On the hydrophobicity of nitrogen dioxide: could there be a "lens" effect for NO(2) reaction kinetics?

Nitric Oxide. 2009 Sep;21(2):104-9. doi: 10.1016/j.niox.2009.05.008. Epub 2009 Jun 18.

Abstract

Solvent "lens" effects for the reaction kinetics of NO(2) can be evaluated on the basis of published Henry's law constants for nitrogen dioxide in various solvents. Water-to-organic solvent partition coefficients were derived from Henry's law constants and used to assess the tendencies of NO(2) toward fleeing the aqueous environments and concentrating in biological hydrophobic media. It is concluded, based only on the estimated aqueous medium-to-cell membrane partition coefficient for NO(2), that such tendencies will be relatively small, and that they may account for an acceleration of chemical reactions in biological hydrophobic media with reaction kinetics that are first order on NO(2) by a factor of approximately 3+/-1. Thus, kinetic effects due to mass action will be relatively small but it is also important to recognize that because NO(2) will tend to dissolve in cell membranes, reactions with cell membrane components will not be hindered by lack of physical solubility at these loci. In comparison to other gases, nitrogen dioxide is less hydrophobic than NO, O(2) and N(2).

Publication types

  • Research Support, N.I.H., Extramural

MeSH terms

  • Algorithms
  • Cell Membrane / chemistry
  • Hydrophobic and Hydrophilic Interactions
  • Kinetics
  • Models, Chemical*
  • Nitrogen Dioxide / chemistry*
  • Nitrogen Dioxide / metabolism
  • Organic Chemicals / chemistry
  • Solvents / chemistry
  • Thermodynamics
  • Water / chemistry

Substances

  • Organic Chemicals
  • Solvents
  • Water
  • Nitrogen Dioxide