Bio-inspired microneedle design for efficient drug/vaccine coating

Abstract

AbstractBiomimetics is the interdisciplinary scientific field focused on the study and imitation of biological systems, with the aim of solving complex technological problems. In this paper, we present a new bio-inspired design for microneedles (MNs) and MN arrays, intended for rapidly coating the MNs with drug/vaccine. The biomimetic approach consists in ornamenting the lateral sides of pyramidal MNs with structures inspired by the external scent efferent systems of some European true bugs, which facilitate a directional liquid transport. To realize these MNs, two-photon polymerization (TPP) technique was used. Liquid coating capabilities of structured and non-structured MNs were compared. Moreover, both in-vivo and ex-vivo skin tests were performed to prove that MNs pierce the skin. We show that the arrays of MNs can be accurately replicated using a micro-moulding technique. We believe this design will be beneficial for the process of drug/vaccine loading onto the needles’ surfaces, by making it more efficient and by reducing the drug/vaccine wastage during MN coating process.