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Updated: Jul 12, 2026
12:06
Synthesis of High Purity Nonsymmetric Dialkylphosphinic Acid Extractants
Published on: October 19, 2017
Interaction of obidoxime with sarin in aqueous solution
P G Waser1, C M Alioth-Streichenberg, W H Hopff
1Department of Pharmacology, Zürich, Switzerland.
Archives of Toxicology
|January 1, 1992
Summary
Obidoxime (Toxogonin) interacts with sarin, forming phosphonylated compounds. This interaction increases sarin
Area of Science:
- Chemical Toxicology
- Analytical Chemistry
- Pharmacology
Background:
- Sarin is a highly toxic organophosphate nerve agent.
- Obidoxime is an oxime antidote used for organophosphate poisoning.
- Understanding the interaction between obidoxime and sarin is crucial for effective treatment.
Purpose of the Study:
- To investigate the interaction between obidoxime and sarin using analytical methods.
- To characterize the products of obidoxime-sarin interaction.
- To elucidate the mechanism of obidoxime's detoxifying effect.
Main Methods:
- UV-Vis spectrophotometry to monitor spectral changes.
- Thin-layer chromatography (TLC) to identify reaction products.
- 31P-Nuclear Magnetic Resonance (NMR) spectroscopy for structural analysis.
- Decomposition kinetics studies in buffered solutions.
Main Results:
- UV spectroscopy indicated immediate interaction between obidoxime and sarin.
- TLC and 31P-NMR confirmed the formation of mono- and di-phosphonylated obidoxime adducts.
- Decomposition of phosphonylated obidoxime was observed, with di-phosphonylated form degrading faster.
- Formation and decomposition rates were found to be pH-dependent.
Conclusions:
- Obidoxime effectively captures sarin molecules, increasing sarin's polarity.
- This increased polarity restricts sarin's passage across the blood-brain barrier.
- Obidoxime facilitates the renal elimination of sarin, contributing to its detoxifying effect.
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