Journal of the Chilean Chemical Society
versión On-line ISSN 0717-9707
CAMPOS, ANA; VILLALOBOS, CAROLINA y LISSI, EDUARDO. REACTION OF ALKYL GALLATES WITH DIPHENYL PICRYLHYDRACYL RADICALS IN SDS MICELLES. J. Chil. Chem. Soc. [online]. 2010, vol.55, n.4, pp.458-460. ISSN 0717-9707. http://dx.doi.org/10.4067/S0717-97072010000400010.
Diphenylpicrylhydracyl is a stable free radical that readily reacts with phenol groups. In the present work we have measured the reaction of DPPH with three alkyl gallates of different hydrophobicity: methyl gallate, propyl gallate, and octyl gallate. Experiments were carried out in acetate buffer (pH 5.0) in presence of several SDS concentrations. At surfactant concentrations higher than 20 mM, the gallates are almost totally associated to the micellar pseudophase. Under these conditions the rate of the reaction becomes almost independent of the length of the alkyl group. This indicates that the average localization of the gallate reactive group is almost independent of the solute hydrophobicity.