A Simple and Cost-Effective Method for Producing Stable Surfactant-Coated EGaIn Liquid Metal Nanodroplets.

Bingbing Xu,Ruoxin Li,Guangtao Chang,Feng Ye

doi:10.3390/ma13173753

Abstract

Liquid metals show unparalleled advantages in printable circuits, flexible wear, drug carriers, and electromagnetic shielding. However, the efficient and large-scale preparation of liquid metal nanodroplets (LM NDs) remains a significant challenge. Here, we propose a simple and efficient method for the large-scale preparation of stable eutectic gallium indium nanodroplets (EGaIn NDs). We compared different preparation methods and found that droplets with smaller particle sizes could quickly be produced using a shaking technique. The size of EGaIn NDs produced using this technique can reach 200 nm in 30 min and 100 nm in 240 min. Benefiting from the simple method, various surfactants can directly modify the surface of the EGaIn NDs to stabilize the prepared droplets. In addition, we discovered that shaking in an ice bath produced spherical nanodroplets, and after shaking for 30 min in a non-ice bath, rod-shaped gallium oxide hydroxide (GaOOH) appeared. Furthermore, the EGaIn NDs we produced have excellent stability—after storage at room temperature for 30 days, the particle size and morphology change little. The excellent stability of the produced EGaIn NDs provides a wider application of liquid metals in the fields of drug delivery, electromagnetic shielding, conductive inks, printed circuits, etc.

Highlights

Liquid metals, as the name implies, are metals that are liquid below 300 ◦ C [1]
Preparation of eutectic gallium indium (EGaIn) NDs: First, 1 g of EGaIn, 1 g of synthetic dispersant (SP), and a small amount of defoamer were added into a bottle that was filled with deionized water to a total weight of 50 g and 300 g of zirconium beads (0.3–0.4 mm)
Of EGaIn, 1 g of SP, and a small amount of defoamer were added into a bottle that was filled with deionized water to a total weight of 50 g and 300 g of zirconium beads (0.3–0.4 mm)

Summary

Introduction

As the name implies, are metals that are liquid below 300 ◦ C [1]. Gallium-based liquid metals have unparalleled advantages in bioengineering, drug delivery, and tumor treatment because of their low toxicity and surface modification [4,5,6,7,8]. Gu et al utilized eutectic gallium indium (EGaIn) and thiolated polymers to form core–shell nanospheres, which were loaded with doxorubicin or hyaluronic acid for drug delivery and tumor treatment [9]. Miyako et al showed that photopolymerized liquid metal nanocapsules will generate heat and active oxygen under near-infrared irradiation, and cause the transformation of liquid metal (LM), leading to the destruction of the nanocapsule, thereby controlling release of the loaded drugs [10]. Liu et al proposed liquid metal angiography for the first time

Methods

Results

Conclusion