Research Papers

Ultrasound-modulated fluorescence based on a fluorophore-quencher-labeled microbubble system

[+] Author Affiliations
Baohong Yuan

Catholic University of America, Department of Biomedical Engineering, Pangborn Hall, 620 Michigan Avenue, NE, Washington, DC 20064

J. Biomed. Opt. 14(2), 024043 (April 17, 2009). doi:10.1117/1.3120493
History: Received August 20, 2008; Revised February 02, 2009; Accepted February 24, 2009; Published April 17, 2009
Text Size: A A A

Ultrasound-modulated fluorescence from a fluorophore-quencher-labeled microbubble system driven by a single ultrasound pulse was theoretically quantified by solving a modified Herring equation (for bubble oscillation), a two-energy-level rate equation (for fluorophore excitation), and a diffusion equation (for light propagation in tissue). The efficiency of quenching caused by fluorescence resonance energy transfer (FRET) between the fluorophore and the quencher was modulated when the microbubble oscillates in size driven by the ultrasound pulse. Both intensity- and lifetime-based imaging methods are discussed in three different illumination modes of the excitation light: continuous wave (DC), frequency domain (FD), and time domain (TD). Results show that microbubble expansion opens a time period during which the quenching efficiency is dramatically reduced so that the emitted fluorescence strength and fluorophore lifetime are significantly increased. The modulation efficiency may even reach 100%. In addition, an important finding in this study is that in TD illumination mode, the modulated fluorescence photons may be temporally separated from the unmodulated photons, which makes the modulation efficiency limited only by thermal noise of the measurement system.

Figures in this Article
© 2009 Society of Photo-Optical Instrumentation Engineers

Citation

Baohong Yuan
"Ultrasound-modulated fluorescence based on a fluorophore-quencher-labeled microbubble system", J. Biomed. Opt. 14(2), 024043 (April 17, 2009). ; http://dx.doi.org/10.1117/1.3120493


Access This Article
Sign in or Create a personal account to Buy this article ($20 for members, $25 for non-members).

Some tools below are only available to our subscribers or users with an online account.

Related Content

Customize your page view by dragging & repositioning the boxes below.

Related Book Chapters

Topic Collections

PubMed Articles
Advertisement


 

  • Don't have an account?
  • Subscribe to the SPIE Digital Library
  • Create a FREE account to sign up for Digital Library content alerts and gain access to institutional subscriptions remotely.
Access This Article
Sign in or Create a personal account to Buy this article ($20 for members, $25 for non-members).
Access This Proceeding
Sign in or Create a personal account to Buy this article ($15 for members, $18 for non-members).
Access This Chapter

Access to SPIE eBooks is limited to subscribing institutions and is not available as part of a personal subscription. Print or electronic versions of individual SPIE books may be purchased via SPIE.org.