ARC Centre of Excellence in Convergent Bio-Nano Science and Technology, and the Department of Chemical Engineering, The University of Melbourne, Parkville, Victoria, 3010, Australia.
Micro/Nanophysics Research Laboratory, School of Engineering, RMIT University, Melbourne, Victoria, 3000, Australia.
Adv Mater. 2021 Apr;33(13):e2006177. doi: 10.1002/adma.202006177. Epub 2021 Feb 26.
Light-driven directional motion is common in nature but remains a challenge for synthetic microparticles, particularly regarding collective motion on a macroscopic scale. Successfully engineering microparticles with light-driven collective motion could lead to breakthroughs in drug delivery, contaminant sensing, environmental remediation, and artificial life. Herein, metal-phenolic particle microswimmers capable of autonomously sensing and swimming toward an external light source are reported, with the speed regulated by the wavelength and intensity of illumination. These microswimmers can travel macroscopic distances (centimeters) and can remain illuminated for hours without degradation of motility. Experimental and theoretical analyses demonstrate that motion is generated through chemical transformations of the organic component of the metal-phenolic complex. Furthermore, cargos with specific spectral absorption profiles can be loaded into the particles and endow the particle microswimmers with activated motion corresponding to these spectral characteristics. The programmable nature of the light navigation, tunable size of the particles, and versatility of cargo loading demonstrate the versatility of these metal-phenolic particle microswimmers.
光驱动的定向运动在自然界中很常见，但对于合成微粒子来说仍然是一个挑战，特别是在宏观尺度上的集体运动方面。成功地设计出具有光驱动集体运动的微粒子，可以在药物输送、污染物感应、环境修复和人工生命等领域取得突破。本文报道了一种能够自主感应并朝着外部光源游动的金属-酚粒子微游泳者，其速度可以通过光照的波长和强度来调节。这些微游泳者可以行进宏观距离（厘米级），并且在没有运动能力下降的情况下可以持续光照数小时。实验和理论分析表明，运动是通过金属-酚配合物中有机成分的化学转化产生的。此外，可以将具有特定光谱吸收特征的货物装入粒子中，并赋予粒子微游泳者与这些光谱特征相对应的激活运动。光导航的可编程性、粒子的可调尺寸以及货物装载的多功能性，展示了这些金属-酚粒子微游泳者的多功能性。
