Preparation and characterization of dissolving hyaluronic acid composite microneedles loaded micelles for delivery of curcumin.

In order to improve the bioavailability of curcumin (Cur) and patient compliance, a type of novel hyaluronic acid (HA) composite microneedles containing Cur-loaded micelles was designed in this paper. On the one hand, the microneedles matrix solution was prepared by screening the optimal concentration of HA and the better proportion of HA to sodium carboxymethyl starch (CMS-Na). On the other hand, the amphiphilic polymer, named as Quercetin-Dithiodipropionic Acid-Oligomeric Hyaluronic Acid (Que-DA-oHA), was synthesized and characterized using 1H-NMR. Subsequently, the dialysis method was used to prepare Cur-loaded Que-DA-oHA micelles with an average size of 172.6 ± 11.4 nm and zeta potential of - 33.71 ± 0.45 mV. A micromolding process was used to prepare the micelle-loaded HA composite microneedles. It had been found that when the concentration of HA was 200 mg/mL and the mass ratio of HA to CMS-Na was 2:1, the prepared HA composite microneedles had good mechanical strength. In-skin dissolution kinetics showed that the micelle-loaded HA composite microneedles could dissolve quickly in the skin. In vitro permeation study indicated that the microneedles delivered 74.7% of their drug load over 6 h, which exhibited remarkable drug permeation properties in a short time. Here, we creatively combined micellar technology with microneedle technology to rapidly deliver Cur transdermally for diseases treatment such as melanoma. Graphical abstract.