FEA-Guided Co-Design of Bubble Microneedles: Controlled Tip Separation for Rapid Transdermal and Sublingual Delivery

This study introduces a finite element analysis (FEA)-guided framework for designing separable bubble microneedles (BMNs) that optimize geometry and cavity parameters for controlled tip separation and robust insertion. The study tested minoxidil sulfate-loaded BMNs (MXS-BMNs) and insulin-loaded BMNs (INS-BMNs) for transdermal and sublingual delivery, respectively. The BMNs demonstrated effective payload release, with over 80% liberated within 10 minutes. In ex vivo tests, MXS-BMNs showed significantly higher minoxidil permeation compared to topical gel, and in vivo tests on mice showed accelerated hair regrowth. INS-BMNs effectively lowered glucose levels in diabetic rats, comparable to subcutaneous injections. This approach reduces empirical iteration, facilitating the development of efficient microneedle systems for rapid drug delivery.