Highly Flexible and Ultraprecise Manipulation of Light-Levitated Femtoliter/Picoliter Droplets

Abstract

Ultraprecise manipulation of the droplets at the microscale is a promising paradigm for broad implications in reagent transport and element analysis, but the existing strategies still suffer from cross-contamination or the miscellaneous auxiliaries. Inspired by the levitation, we develop a method for excellently manipulating levitated femtoliter/picoliter droplets by a single focused laser. We show that the unique lightinduced vapor flow in association with the interface morphology is responsible for creation and manipulation of levitated droplets. In particular, we demonstrate that the levitated droplets formed by this light method show extraordinary motility. The highly accurate two-dimensional labyrinth movement of the levitated droplets with designed trajectories above the free surface is easily realized by scanning the light. These results demonstrate that a single focused light can function as an "optical baton" to enable us to construct a wide variety of the long-sought precise manipulation systems for bioassays, pharmacy, and chemosynthesis.

Light-Fueled Beating Coffee-Ring Deposition for Droplet Evaporative Crystallization

“…This is because the droplet on the hydrophilic surface has a small contact angle and curvature. The ingenious vapor flow field associated with a small-curvature interface and the focused light-induced evaporation are together responsible for generating these levitated droplets . This is why there was no levitated droplets for the case of the droplet evaporative crystallization on the hydrophobic surface.…”

“…The ingenious vapor flow field associated with a small-curvature interface and the focused light-induced evaporation are together responsible for generating these levitated droplets. 30 This is why there was no levitated droplets for the case of the droplet evaporative crystallization on the hydrophobic surface. However, the existence of the levitated droplets would not affect the droplet evaporative crystallization.…”

“…Recently, a new method to actuate Marangoni flow via the light-caused mechanism has been proposed, which brings the possibility of addressing the abovementioned issues with high spatiotemporal resolution and rapid response due to the light nature. − The photothermal effect is one of the light-caused physical mechanisms that can rapidly convert light energy into heat to actuate thermal instability and then induce the internal flow. − Conspicuously, due to high reconfigurability, the light beam can be easily split into multiple light beams by a beam splitter, , which can potentially allow for the realization of the parallel manipulation of multiple droplets. Hence, using the photothermal effect to induce Marangoni flow in droplets for the condensed deposition is able to show promise in relevant applications.…”

Microfluidics for Biosynthesizing: from Droplets and Vesicles to Artificial Cells

“…Light‐controlled manipulation of droplets possess the advantages of controllability, highly spatial precision, and noncontact actuation . As shown in Figure E, Abate and his colleagues reported a printed droplet microfluidics for the on demand and high‐throughput manipulation of picoliter droplets and cells .…”

Динамика Капель, Подброшенных Над Испаряющейся Поверхностью Воды

“…Наметились приложения в области вирусологии [12]. В мире получили распространение несколько аналогов используемой лабораторной установки [1,13,14]. Недавно вышедший обзор о левитации капель показал, что технология капельного кластера далеко не исчерпала своих возможностей и остается актуальной [15].…”