The interaction between OPH and paraoxon at the air-water interface studied by AFM and epifluorescence microscopies

Xihui Cao, Mustapha Mabrouki, Sarita V. Mello, Roger Leblanc, Vipin K. Rastogi, Tu Chen Cheng, Joseph J. DeFrank

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5 Scopus citations


The paraoxon hydrolysis reaction catalyzed by organophosphorus hydrolase (OPH) monolayer at the air-water interface was studied. OPH-paraoxon interactions, occurring at the two-dimensional interface, by close-packed, highly orientated OPH monolayer, were investigated by several different surface chemistry techniques; e.g. surface pressure area isotherms, atomic force microscopy (AFM), and in situ epifluorescence microscopy. The characterization of OPH Langmuir and Langmuir-Blodgett films prepared in both the presence and absence of paraoxon, demonstrated significantly distinctive feature when compared with one another. Continuous growth of the OPH aggregates is a distinct phenomenon associated with hydrolysis, in addition to the pH changes in the local environment of the enzyme macromolecules.

Original languageEnglish
Pages (from-to)75-81
Number of pages7
JournalColloids and Surfaces B: Biointerfaces
Issue number2
StatePublished - Feb 10 2005



  • Atomic force microscopy
  • Organophosphorus hydrolase
  • Paraoxon

ASJC Scopus subject areas

  • Biotechnology
  • Colloid and Surface Chemistry
  • Physical and Theoretical Chemistry
  • Surfaces and Interfaces

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