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Abstract Controllable and long‐term release remains a great challenge in current drug delivery systems. Benefiting from their efficient drug loading and painless administration, microneedles (MNs) have emerged as a promising platform for transdermal drug delivery, while they often fail to achieve long‐term tissue adhesion and controllable extended drug release. Here, 3D printing of an innovative MN patch is presented with succulent‐inspired responsive microstructures and light‐controllable long‐term release capability. The MN exhibits a reversible shrink‐swell volume change behavior in response to surrounding humidity, which enables sufficient mechanical strength for skin penetration under the shrinkage conditions and efficient long‐term adhesion when swollen in skin tissues. Moreover, the MN patch introduces a controllable long‐term drug release system, achieved through the integration of thiolated heparin (Hep‐SH) for sustained growth factor release and graphene oxide (GO) nanosheets for controlled drug release via near infrared (NIR) laser irradiation. The MN patches with growth factor loading have good biocompatibility and can promote the proliferation, migration, and proangiogenesis of endothelial cells is further demonstrated. Thus, it is believed that such flexible MN patches can be promising candidates for controllable long‐term transdermal drug delivery as well as other related tissue engineering applications.
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This content will become publicly available on February 9, 2026
Engineering Eutectogel Microneedle Patch as Effective Transdermal Delivery System of Hydrophobic Drugs
Abstract 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.
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- PAR ID:
- 10571460
- Publisher / Repository:
- Wiley Blackwell (John Wiley & Sons)
- Date Published:
- Journal Name:
- Advanced Therapeutics
- Volume:
- 8
- Issue:
- 5
- ISSN:
- 2366-3987
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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