Welcome to the new version of CaltechAUTHORS. Login is currently restricted to library staff. If you notice any issues, please email coda@library.caltech.edu
Published June 7, 2009 | Accepted Version
Journal Article Open

In vivo carbon nanotube-enhanced non-invasive photoacoustic mapping of the sentinel lymph node


Sentinel lymph node biopsy (SLNB), a less invasive alternative to axillary lymph node dissection (ALND), has become the standard of care for patients with clinically node-negative breast cancer. In SLNB, lymphatic mapping with radio-labeled sulfur colloid and/or blue dye helps identify the sentinel lymph node (SLN), which is most likely to contain metastatic breast cancer. Even though SLNB, using both methylene blue and radioactive tracers, has a high identification rate, it still relies on an invasive surgical procedure, with associated morbidity. In this study, we have demonstrated a non-invasive single-walled carbon nanotube (SWNT)-enhanced photoacoustic (PA) identification of SLN in a rat model. We have successfully imaged the SLN in vivo by PA imaging (793 nm laser source, 5 MHz ultrasonic detector) with high contrast-to-noise ratio (=89) and good resolution (~500 µm). The SWNTs also show a wideband optical absorption, generating PA signals over an excitation wavelength range of 740–820 nm. Thus, by varying the incident light wavelength to the near infrared region, where biological tissues (hemoglobin, tissue pigments, lipids and water) show low light absorption, the imaging depth is maximized. In the future, functionalization of the SWNTs with targeting groups should allow the molecular imaging of breast cancer.

Additional Information

© 2009 Institute of Physics and Engineering in Medicine. Received 21 January 2009; In final form 2 March 2009; Published 8 May 2009. This work was supported by National Institutes of Health grants (R01 EB000712, R01 NS46214 (Bioengineering Research Partnerships), R01 EB008085 and U54 CA136398 (Network for Translational Research)—LVW) and the Office of the Vice President of Research at Stony Brook University, Carol M. Baldwin fund (SB). LW has a financial interest in Endra, Inc., which, however, did not support this work. The authors would like to thank Dr Oleg Gang and Dr Huming Xiong at the Center for Functional Nanomaterials, Brookhaven National Laboratory, for access to the AFM, Mr Tom Salagaj and Mr Christopher Jensen at FirstNano/CVD Equipment Corporation for access to their CVD facilities and Dr Eunah Lee at Horiba JvonYvon, Edison, NJ, for the Raman Spectroscopy measurements.

Attached Files

Accepted Version - nihms119544.pdf


Files (1.8 MB)
Name Size Download all
1.8 MB Preview Download

Additional details

August 20, 2023
October 20, 2023