Hyaluronic acid-hydroxyapatite nanocomposite hydrogels for enhanced biophysical and biological performance in a dermal matrix.

A hyaluronic acid (HAc)-hydroxyapatite (HAp) nanocomposite (HAc-nanoHAp) hydrogel was fabricated through an in situ precipitation process for mechanical and biological enhancement as a soft tissue augmentation product. In this study, these composite hydrogel fillers were analyzed from three different perspectives and compared with pure HAc hydrogel for soft tissue augmentation application: (1) rheological behaviors, (2) in vivo lateral diffusion under mouse skin, and (3) wrinkle improvement in a photo-aged mouse model. HAc-nanoHAp provided great improvement to wrinkles because of its higher stiffness and gel cohesiveness in comparison with that of pure HAc. HAc-nanoHAp also presented great enhancement in strengthening the dermal matrix by stimulating the synthesis of collagen and elastin. Thus, HAc-nanoHAp filler has great potential as a soft tissue augmentation product, improving the biophysical and biological performance in skin tissue.