Coated 3D Printed PLA Microneedles as Transdermal Drug Delivery Systems

摘要

Microneedles facilitate transdermal drug delivery by piercing microscale pores through the stratum corneum. They usually penetrate only thought the stratum corneum thus the nociceptors of the skin will not be stimulated. Therefore, as an alternative approach, microneedles provide a minimally invasive method for drug delivery. Additive manufacturing which is called threedimensional (3D) printing revolutionized the field of pharmaceutical and biomedical sciences due to their capabilities for fast and cost-effective prototyping of complex structures. Biodegradable 3D printed PLA microneedles are an emerging class of novel transdermal drug delivery systems. Aims of this study were to fabricate 3D printed microneedles and investigate for the first time the ability to coat different drug formulations on 3D printed microneedles. We demonstrated that 3D printing combined with the post-fabrication etching step could make ideally sized and shaped microneedles. Dip coating method revealed to be the best coating method for 3D printed microneedles because of its simplicity and ability to create a uniform load over the printed microneedles. We have also shown that 3D printed microneedles could successfully penetrate and break off into porcine skin.