Gas-filled lipid microbubbles are emerging as a next generation ‘theranostic’ tool in the medical arena. Initially developed as a diagnostic aid to improve echogenicity in ultrasound imaging, their therapeutic potential has now been realized also, through their somewhat unique ability to deliver molecular species such as drugs and genes by disrupting the cell membrane, again in response to ultrasound wave stimulus. The distinct aim for the present study was to produce monodisperse microbubbles, which it is hoped will have a more easily controlled, and thus clinically reliable, response to pulsed ultrasound. In pursuit of this, we designed a glass microfluidic chip with a distinctive flow focussing junction where the liquid and gas phases meet and are collected into an outlet channel [1] (see figure below). The shell material was composed of lipid mixed with poly ethylene glycol 2000 (PEG2000) and the gas core was either nitrogen or perfluorobutane. The chip and associated apparatus were set up under an inverted microscope (Axiovert 200, Zeiss, Germany) in a clean room, and generation of microbubbles was readily observed. The diameter of the microbubbles formed was 2 – 10 µm, depending upon the liquid and gas flow parameters. At the high flow rates required [at 152 kPa gas pressure and 1.5 – 2 µl min−1 liquid flow rate] for reasonable throughput, specific nuances of the bubble formation process such as pinch-off and location within the flow arc of the microfluidic channels could be readily discerned, parameters that will inform next generation designs for our chip. The high-speed camera used for all of this work was a HPV-1 (Shimadzu, Japan).

© 2011 Optical Society of America

PDF Article
More Like This
Pulsed Laser Triggered High Speed Microfluidic Fluorescence Activated Cell Sorter

Ting-Hsiang Wu, Yue Chen, Sung-Yong Park, and Eric Pei-Yu Chiou
CMDD2 CLEO: Science and Innovations (CLEO_SI) 2011

Turbidity measurements on suspended lipid microbubble populations subjected to ultrasound

Timur Saliev, Loreto B. Feril, Katsuro Tachibana, and Paul A. Campbell
JTuA20 Bio-Optics: Design and Application (BODA) 2011

Generation of Photonic Shell Microbubbles

Elizabeth Huynh, Jonathan F. Lovell, Brandon Helfield, Chulhong Kim, David E. Goertz, and Gang Zheng
BSu3A.55 Biomedical Optics (BIOMED) 2012


You do not have subscription access to this journal. Citation lists with outbound citation links are available to subscribers only. You may subscribe either as an OSA member, or as an authorized user of your institution.

Contact your librarian or system administrator
Login to access OSA Member Subscription