Engineering Active Micro and Nanomotors

Abstract

Micro- and nanomotors (MNMs) are micro/nanoparticles that can perform autonomous motion in complex fluids driven by different power sources. They have been attracting increasing attention due to their great potential in a variety of applications ranging from environmental science to biomedical engineering. Over the past decades, this field has evolved rapidly, with many significant innovations contributed by global researchers. In this review, we first briefly overview the methods used to propel motors and then present the main strategies used to design proper MNMs. Next, we highlight recent fascinating applications of MNMs in two examplary fields, water remediation and biomedical microrobots, and conclude this review with a brief discussion of challenges in the field.

Acoustic Propulsion of Nano- and Microcones: Dependence on the Viscosity of the Surrounding Fluid

“…After the idea of nano- and micromachines that carry out medical tasks inside a patient’s body has been a dream for several decades, the progress in nanotechnology at the end of the last century made the fabrication of motile nano- and microparticles (so-called active particles) possible. − During the last two decades, a large number of artificial motile nano- and microparticles that utilize various mechanisms for propulsion have been developed, ,− and fascinating future applications of these particles have been envisaged in fields like medicine, − where they could be used for targeted drug delivery, − materials science, − where they could be used to form active crystals − and other new types of matter, and environmental care. ,− …”

Armoring a liposome-integrated tissue factor with sacrificial CaCO3 to form potent self-propelled hemostats

“…Calcium carbonate (CaCO 3 ) is a simple, self-propelling particle system capable of mineralizing a cargo and delivering it through flowing aqueous solution via acid-induced CO 2 bubble generation. [21][22][23] In our previous work, we developed CaCO 3 -mineralized nanoparticles from liposomes rich in carboxyl/phosphate groups, similar to the method used to reconstitute the TF in vitro for full procoagulant activity. 9,24 One appealing aspect we found was that the CaCO 3 precursor initially formed liquid droplets around the liposomes, and then transformed into an amorphous CaCO 3 (ACC) coating via dehydration, in favor of maintaining the integrity of the occluded liposomes.…”

Bridging the gap: harnessing liquid nanomachine know-how for tackling harmful airborne particulates

“…[6][7][8] Some common types of nanomachines include Janus spheres, nanowires, microjets and particles with chiral structures. 9 Versatile methods of nanomachines' external control have been demonstrated using ultrasound, 10 electrochemical potential, 11 oscillating electric (AC) field, 12 magnetic field, 13 light, 14 and chemotaxis, 15 to name a few examples. Some prominent fields of nanomachine applications are medicine, environmental science, and energy.…”