Reduction Mechanism of L-Cysteine on Keratin Fibers Using Microspectrophotometry and Raman Spectroscopy
August 2005
in “
Biopolymers
”
TLDR L-cysteine slows down the breaking of bonds in hair due to electrostatic interactions.
The study investigated the reduction mechanism of L-cysteine (Cys) on keratin fibers in human hair using microspectrophotometry and Raman spectroscopy. It was found that Cys diffused into the hair in a non-Fickian manner, indicating electrostatic interactions between Cys's free amino groups and the anionic ions on the fiber surface. The disconnection of —SS— groups occurred at a slower rate than the diffusion of Cys, particularly at pH 9.0, suggesting that these electrostatic interactions decreased the reaction rate of Cys.
