Structural evaluation by the finite element method of hollow microneedle geometries for drug delivery

Abstract

Herein, the structural comparison, using thefinite-element method (FEM), ofdifferent designs of individual hollow microneedles (MNs) is exposed, that is,conical, pyramidal, traditional, and sting type, for use as a transdermal drugdelivery system (TDDS). These configurations attract interest infields such aspharmaceutics and medicine due to their efficiency, easy administration of drugs,and significant reduction in pain compared to the traditional use of hypodermicneedles. For the structural analysis and comparison of the proposed designs,ANSYS FEM-based software is used to simulate the insertion of an MN in theskin. The study and comparison are carried out under simulations of structuralresistance, buckling analysis, and behavior in the MN–skin contact. The appli-cation forces are set according to the fracture resistance of the outside layer of theskin. A force of 0.16N for a conical MN isfinally obtained as a critical applicationload to avoid a structural failure in the insertion of the MN in the human skin.Moreover, the use of poly(lactic-co-glycolic) acid (PLGA) is also assessed as asecond biocompatible alternative due to both its easy handling for manufactureprocess and the resistance it presents in indentation simulations in which theapplied force reaches 0.19N.RESEARCH ARTICLEwww.aem-journal.comAdv. Eng. Mater.2022, 22000492200049 (1 of 7)© 2022 Wiley-VCH GmbH