OBJECTIVE  To prepare soluble microneedles loaded with gastrodin, and to investigate their physical and chemical properties and transdermal properties in vitro.

  METHODS  The soluble microneedles loaded with gastrodin were prepared by two-step centrifugation method, and the drug loading was determined by HPLC. Morphology, mechanical properties, skin puncture performance and recovery performance were investigated. The in vitro transdermal properties were investigated by Franz diffusion cell.

  RESULTS  The prepared microneedles had complete array, good flexibility and good mechanical properties. The drug loading of each tablet was up to (5.45±0.14)mg, and the skin could be successfully penetrated. The skin could be restored to its original state within 2 h after the treatment. In vitro skin infiltration results showed that the cumulative osmotic amount of gastrodin in the fully loaded microneedles reached 87% after 12 h, while the cumulative osmotic amount of gastrodin in the gastrodin solution was 12%, indicating that the soluble micro-target gastrodin had a good promoting effect on transdermal delivery of gastrodin.

  CONCLUSION  The soluble microneedles prepared in this study have good mechanical strength and flexibility, and can realize transdermal delivery of water-soluble drugs.