Production and <i>Ex Vivo</i> Characterization of Melting Lipid Needle Patches Applied for Transdermal Delivery of Lipophilic Drugs

Microneedle patches have gained significant attention for transdermal drug delivery, particularly those made from hydrophilic polymers for hydrophilic drugs. However, delivering poorly water-soluble lipophilic drugs remains a challenge. Our study introduces a lipid-based microneedle patch capable of effectively delivering lipophilic drugs with mechanically robust needles that penetrate physiological barriers like skin. Using a high-yield melt casting method, we produced needles up to 1200 μm in length with tunable melting points and phase transitions by adjusting lipid compositions. These patches release drugs at body temperature (37 °C). In a proof-of-concept experiment, curcumin, a model lipophilic drug, was fully dissolved and uniformly distributed in the needles, with drug loadings up to 50 wt %. Ex vivo studies demonstrated successful needle penetration and drug release in porcine skin. This lipid-based microneedle platform offers an effective solution for the transdermal, transmucosal, and buccal delivery of lipophilic drugs.