Hydroxyapatite-embedded levan composite hydrogel as an injectable dermal filler for considerable enhancement of biological efficacy

Abstract

We previously developed an injectable levan-based hydrogel as a temporary dermal filler. However, the longevity and collagen stimulation effect of the levan-based hydrogel were limited. Herein, we prepared hydroxyapatite (HAp)-embedded levan composite hydrogel as a long-acting dermal filler for enhancing in vivo collagen production and anti-wrinkle efficacy. HAp amount (0.1-5 wt%) in the levan hydrogel was optimized for stability, safety, and efficacy. Increasing the HAp amount decreased the in vitro stability and elastic modulus, but the composite hydrogel structure was still maintained. Furthermore, the composite hydrogel showed improved cell proliferation stimulation compared to the bare levan hydrogel in human dermal fibroblast cells. In vivo stability of the composite hydrogel was enhanced in contrast to the in vitro result, showing stable residence of the composite hydrogels with 0.5 or 1 wt% HAp over 8 weeks. Moreover, the excellent anti-wrinkle efficacy of composite hydrogel with 1 wt% HAp was maintained during 8 weeks and it showed the highest collagen production. Thus, HAp-embedded levan composite hydrogel showed potential as a dermal filler with easy injectability, biocompatibility, and long acting anti-wrinkle efficacy. (c) 2021 The Korean Society of Industrial and Engineering Chemistry. Published by Elsevier B.V. All rights reserved.