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

The study introduces a finite element analysis (FEA)-guided co-design framework for developing separable bubble microneedles (BMNs) that optimize geometry and cavity parameters for controlled tip separation and robust insertion. The research demonstrated that minoxidil sulfate-loaded BMNs (MXS-BMNs) and insulin-loaded BMNs (INS-BMNs) achieved effective transdermal and sublingual delivery, respectively, with separation forces closely matching FEA predictions and axial strengths surpassing skin and mucosa penetration thresholds. In vivo tests showed MXS-BMNs significantly enhanced hair regrowth in mice, while INS-BMNs effectively lowered glucose levels in diabetic rats. This approach reduces empirical iteration, facilitating the rapid development of efficient microneedle systems for drug delivery.