Recent development and advances on fabrication and biomedical applications of Ga-based liquid metal micro/nanoparticles

Liquid metals (LMs), as special kind of metals, have been extensively applied in many fields, including electronics, mechanical engineering, and energy etc. Among these LMs, Ga-based LMs should be one of the most promising ones for biomedical applications since its outstanding physicochemical properties, such as weak binding energy between Gallium (Ga) atom, easy surface modification, excellent photothermal conversion efficiency and low toxicity. However, direct utilization of bulk Ga-based LMs for biomedical applications is of some issues and strategies for fabrication of Ga-based functional nanocomposites have been developed over the past several years. These strategies could not only break down Ga-based LMs into nanoscale size, but also endow new functions during formation of Ga-based composites. It opens a new avenue for the biomedical applications of these Ga-based multifunctional nanoparticles (NPs). Although the biomedical applications of Ga-based LMs have attracted increasing research attention and great advances have been made over the past decade, none of them are focused on the fabrication and surface functionalization of Ga-based NPs. In this review, the main context can be majorly divided into two sections. In the first part, the top-down methods as well as the surface functionalization of Ga-based NPs, including FRP, ATRP, RAFT, electrochemical displacement, ring opening polymerization etc. were introduced. In the following section, the biomedical applications of liquid metal nanoparticles (LMNPs) such as drug delivery, treatment of infectious diseases, cancer and imaging were outlined. We trust this review article will attract great interest for the scientists from chemistry, materials, biological and medical fields.