Preparation and Evaluation of a Soluble Microneedle Loaded with Resveratrol Nanocrystals

Resveratrol has a variety of pharmacological activities, but it is not widely used clinically because of its poor water solubility and low bioavailability. Changing the dosage form of resveratrol to improve its solubility and utilization is a key element to enhance the clinical application of resveratrol. Soluble microneedle-loaded nanocrystals prepared with low molecular sodium hyaluronate by vacuum method can solve the problems of low solubility and low bioavailability of resveratrol, and at the same time, it can achieve the effect of prolonging the duration of drug action. Methods: Resveratrol nanocrystals were prepared using the micro-media milling method, and the experimental conditions, such as the type of stabilizer, the ratio of stabilizer to drug, the dosage of milling beads, and the milling time were screened using the nanocrystal particle size as well as the dispersion degree as the indexes, so as to determine the optimal preparation process and carry out a series of characterizations. The dissolvable microneedles of sodium hyaluronate prepared by vacuum method were examined for morphology, skin puncture performance and skin dissolution performance to determine the optimal preparation method. RESULTS: The resveratrol nanocrystals prepared by the optimal process had a small particle size of around 100 nm, good stability, and good release characteristics as seen in the in vitro release experiments. The low molecular sodium hyaluronate soluble microneedles loaded with resveratrol nanocrystals had a good morphology and a full and uniform tip, with good skin puncture performance and skin dissolution performance. Conclusion: The prescription process was determined through several tests, and the quality evaluation determined that the resveratrol nanocrystals were good, indicating that good resveratrol nanocrystals could be produced by micro-media milling, and that it was feasible to use hyaluronic acid-prepared microneedles piggybacked with resveratrol nanocrystals to improve their bioavailability.