The dissolution of human hair using ionic liquids through COSMO-RS predication and experimental verification

Keratin, which extracted from human hair, has great potential in biomedical applications because of its excellent biocompatibility. Efficient dissolution of human hair in the solvent is the key step for its extraction. In this work, 143 kinds of ILs and three model compounds were used to predict the dissolving ability of ILs for human hair dissolution by using COSMO-RS. Moreover, five-imidazole based ILs were screened out from 143 kinds of ILs to verify the predicted dissolving ability for human hair. The results shown that ILs with cation [Emim](+) and anions OAc-, DEP- have the strong dissolving ability of human hair. Furthermore, the effect of dissolving temperature, mass ratio, water content and the recycle performance of ILs have also been investigated systematically. It can be concluded that the 9 wt% human hair can be complete dissolved in [Emim]DEP at 130 degrees C for 90 min, and the dissolution capability of [Emim]DEP after 5 recycles is same as the fresh [Emim]DEP. The structure of regenerated keratin was characterized by FT-IR, XRD and TGA, and the results indicated that the structure of regenerated keratin is similar with the human hair. (C) 2021 Elsevier B.V. All rights reserved