A Comprehensive Design-to-skin Pipeline to Fabricate Polymeric Microneedles Using Ultrahigh-resolution 3D Printing

OBJECTIVE: Microneedle technologies have emerged as a promising approach to improve intradermal drug delivery. This study presents a comprehensive workflow for fabricating polymeric microneedle arrays utilising ultrahigh-resolution 3-dimensional (3D) printing and silicone mould fabrication. METHODS: In this work, an extensive toolbox with over 75 distinct microneedle designs was created and sequentially fabricated from acryl using our workflow based on ultrahigh-resolution 3D printing. RESULTS: The microneedle design parameters included obelisk and cone-like shapes, various lengths, base and tip diameters, and different densities. We systematically assessed the optimal design parameters for effective penetration of ex vivo human skin explants. CONCLUSION: Our workflow, combined with application in an ex vivo human skin model, allows systematic comparison of multiple microneedle design parameters for efficacy. This work demonstrates the potential of this systematic modelling and ultrahigh-resolution 3D printing approach to optimize microneedles for intradermal biomedical applications, including therapeutic cancer vaccination.