Enzymatic chemistry of ferrocenes: micellar tuning of the glucose oxidase reactivity toward solubilized electrochemically generated n-alkylferricenium cations

Remarkable kinetic tuning of the glucose oxidase activity by the nature of micelle–alkylferrocene assemblies is realized during the electrochemical coupling between the enzyme reduced by d-glucose and the electrochemically generated alkylferricenium cations H(CH2)nFc+ (n=0, 2, 4–8) solubilized in micelles of neutral, positively and negatively charged surfactants (Triton X-100, CTAB and SDS, respectively) in the presence of d-glucose at pH 7. The relative electron-transfer rate increases 14 times for n-butylferrocene in CTAB and decreases by a factor of 3000 for n-pentylferrocene in SDS micelles relative to their reactivities in the neutral Triton X-100 medium.