Multi-scale Nanotextured Surfaces by Tribo-Electrohydrodynamic Lithography for Controlled Drug Release

该基金支持为快速制造多尺度纳米结构创造颠覆性纳米制造技术的研究，促进科学进步，促进国家繁荣和健康。利用现有的纳米加工方法实现多尺度纳米结构是一项具有挑战性的工作。例如，电子束光刻仅限于非常小的尺度结构，而纳米压印光刻需要非常精细的主图案。该项目探索了纳米级复制成型技术，作为一种快速而廉价的方式，从大面积模板中形成复杂的主纳米结构。利用表面“摩擦荷”的形成制备了具有亚100纳米亚结构的多尺度纳米结构。通过这种方法，具有生物医学用途的纳米纹理表面是可能的。通过详细的计划来刺激纳米制造，并将由此产生的表面图案生物医学设备带给心脏病患者，这项工作与国家促进美国制造业和创新生物医学技术的努力是一致的。这项研究涉及多个学科，包括制造、表面物理、电磁学和材料科学。这种多学科的方法有助于扩大妇女和代表性不足的少数民族在研究中的参与，并对工程教育产生积极影响。该项目通过纳米级复制成型实现了对聚合物基板上摩擦电荷分布的高度控制的纳米模式，并对摩擦电荷的产生和模式的潜在机制有了更深入的了解。对摩擦电荷的寿命、空间稳定性和纳米纹理依赖性进行了研究。然后将纳米图案摩擦荷用作电流体动力光刻的纳米调制电场源，通过该电场制备3级分层多尺度纳米结构。目标纳米结构包括亚100纳米尺度的纳米火山和多周期纳米结构阵列。这种由生物相容性聚合物制成的多尺度纳米结构的药物释放也被研究用于心脏治疗支架等新兴应用。基础研究成果拓宽了实现多尺度纳米结构所需的知识，最终使具有新功能的新材料和结构的合成成为可能。该奖项反映了美国国家科学基金会的法定使命，并通过使用基金会的知识价值和更广泛的影响审查标准进行评估，被认为值得支持。

This grant supports research that creates a disruptive nanoscale manufacturing technology for rapid fabrication of multiscale nanostructures, promotes scientific progress, and advances national prosperity and health. Realization of multiscale nanostructures with existing nanofabrication methods is a challenging endeavor. For example, electron beam lithography is limited to very small scale structures, whereas nanoimprint lithography requires very elaborate master patterns. This project explores the technique of nanoscale replica molding as a rapid and inexpensive way to form intricate master nanostructures from large-area templates. The accompanying formation of surface "tribocharges" are utilized to fabricate multiscale nanostructures with sub-100 nanometer sub-structures. By this means, nanotextured surfaces having biomedical uses are possible. With elaborate plans to stimulate nanomanufacturing and bring the resulting surface-patterned biomedical devices to the people with heart-disease, this work aligns well with the nation's efforts to boost manufacturing in the U.S. and to innovate biomedical technologies. This research involves several disciplines including manufacturing, surface physics, electromagnetics, and materials science. This multi-disciplinary approach helps broaden the participation of women and underrepresented minorities in research and positively impacts engineering education.This project enables highly controlled nanopatterning of tribocharge distribution on polymer substrates through nanoscale replica molding and provides a deeper understanding of the underlying mechanisms for generation and patterning of tribocharges. Investigations of the tribocharge's longevity, spatial stability, and nanotexture dependence are performed. The nanopatterned tribocharges are then used as the source of nanoscale-modulated electric fields for electrohydrodynamic lithography, by which 3-level hierarchical multiscale nanostructures are fabricated. The target nanostructures include nanoscale volcanoes with sub-100 nm-scale nanocraters and multiple-period nanostructure arrays. The drug release from such multiscale nanotextures made of biocompatible polymers are also studied for emerging applications such as stents for cardiac therapies. The fundamental research outcomes widen the knowledge required for the realization of multiscale nanostructures in general, eventually enabling the synthesis of new materials and structures with novel functionalities.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.