Abstract
Microbubbles interact with ultrasound in various ways to enable their applications
in ultrasound imaging and diagnosis. To generate high contrast and maximize therapeutic
efficacy, microbubbles of high uniformity are required. Microfluidic technology, which
enables precise control of small volumes of fluid at the sub-millimeter scale, has
provided a versatile platform on which to produce highly uniform microbubbles for
potential applications in ultrasound imaging and diagnosis. Here, we describe fundamental
microfluidic principles and the most common types of microfluidic devices used to
produce sub-10 μm microbubbles, appropriate for biomedical ultrasound. Bubbles can
be engineered for specific applications by tailoring the bubble size, inner gas and
shell composition and by functionalizing for additional imaging modalities, therapeutics
or targeting ligands. To translate the laboratory-scale discoveries to widespread
clinical use of these microfluidic-based microbubbles, increased bubble production
is needed. We present various strategies recently developed to improve scale-up. We
conclude this review by describing some outstanding problems in the field and presenting
areas for future use of microfluidics in ultrasound.
Key Words
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Article info
Publication history
Published online: September 19, 2018
Accepted:
July 27,
2018
Received in revised form:
July 5,
2018
Received:
April 27,
2018
Identification
Copyright
© 2018 Published by Elsevier Inc. on behalf of World Federation for Ultrasound in Medicine & Biology.
