Transformable liquid-metal nanomedicine

Abstract

To date, numerous inorganic nanocarriers have been explored for drug delivery systems (DDSs). However, the clinical application of inorganic formulations has often been hindered by their toxicity and failure to biodegrade. We describe here a transformable liquid-metal nanomedicine, based on a core–shell nanosphere composed of a liquid-phase eutectic gallium-indium core and a thiolated polymeric shell. This formulation can be simply produced through a sonication-mediated method with bioconjugation flexibility. The resulting nanoparticles loaded with doxorubicin (Dox) have an average diameter of 107 nm and demonstrate the capability to fuse and subsequently degrade under a mildly acidic condition, which facilitates release of Dox in acidic endosomes after cellular internalization. Equipped with hyaluronic acid, a tumour-targeting ligand, this formulation displays enhanced chemotherapeutic inhibition towards the xenograft tumour-bearing mice. This liquid metal-based DDS with fusible and degradable behaviour under physiological conditions provides a new strategy for engineering theranostic agents with low toxicity.

Recent progress on liquid metals and their applications

“…Chemical passivation is an intrinsic property of Ga that enables Ga and Ga-based alloys to be used as dielectrics, although it also hinders their general use as liquid conductors. The surfaces of pure Ga or eutectic Ga-based alloys are easily oxidised and form an amorphous Ga oxide layer in the ambient environment that decreases the surface tension of the liquid metal [11][12][13]. The thickness of the intrinsically formed Ga oxide surface layer is 0.5-3 nm [14][15][16].…”

“…These approaches are limited by certain factors, however, such as toxicity and lack of biodegradability [12]. Lu et al reported a method to use Ga-based liquid metal nanoparticles for drug delivery, owing to the low toxicity of Ga and its alloys [12,104]. They use EGaIn-based drug nanocarriers that are assembled with thiolated ligands on the surfaces of these nanoparticles through ultrasonication around room temperature.…”

Congratulations to the 2016 JALA Ten!

“…Terminating Cancer with LiquidMetal-Based Drug Delivery Systems 10 While the use of inorganic nanomaterials in drug delivery remains an area of active research in nanomedicine, clinical translation of inorganic material-based drug delivery systems has been difficult due to their toxicity and clearance failures. A promising new approach that overcomes these hurdles was developed by Zhen Gu and his team at the University of North Carolina at Chapel Hill (USA) and North Carolina State University (USA).…”

“…[8][9][10] This year's honorees represent the best in research that advances translational science and technology, and we are proud to honor these researchers for their amazing work. JALA and SLAS would like to thank all the nominees as well as those who nominated them.…”

“…7 Beyond building better biosensors and more effective and cost-efficient devices, work featured this year includes improvements in automation of large-cargo intracellular delivery, as well as innovating the use of inorganic and biomaterials in medical applications. [8][9][10] This year's honorees represent the best in research that advances translational science and technology, and we are proud to honor these researchers for their amazing work. JALA and SLAS would like to thank all the nominees as well as those who nominated them.…”