Keratin cystine reactivity in microemulsion media: Influence of cosurfactant chain length

Abstract

The influence of n-alkanol chain length on keratin cystine reactivity in microemulsion media has been investigated. Microemulsions of the systems water/sodium dodecylsulfate/n-alkanol/n-dodecane incorporating a constant concentration of reducing (thioglycolic acid) or oxidising (hydrogen peroxide) agent were chosen as reaction media. The results obtained showed that keratin cystine reactivity was faster the longer the n-alkanol chain length, an effect related to the partition of reagent among the different microemulsion domains as well as to microstructure of the reaction media. Microemulsions with n-decanol possess a better defined droplet structure and therefore the local concentration effect of reagent in the aqueous droplets is higher than in microemulsions with n-pentanol.