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

• Published in: Applied physics letters 2016-12, Vol.109 (23)
• Main Authors: Luan, Ying, Renaud, Guillaume, Raymond, Jason L., Segers, Tim, Lajoinie, Guillaume, Beurskens, Robert, Mastik, Frits, Kokhuis, Tom J. A., van der Steen, Antonius F. W., Versluis, Michel, de Jong, Nico
• Format: Article
• Language: English
• Subjects: Applied physics; Axial flow; Computer simulation; Contrast agents; High speed cameras; Image resolution; Mathematical models; Sizing; Transducers; Ultrasonic imaging
• ISSN: 0003-6951; 1077-3118
• DOI: 10.1063/1.4971391

In this study we present a combined optical sizing and acoustical characterization technique for the study of the dynamics of single freely-floating ultrasound contrast agent microbubbles exposed to long burst ultrasound 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 three ultrasound transducers and a high-resolution microscope objective. Bright-field images of microbubbles passing through the confocal region were captured using a high-speed camera synchronized to the acoustical data acquisition to assess the microbubble response to a 1-MHz ultrasound burst. Nonlinear bubble vibrations were identified at a driving pressure as low as 50 kPa. The results demonstrate good agreement with numerical simulations based on the shell-buckling model proposed by Marmottant et al. [J. Acoust. Soc. Am. 118, 3499–3505 (2005)]. The system demonstrates the potential for a high-throughput in vitro characterization of individual microbubbles.