Combined optical sizing and acoustical characterization of single freely-floating microbubbles

In this study we present a combined optical sizing and acoustical characterization technique for the study of thedynamics of single freely-floatingultrasound contrast agent microbubbles exposed to long burstultrasound excitations up to the milliseconds range. A co-axial flow device was used to position individual microbubbles on a streamline within the confocal region of threeultrasound transducers and a high-resolution microscope objective. Bright-fieldimages of microbubbles passing through the confocal region were captured using a high-speedcamera synchronized to the acoustical data acquisition to assess the microbubble response to a 1-MHzultrasound burst.Nonlinear bubble vibrations were identified at a drivingpressure as low as 50  kPa. The results demonstrate good agreement with numerical simulations based on the shell-buckling model proposed by Marmottantet al. [J. Acoust. Soc. Am.118, 3499 –3505 (2005)]. The system demonstrates the potential for a high-throughputin vitro characterization of individual microbubbles.

Source: Applied Physics Letters - December 7, 2016 Category: Physics Authors: Ying Luan, Guillaume Renaud, Jason L. Raymond, Tim Segers, Guillaume Lajoinie, Robert Beurskens, Frits Mastik, Tom J. A. Kokhuis, Antonius F. W. van der Steen, Michel Versluis and Nico de Jong Source Type: research