Analysis of Heterogeneous Reaction Between Reducing Agents and Keratin Fibers Using Raman Spectroscopy and Microspectrophotometry
April 2013
in “
Journal of molecular structure
”
TLDR The study found that thioglycolic acid breaks down hair bonds more consistently than l-cysteine, which is less damaging to hair.
The study investigated the heterogeneous reaction between reducing agents (thioglycolic acid (TG) and l-cysteine (CYS)) and keratin fibers in human hair using Raman spectroscopy and microspectrophotometry. It was found that TG diffused into the hair and disconnected disulfide (–SS–) groups in a Fickian manner, penetrating beyond the cuticle into the cortex region. In contrast, CYS showed a slower reaction rate and limited penetration into the cortex due to electrostatic interactions with the fiber surface, resulting in less damage to the hair. The findings indicated that hair treated with CYS was less damaged compared to TG-treated hair.
