Quaternized carboxymethyl chitosan/organic montmorillonite nanocomposite as a novel cosmetic ingredient against skin aging.

It is of technical and economic importance to develop an effective cosmetic ingredient against skin aging through low-cost and facile production. This study developed a polymer/layered silicate nanocomposite as cosmetic ingredient against skin aging. Firstly, quaternized carboxymethyl chitosan (QCMC)/organic montmorillonite (OMMT) nanocomposite (QCOM) was fabricated via solution-induced intercalation. QCOM with different mass ratios of QCMC to OMMT were studied by various characterizations as well as moisture-adsorption and retention activities and UV-protection capacity. QCOM was then added into a cosmetic formulation to prepare a cosmetic cream. And the evaluation of its efficacy about skin care was conducted. The results showed that the optimal QCOM had better moisture-adsorption and retention behaviors than hyaluronic acid, and QCOM solution displayed good UV-protection ability. Furthermore, the QCOM-containing cosmetic cream meets the hygienic standard for cosmetics; it has negligible dermal irritation and a prominent moisture-retention efficacy on human stratum corneum.