Application of Cross-Linked and Non-Cross-Linked Hyaluronic Acid Nano-Needles in Cosmetic Surgery.

The common feature of non-cross-linked hyaluronic acid nano-needles is that they penetrate the skin and dissolve rapidly, and the non-cross-linked hyaluronic acid will migrate under the skin, so it is difficult to maintain the long-term expansion effect in a fixed position. In order to achieve the relatively long-term antiwrinkle effect, a kind of cross-linked and non-cross-linked compound hyaluronic acid microne was prepared. By inserting the microne under the skin, dissolving the non-cross-linked part under the skin and introducing the cross-linked gel particles under the skin, the effect of extending the microne was achieved. The mechanical properties, permeability, and degradation rate of cross-linked and non-cross-linked hyaluronic acid composite nano-needles were studied in detail. Experimental results show that the higher the content of CHA, the slower the degradation rate of the microneedle, and the skin swelling of the HA_CHA (1 : 1) microneedle is the most lasting. With the increase of CHA content in microneedle matrix materials, the degree of epidermal expansion decreased. The preparation of cross-linked and non-cross-linked hyaluronic acid microneedles has the potential to be effectively used as dermal fillers in cosmetics or antiaging treatments.