Jump to main content
Jump to site search

Issue 2, 2020
Previous Article Next Article

On-demand sample injection: combining acoustic actuation with a tear-drop shaped nozzle to generate droplets with precise spatial and temporal control

Author affiliations

Abstract

An on-demand droplet injection method for controlled delivery of nanolitre-volume liquid samples to scientific instruments for subsequent analysis is presented. We employ pulsed focussed surface acoustic waves (SAW) to eject droplets from an enclosed microfluidic channel into an open environment. The 3D position of individual droplets and their time of arrival can be precisely controlled to within 61 μs in a 500 μm square target region 40 μm wide. The continuous ejection rate of 16 000 droplets per second can be tuned to produce pulsed trains of droplets from 0 up to 357 Hz. The main benefit of this technique is its ease of integration with complex microfluidic processing steps, such as droplet merging, sorting, and encapsulation, prior to sample delivery. With its ability to precisely deliver a small quantity of fluid to a pre-defined location this technology is applicable in X-ray based molecular studies, including the rapidly expanding field of X-ray free electron lasers. Fabrication procedures for this device, the underlying forcing mechanism, the role of nozzle design, and demonstration of the performance in both continuous and on-demand modes are reported.

Graphical abstract: On-demand sample injection: combining acoustic actuation with a tear-drop shaped nozzle to generate droplets with precise spatial and temporal control

Back to tab navigation

Supplementary files

Article information


Submitted
22 Aug 2019
Accepted
13 Dec 2019
First published
13 Dec 2019

Lab Chip, 2020,20, 253-265
Article type
Paper

On-demand sample injection: combining acoustic actuation with a tear-drop shaped nozzle to generate droplets with precise spatial and temporal control

J. C. Brenker, C. Devendran, A. Neild and T. Alan, Lab Chip, 2020, 20, 253
DOI: 10.1039/C9LC00837C

Social activity

Search articles by author

Spotlight

Advertisements