The retention times of the analytes were 2.6 min for OHP and 4.8 min for cysteic acid
(40 ug mL-1).
Our measurement of the wool after 123 days from the irradiation definitively confirmed cysteic acid
as the final product also in the case of electron beam irradiation (Figures 4 and 5).
Methionine and cysteine were determined as methionine sulfone and cysteic acid
after cold performic acid oxidation overnight and samples were then hydrolysed with 7.5 N HCl at 110[degrees]C for 24 h using an AA Analyser (Hitachi L-8800, Japan).
Cysteine and methionine were analyzed after performic acid oxidation and determined as cysteic acid
and methionine sulfone, respectively.
Phase A Ceteareth-20 25.0 Cyclomethicone 4.0 Phenoxyethanol(and) methylparaben 0.5 (and) ethylparaben (and) butylparaben (and) propylparaben Mineral oil 6.0 PEG-7 glycerol cocoate 10.0 Cyclopentasiloxane (and) 10.0 dimethicone crosspolymer (and) dimethicone/vinyl dimethicone crosspolymer (and) dimethiconol Phase B Maltodextrin (and) caffeine (and) 2.0 paullinia cupana seed extract (and) carnitine (and) microcrystalline cellulose (and) cysteic acid
(and) pantetheine sulfonate Distilled water 27.7 Glycerin 4.0 Propylene glycol 9.0 Fragrance 1.0 0.2% solution of Red 40 0.8 in deionized water PROCEDURE: Heat ceteareth-20 to 80[degrees]C with gentle mixing.
Methionine and cysteine were determined as methionine sulphone and cysteic acid
using an AA Analyzer (Hitachi L-8900, Japan) after cold performic acid oxidation overnight and hydrolyzing with 7.5 N HCl at 110[degrees]C for 24 h.
The tensile strength of hair is improved by building electrostatic bonds between amino groups and anionic side chains of the amino acids of hair such as cysteine, cysteic acid
and glutamic acid.
Cystine was determined as cysteic acid
and methionine as methionine sulphone after peroxidation with performic acid and pre-column derivation using phenylisothiocyanate (L-8900, Automatic Amino Acid Analyzer; Hitachi, Japan).