Surface analysis of permanent wave processing hair using DART-MS

Permanent wave processing of hair is carried out at two processes as follows;
(A) Reducing agent (permanent wave 1 agent) makes the bridge construction between the keratin protein molecular chains of hair, especially disulfide (S-S) bond of cystine residue cleaved to thiol (-SH) group and hear results a wave and curl.
(B) Oxidizing agent (permanent wave 2 agent) makes -SH group oxidized to be reproduced S-S bond. As reducing agents used for permanent wave 1 agent, the thing of cosmetics approval, such as cysteamine hydrochloride and a butyrolactone thiol (brand name Spiera, other than quasi drugs, such as ammonium thioglycolate, acetyl cystein, and thiolactic acid, are used.
After hair is applying permanent wave processing and coloring repeatedly, the chemical structure of a keratin molecule and fine structure in the hair have been damaged and it resulted as damage hair. It is thought that hair becomes dryness and twining if the cuticle which covers hair is damaged, so it is important to investigate the surface structure of hair and its chemical structure changing.
DART (Direct Analysis in Real Time), a direct atmospheric pressure ionization source, is capable of analyzing samples directly with little or no sample preparation. Here, analysis of the ingredient which has deposited on the permanent wave processing hair surface was tried using this DART combined with a mass spectrometer.