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Updated: Aug 18, 2026

Synthesis of High Purity Nonsymmetric Dialkylphosphinic Acid Extractants
Published on: October 19, 2017
Molecular interaction between organophosphorus acid anhydrolase and diisopropylfluorophosphate
Jiayin Zheng1, Celeste A Constantine, Liang Zhao
1Department of Chemistry, University of Miami, Coral Gables, Florida 33124-0431, USA.
Abstract:
Organophosphorus acid anhydrolases (OPAA; E.C.3.1.8.2) are a class of enzymes that hydrolyze a variety of toxic acetylcholinesterase-inhibiting organophosphorus (OP) compounds, including pesticides and fluorine-containing chemical nerve agents. In this paper, subphase conditions have been optimized to obtain stable OPAA Langmuir films, and the diisopropylfluorophosphate (DFP) hydrolysis reaction catalyzed by OPAA in aqueous solution and at the air-water interface was studied. OPAA-DFP interactions were investigated utilizing different spectroscopic techniques, that is, circular dichroism and fluorescence in aqueous solution and infrared reflection absorption spectroscopies at the air-water interface. The characterization of OPAA and its secondary structure in aqueous solution and as a monolayer at the air-water interface in the absence and in the presence of DFP dissolved in aqueous solution or in the aqueous subphase demonstrated significantly distinctive features. The research described herein demonstrated that OPAA can be used in an enzyme-based biosensor for DFP detection.
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