Issue 2, 2015

Microfluidic system for high throughput characterisation of echogenic particles


Echogenic particles, such as microbubbles and volatile liquid micro/nano droplets, have shown considerable potential in a variety of clinical diagnostic and therapeutic applications. The accurate prediction of their response to ultrasound excitation is however extremely challenging, and this has hindered the optimisation of techniques such as quantitative ultrasound imaging and targeted drug delivery. Existing characterisation techniques, such as ultra-high speed microscopy provide important insights, but suffer from a number of limitations; most significantly difficulty in obtaining large data sets suitable for statistical analysis and the need to physically constrain the particles, thereby altering their dynamics. Here a microfluidic system is presented that overcomes these challenges to enable the measurement of single echogenic particle response to ultrasound excitation. A co-axial flow focusing device is used to direct a continuous stream of unconstrained particles through the combined focal region of an ultrasound transducer and a laser. Both the optical and acoustic scatter from individual particles are then simultaneously recorded. Calibration of the device and example results for different types of echogenic particle are presented, demonstrating a high throughput of up to 20 particles per second and the ability to resolve changes in particle radius down to 0.1 μm with an uncertainty of less than 3%.

Graphical abstract: Microfluidic system for high throughput characterisation of echogenic particles

Supplementary files

Article information

Article type
13 Oct 2014
28 Oct 2014
First published
28 Oct 2014
This article is Open Access
Creative Commons BY license

Lab Chip, 2015,15, 417-428

Author version available

Microfluidic system for high throughput characterisation of echogenic particles

P. Rademeyer, D. Carugo, J. Y. Lee and E. Stride, Lab Chip, 2015, 15, 417 DOI: 10.1039/C4LC01206B

This article is licensed under a Creative Commons Attribution 3.0 Unported Licence. You can use material from this article in other publications without requesting further permissions from the RSC, provided that the correct acknowledgement is given.

Read more about how to correctly acknowledge RSC content.

Social activity