I am working on using raw keratin powder as a filler in film composites. However, keratin is not soluble in DMF, likely due to the presence of disulfide bonds. I need to cleave these disulfide bonds without significantly altering the properties of the keratin. I’ve tried using sodium sulfide for this purpose, but it leads to extensive degradation of the keratin. L-cystine has also been reported to cleave disulfide bonds, but I’m still uncertain whether it’s the best option or if another alternative might be more effective.

suggest some process to make keratin soluble in DMF.