4D Printing of a Bioinspired Microneedle Array with Backward-Facing Barbs for Enhanced Tissue Adhesion
4D Printing of a Bioinspired Microneedle Array with Backward-Facing Barbs for Enhanced Tissue Adhesion
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DOI：
10.1002/adfm.201909197
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发表时间：
2020-02-04
影响因子：
19
通讯作者：
Lee, Howon
中科院分区：
文献类型：
--
作者：
Han, Daehoon;Morde, Riddish S.;Lee, Howon
微针（MN）是一种长度为数百微米的微型针，由于其微创、无痛和易于使用的特性而受到极大的关注。然而，使用MN的受控长期药物递送或生物传感的主要挑战是其低组织粘附性。尽管具有高组织粘附性的微观结构是从自然界中的活生物中发现的（例如，寄生虫的微钩、蜜蜂的带刺刺、豪猪的刺），但是用传统的制造方法制造具有这种复杂的微观特征的MN仍然具有挑战性。在这里，呈现了通过数字光处理3D打印技术制造的MN，其具有生物启发的面向后的弯曲倒钩，用于增强组织粘附。MN上的面向后的倒钩通过利用光固化聚合物中的交联密度梯度的去溶剂化诱导的变形来产生。倒钩厚度和弯曲曲率由印刷参数和材料成分控制。结果表明，向后倒钩MN的组织粘附力是无倒钩MN的18倍。还证明了在组织中使用倒刺MN的持续药物释放。生物启发MN的改善的组织粘附允许药物递送、生物流体收集和生物感测的更稳定和稳健的性能。
Microneedle (MN), a miniaturized needle with a length-scale of hundreds of micrometers, has received a great deal of attention because of its minimally invasive, pain-free, and easy-to-use nature. However, a major challenge for controlled long-term drug delivery or biosensing using MN is its low tissue adhesion. Although microscopic structures with high tissue adhesion are found from living creatures in nature (e.g., microhooks of parasites, barbed stingers of honeybees, quills of porcupines), creating MNs with such complex microscopic features is still challenging with traditional fabrication methods. Here, a MN with bioinspired backward-facing curved barbs for enhanced tissue adhesion, manufactured by a digital light processing 3D printing technique, is presented. Backward-facing barbs on a MN are created by desolvation-induced deformation utilizing cross-linking density gradient in a photocurable polymer. Barb thickness and bending curvature are controlled by printing parameters and material composition. It is demonstrated that tissue adhesion of a backward-facing barbed MN is 18 times stronger than that of barbless MN. Also demonstrated is sustained drug release with barbed MNs in tissue. Improved tissue adhesion of the bioinspired MN allows for more stable and robust performance for drug delivery, biofluid collection, and biosensing.