Shape-Transformable, Fusible Rodlike Swimming Liquid Metal Nanomachine

Abstract

The T-1000 liquid metal terminator, which can transform and self-repair, represents a dream for decades that robots can fundamentally change our daily life. Until now, some large-scale liquid metal machines have been developed. However, there is no report on nanoscaled liquid metal machines and their biomedical applications. We describe here a shape-transformable and fusible rodlike swimming liquid metal nanomachine, based on the biocompatible and transformable liquid metal gallium. These nanomachines were prepared by a pressure-filter-template technology, and the diameter and length could be controlled by adjusting the nanoporous templates, filter time, and pressure. The as-prepared liquid gallium nanomotors display a core-shell nanorod structure composed of a liquid gallium core and solid gallium oxide shell. Upon exposure to an ultrasound field, the generated acoustic radiation force in the levitation plane can propel them to move autonomously. The liquid metal nanomachine can actively seek cancer cells and transform from a rod to a droplet after drilling into cells owing to the removal of gallium oxide layers in the acidic endosomes. These transformed nanomachines could fuse together inside cells and photothermally kill cancer cells under illumination of near-infrared light. Such acoustically propelled shape-transformable rodlike liquid metal nanomachines have great potential for biomedical applications.

Recent Advances in Nano‐ and Micromotors

“…Their self‐propulsion took advantage of the amplitude of the flagellar oscillation induced by an external acoustic field ( Figure A‐i), which enabled control over the micromotor's speed (Figure A‐ii) . Similarly, shape‐transformable nanomachines made of gallium were reported to self‐propel when exposed to an ultrasound field . The micromotors were synthesized by a pressure‐filter‐template method and displayed a rod‐like shape of around 1 cm (Figures B‐i,ii).…”

Liquid Metal–Based Soft Microfluidics

“…e) Photothermal treatment of the cancer cell by NIR laser irradiation. Reproduced with permission . Copyright 2018, American Chemical Society.…”

Ga‐Based Liquid Metal Micro/Nanoparticles: Recent Advances and Applications

“…The shape‐transformable and photothermal properties of LMPs could be used as a nanomachine for a medical application. Wang et al synthesized rod shape Ga particles and reported that the particles entered cancer cells through a self‐propelled swim driven by an acoustic radiation force. The injected Ga rods underwent fusion to Ga spheres due to the removal of Ga oxide shell and the Ga spheres killed the cancer cell by photothermal effect under near‐IR light illumination.…”