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

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