research Preparation and Characterization of Soluble Wool Keratin for Human Hair Care
Soluble wool keratin was prepared by modifying disulfide bonds of cysteine to carboxymethylalanyl disulfide (CMAD) groups using thioglycolic acid under alkaline conditions. The resulting carboxymethylalanyl disulfide keratin (CMADK) had a desirable molar mass and some molecules exhibited a helical structure. CMADK with low molar mass, prepared at pH 13.5 and 60°C for 3 hours, was added to permanent waving agents. This treatment significantly reduced hair damage even after three repetitions, demonstrating CMADK's effectiveness in preventing hair damage from bleaching and permanent waving.