Engineering Eutectogel Microneedle Patch as Effective Transdermal Delivery System of Hydrophobic Drugs

Conventional drug delivery methods often face challenges in terms of patient adherence and drug administration. Microneedles (MNs) patches have emerged as a promising alternative, offering a minimally invasive transdermal route for medications. However, their drug-loading capacity remains limited, particularly for hydrophobic active pharmaceutical ingredients (APIs). Herein, microneedles are designed based on eutectic solvent gels (eutectogels) as transdermal carriers for hydrophobic APIs. A natural deep eutectic solvent (NADES) is combined to enhance the solubility of the hydrophobic APIs within the GelMA/PEGDA matrix for mechanical strength and sustained release from the resulting eutectogels microneedles (EU-MNs). Using docetaxel, 5-fluorouracil, and curcumin as hydrophobic APIs models, the superior drug-loading capacity of the EU-MNs is demonstrated. In vitro experiments revealed that the EU-MNs provided a sustained release of distinct hydrophobic APIs over 4 days. Additionally, by properly adjusting the concentration and type of APIs, these microneedle patches do not exhibit cytotoxic effects on fibroblasts cell line (NIH/3T3), underscoring their potential for safe and effective transdermal drug delivery. These findings highlight the potential of EU-MNs as versatile, eco-friendly transdermal vehicles for large amounts of hydrophobic APIs, leading to more effective treatments for these drugs.