Near-infrared Triggered Biodegradable Microneedle Patch for Controlled Macromolecule Drug Release.

Transdermal drug delivery of macromolecule drugs has attracted significant attention due to the advantage of convenience and biocompatibility. However, the practical usage of it is limited by the low delivery efficiency and poor drug absorption. To develop an efficient, safe, and controllable transdermal delivery method, the near-infrared (NIR) triggered calcium sulfate and gelatin biodegradable composite microneedle (MN) patches have been developed. The MN patches were fabricated by polydimethylsiloxane (PDMS) molds, and the structure data could be adjusted by changing the molds. Such an MN patch could release both macro and micro molecule drugs. After loaded with photothermal converter IR780, which could transfer energy of light to heat, the release of macromolecule drugs in MNs could be controlled by applying NIR irradiation. The control effect could be enhanced by spraying 1-tetradecanol (TD) coating and optimizing the ratio (weight) of gelatin and calcium sulfate to 2:6. Besides, the MN patch could deliver drugs through the skin barrier, and the process could be controlled by NIR. Moreover, the insulin-loaded MN patch exhibits some therapeutic effects on healthy mice. This work suggests that biodegradable MNs could achieve controllable drug delivery and potentially be applied in individual treatment via transdermal ingestion. This article is protected by copyright. All rights reserved.