Fig. 7. Microneedle array fabrication development by 2PP.

a SEM of multiple designs of a single microneedle and arrays of microneedles with open-channel designs connected to microfluidic reservoirs. Microneedles have a 700 μm height and a flange design at the base with a 150 μm height. b Multiphoton microscopy image representing the diffusion of fluorescein solution underneath the skin surface of a rabbit ear (top-right image) and the topical application of solution on the tissue surface as a control (top-left image) after insertion of an array of 16 microneedles¹¹. Reprinted from ref. ¹¹ with permission. c Manufacturing steps for producing dissolving microneedles loaded with different drugs, including cabotegravir sodium and ibuprofen sodium¹⁷. Reprinted from ref. ¹⁷ with permission.