Electrocontrolled Liquid Marbles for Rapid Miniaturized Organic Reactions

Abstract

Miniaturized droplet reactors hold great promise for the development of green and sustainable chemistry. However, handling liquids with small volumes, especially viscous ones, in a convenient and loss-free manner remains a challenge. Here, by electrically controlling the coalescence and mixing of particle-coated droplets, also known as liquid marbles, an effective micro reactor is demonstrated for miniaturized chemical reactions involving viscous reagents. By applying an electric voltage to marbles, the induced electromixing of marble microreactors promotes the reaction rate and the product yield. The advantages of electromixed marble reactors are manifested by a series of chemical reactions between aldehydes and 2-methylindole in viscous glycerol solution. The electrically-controlled coalescence and mixing establish liquid marbles as microreactors for rapid, efficient, and miniaturized chemical reactions.

Liquid Marbles in Liquid

“…[ 16–19 ] Compared with the uncoated “naked” droplets, LMs can be manipulated as non‐sticky fluidic cells with significantly reduced surface friction and increased drop operability. [ 20–22 ] Based on the nature of the internal fluid and variations of physical properties of coated particles, external stimuli such as electric field, [ 23–26 ] photon, visible light, [ 27 ] magnetic field, [ 28,29 ] and mechanical force [ 30–32 ] can be used to manipulate the LMs’ properties. In addition, LMs with shells composed of multilayers of particles can be engineered for precise control of chemical dosing by allowing them to coalesce and disintegrate at specific interval.…”

Liquid Marbles: A Promising and Versatile Platform for Miniaturized Chemical Reactions

“…In a recently published paper by Liu et al., the first case of an electric‐field‐triggered coalescence and rapid miniaturized organic reaction in a viscous solvent was reported . The direct current (DC) voltage on two adjacent LMs was adjusted such that coalescence occurred when a critical value U c was reached (Figure ).…”

Influence of water evaporation/absorption on the stability of glycerol–water marbles

“…[23][24][25][26][27] Given the exibility in the choice of solid particles and liquids to fabricate liquid marbles, liquid marbles are emerging as a versatile platform for a wide range of applications in miniature reactors, microuidics, drug transport, gas sensing, and biomedical and genetic analyses. [2][3][4][5][6] As a versatile and cost-effective miniature reactor providing a well-conned microenvironment, [28][29][30][31][32] progress in miniaturized chemical and biological processes using liquid marbles has been reported recently. The miniaturized synthesis of graphene/ Ag nanocomposites was demonstrated using liquid marbles.…”