Cu-Fe bimetallic nanozyme@halloysite-sodium alginate composite hydrogel for the treatment of atopic dermatitis

Atopic dermatitis is a typical chronic inflammatory disease with pathological characteristics of persistent immune activation and oxidative stress. The combined anti-inflammatory and antioxidant treatment can effectively block the inflammatory cascade while reducing oxidative damage. Halloysite nanotubes (HNTs) are the main component of the traditional Chinese medicine "Chishizhi", which shows the medicinal functions of astringency, hemostasis and astringency. However, the efficacy of HNTs alone in treating diseases is relatively weak, and its therapeutic effect can be improved by surface modification and drug loading. Herein, CuO-Fe3O4 nanoparticles were synthesized on the outer surfaces of HNTs by hydrothermal reaction. CuO-Fe3O4@HNTs has high SOD and CAT enzyme activities under neutral condition. Then, the nanozyme modified HNTs powder was prepared into sprayable hydrogels by introduction of sodium alginate (SA) and aloe vera extracts. Cell experiments confirmed that the hydrogel can promote HacaT cell proliferation within 0~200 μg/mL concentration. Through the mouse animal dermatitis model, CuO-Fe3O4@HNTs-SA composite hydrogel has a good therapeutic effect on atopic dermatitis. Comparing with the positive drug halcinonide solution, the CuO-Fe3O4 nanozymes incorporated hydrogel showed enhanced therapeutic effect, which shows promising prospects in the clinical treatment of atopic dermatitis.