoparticles were prepared by chemical co-precipitation method and then modified with sodium citrate. These iron oxide nanoparticles were characterized by transmission electron microscopy (TEM), X-ray diffractometer (XRD), and vibrating sample magnetometer (VSM). BSA was adsorbed on these citrate modified nanoparticles using two types of buffers (acetate buffer, pH 4.0, 4.7 and phosphate buffer, pH 7.4). The results showed that the maximum adsorption of BSA was 83 mg/g at its isoelectric point (pH 4.7). Fourier-transform infrared spectroscopy (FTIR) was used to confirm the attachment of citrate groups and BSA on the prepared magnetic nanoparticles. BSA was desorbed from nanoparticles under alkaline conditions, which was confirmed by SDS–PAGE electrophoresis, UV-vis and fluorescence spectra. The desorbed BSA showed small changes in its structure. The adsorption results indicated that BSA adsorption on citrate modified iron oxide nanoparticles occurred mainly by electrostatic mechanism.
    No preview · Article · Mar 2012 · Journal of Nanoscience and Nanotechnology
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    ABSTRACT: In this study, the interaction between C.I. Acid Orange 7 (AO7) and human serum albumin (HSA) was firstly investigated using nuclear magnetic resonance (NMR) spectroscopy in combination with fluorescence quenching spectroscopy, three-dimensional fluorescence spectroscopy, UV–vis absorption spectroscopy, Fourier transform infrared (FT-IR) spectroscopy, circular dichroism (CD) spectroscopy and molecular modeling method in vitro. The results of NMR data confirmed that AO7 indeed interacted with HSA, and the hydrophobic portion of AO7 should be embedded to the hydrophobic pocket of HSA. The fluorescence quenching analysis revealed that AO7 can bind to HSA. The conformational change of HSA in the presence of AO7 was confirmed by synchronous fluorescence, three-dimensional fluorescence, UV–vis absorption, FT-IR and CD spectra. The binding distance between AO7 and tryptophan residue of HSA was calculated by the efficiency of fluorescence resonance energy transfer. Molecular modeling showed that hydrophobic force and hydrogen bonds were the major interaction between AO7 and HSA.
    No preview · Article · Mar 2012 · Dyes and Pigments
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    ABSTRACT: Guanidine group (Gnd) functionalized magnetic nanoparticles (Fe3O4@SiO2@NH2-Gnd) were synthesized and characterized in this work for the first time. The characterization of Fe3O4@SiO2@ NH2-Gnd nanoparticles was demonstrated by transmission electron microscopy, X-ray diffraction, Fourier transform infrared spectra, vibration sample magnetometer, and zeta potential analyzer. The novel multifunctional nanoparticles were served as a solid-phase extraction sorbent for easy isolation and preconcentration of acidic protein from aqueous solution only using a magnet. Bovine serum albumin (BSA) was selected as a model protein and the main experimental parameters influencing the adsorption and desorption efficiency were investigated and optimized. Under the optimum conditions, the particles reached saturated adsorption within 20 min and exhibited significant specific recognition for the acidic proteins. Fifteen fold enrichment efficiency was achieved and the detection limits was 45 ng x mL(-1) for BSA by capillary electrophoresis (CE). The practical application of the novel nanoparticles as a sorbent for the isolation and preconcentration of acidic proteins from basic proteins was demonstrated by effective separation and enrichment of bovine serum albumin from lysozyme and cytochrome C mixture, which was assayed by CE.
    No preview · Article · Dec 2011 · Journal of Nanoscience and Nanotechnology
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    ABSTRACT: In the present study Hydrogeomorphological survey has been carried out along the Yamuna River in parts of Agra district U.P, India. The satellite image of IRS-1 D, LISS III has been used to delineate the hydrogeomorphological units. The base map has been prepared from survey of India toposheets on 1:50000 scale. The study is aimed to assess and to delineate groundwater potential zones for future development and exploration. The different hydrogeomorphic units and features identified using remote sensing data and conventional information with limited ground truth are alluvial plain, flood plain, flood prone area/palaeochannels and ravines etc. The groundwater potential of each geological and geomorphologic unit has been evaluated in order to obtain a complete hydrogeological picture of Agra district. The final result shows the prosperous groundwater zones in the study area and can be helpful in better planning and management of groundwater resources especially in hard rock terrains.
    Full-text · Article · Jan 2009 · Journal of Environmental Research And Development
  • Nazim Muradov · Zia Ur Rahman
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    ABSTRACT: The synthesis and characterization of radially-aligned carbon filaments (RACF) produced from light hydrocarbons are reported. RACF grow spontaneously on the surface of a resistively heated (1100-1700 degrees C) carbon yarn exposed to C1-C3 hydrocarbons (methane, ethylene, propane) as carbon precursors. The diameter of the RACF depends on the temperature, exposure time, nature of hydrocarbon, and it ranges from 700 nm to 40 microm, with the length of the carbon filaments reaching up to 800 microm. The morphology and microstructure of the produced carbon filaments were analyzed by a number of materials characterization techniques, and it was shown that they feature a tree-ring type structure made of turbostratic carbon layers. RACF are characterized by the presence of cracks (50-100 nm in width) between the consecutive "tree-rings" and a crenulated structure of the exterior surface of the filaments. The RAFC growth mechanism is yet to be fully understood. Pros and cons for the catalytic versus non-catalytic growth models for the RACF are discussed in the paper.
    No preview · Article · Oct 2008 · Journal of Nanoscience and Nanotechnology
  • Hui Chen · Jinhai Wang · Zia ur Rahman · James G. Worden · Xiong Liu · Qiu Dai · Qun Huo
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    ABSTRACT: Sand particles from Cancun, Mexico were studied using a number of advanced spectroscopic and microscopic techniques. The main chemical composition of sand particles was confirmed to be calcium carbonate by X-ray photoelectron spectroscopy and IR spectroscopic analysis. X-ray diffraction analysis revealed that the sand particles are aragonite, which has an Orthorhombic—Dipyramidal crystal structure. The morphological study of the sand particles by scanning electron microscopy and transmission electron microscopy revealed the presence of a highly porous channel-like structure in the sand particles. The sorption isotherm indicates that Cancun sand is a mesoporous material. The specific surface area of Cancun sand was determined to be 2.259m2/g by BET measurement, which is significantly higher than that of Florida sand and other forms of natural aragonite and calcite. Furthermore, it was found that the porous sand particles can adsorb gold nanoparticles of the size of a few nanometers very efficiently. The distribution of gold nanoparticles demonstrated a channel-like porous inner structure of the sand particles. We also prepared a polymer composite material by mixing the sand particles with a poly(methyl methacrylate) matrix. SEM analysis of the composite materials showed a good interfacial adhesion between sand particles and polymer matrix. These results suggest that Cancun sand, as a natural macro- and mesoporous material, may find promising applications in filtration, pollution control, composite materials and biomaterials development.
    No preview · Article · Jul 2007 · Journal of Materials Science

Publication Stats

184 Citations
58.43 Total Impact Points

Institutions

  • 2015
    • Centre of Excellence in Molecular Biology
      Lāhaur, Punjab, Pakistan
  • 2012-2015
    • Lanzhou University
      • State Key Laboratory of Applied and Organic Chemistry
      Kao-lan-hsien, Gansu Sheng, China
  • 2013
    • University of the Punjab
      • Centre for Excellence in Molecular Biology
      Lāhaur, Punjab, Pakistan
  • 2007-2008
    • University of Central Florida
      • • Florida Solar Energy Center (FSEC)
      • • Department of Physics
      Orlando, Florida, United States