TITLE

Photonic crystal sensor for organophosphate nerve agents utilizing the organophosphorus hydrolase enzyme

AUTHOR(S)
Walker, Jeremy P.; Kimble, Kyle W.; Asher, Sanford A.
PUB. DATE
December 2007
SOURCE
Analytical & Bioanalytical Chemistry;Dec2007, Vol. 389 Issue 7/8, p2115
SOURCE TYPE
Academic Journal
DOC. TYPE
Article
ABSTRACT
We developed an intelligent polymerized crystalline colloidal array (IPCCA) photonic crystal sensing material which reversibly senses the organophosphate compound methyl paraoxon at micromolar concentrations in aqueous solutions. A periodic array of colloidal particles is embedded in a poly-2-hydroxyethylacrylate hydrogel. The particle lattice spacing is such that the array Bragg-diffracts visible light. We utilize a bimodular sensing approach in which the enzyme organophosphorus hydrolase (OPH) catalyzes the hydrolysis of methyl paraoxon at basic pH, producing p-nitrophenolate, dimethylphosphate, and two protons. The protons lower the pH and create a steady-state pH gradient. Protonation of the phenolates attached to the hydrogel makes the free energy of mixing of the hydrogel less favorable, which causes the hydrogel to shrink. The IPCCA’s lattice constant decreases, which blueshifts the diffracted light. The magnitude of the steady-state diffraction blueshift is proportional to the concentration of methyl paraoxon. The current detection limit is 0.2 μmol methyl paraoxon per liter.
ACCESSION #
27657807

 

Related Articles

  • Anisotropic-network-stabilized ferroelectric gels for active matrix addressing. Hikmet, R. A. M.; Boots, H. M. J.; Michielsen, M. // Journal of Applied Physics;5/15/1996, Vol. 79 Issue 10, p8098 

    Deals with a study which examined the switching behavior of ferroelectric gels by polymerization of liquid crystal diacrylates in mixtures of nonreactive molecules showing the ferroelectric phase. Experimental details; Results and discussion; Conclusions.

  • Influence of penetration time on the structure and conductivity of Sm-modified BaTiO powders. Fu, Dongsheng; Hao, Sue; Qiang, Liangsheng // Journal of Materials Science: Materials in Electronics;Apr2013, Vol. 24 Issue 4, p1208 

    In this study BaTiO powders were prepared by the sol-gel method. And the gaseous penetration technique was adopted to improve the conductivity of the BaTiO powders. The resistivity of BaTiO powders decreased from 4.3 × 10 to 1.75 × 10 Ω m as the penetration time increased from 1 to 5...

  • New age crystals. Grier, David G. // Nature;10/23/1997, Vol. 389 Issue 6653, p784 

    Reports on a new class of composite materials which can detect trace components in complex solutions as of October 23, 1997. The use of chemically functionalized gels; The delicate balance between the polymer and the solvent; How chemically functionalized gels can be tailor-made; The use of the...

  • Sol-gel Chemistry in Medicinal Science. Coradin, Thibaud; Boissi�re, Michel; Livage, Jacques // Current Medicinal Chemistry;2006, Vol. 13 Issue 1, p99 

    The sol-gel process is an inorganic polymerization process taking place in mild conditions, allowing the association of mineral phases with organic or biological systems. The possibility to immobilize drugs, enzymes, antibodies and even whole cells without loss of their biological activity led...

  • New Possibilities for Biospecific Chromatography. Valuev, I. L.; Valuev, L. I.; Platé, N. A. // Applied Biochemistry & Microbiology;Jul/Aug2003, Vol. 39 Issue 4, p422 

    Polyacrylamide hydrogels covalently modified with duck eggwhite ovomucoid were synthesized by radical copolymerization. These hydrogels can protect insulin (physically immobilized therein) against the action of proteolytic enzymes. Biospecific interaction of the polysaccharide component of the...

  • Gel-forming Characteristics of Surimi from White Croaker under the Inhibition of the Polymerization and Degradation of Protein. Phu, Ngo Van; Morioka, Katsuji; Itoh, Yoshiaki // Journal of Biological Sciences;2010, Vol. 10 Issue 5, p432 

    No abstract available.

  • Rheological properties of microcrystalline chitosan gels. Jakobsons, E.; Laka, M.; Chernyavskaya, S. // Mechanics of Composite Materials;May2007, Vol. 43 Issue 3, p259 

    The procedure of thermocatalic processing of chitosan developed allows one to decrease its degree of polymerization to the so-called leveling-off degree and, after the precipitation from a solution and washing, to obtain hydrogels of microcrystalline chitosan (MCC.) The flow curves of the MCC...

  • Two-Step Fuzzy Multicriteria Ranking of Whole Cells Immobilization Methods for Biosensor/Biocatalyst Selection/Synthesis. Batzias, Fragiskos // AIP Conference Proceedings;11/29/2007, Vol. 963 Issue 1, p586 

    This work deals with the design/development of a methodological framework, under the form of an algorithmic procedure, including 23 activity stages and 7 decision nodes, for fuzzy multicriteria ranking of whole cells immobilization methods (WIMs) for biosensor/biocatalyst selection/synthesis. An...

  • ultrafilter.  // Taber's Cyclopedic Medical Dictionary (2009);2009, Issue 21, p2399 

    An encyclopedia entry for "ultrafilter," a filter by which colloidal particles may be separated from their dispersion medium or from crystalloids, is presented.

Share

Read the Article

Courtesy of THE LIBRARY OF VIRGINIA

Sorry, but this item is not currently available from your library.

Try another library?
Sign out of this library

Other Topics