Academic journal article The Science Teacher

Good as Gold

Academic journal article The Science Teacher

Good as Gold

Article excerpt

Informat ion obtained f rom a new application of photoacoustic tomography (PAT) is worth its weight in gold to breast cancer patients. For the first time, two biomedical enginners have used gold nanocages to noninvasively map sentinel lymph nodes (SLN) in a rat using PAT. Lihong Wang is the Gene K. Beare distinguished professor in the Department of Biomedical Engineering, with a joint appointment in radiology, and Younan Xia is the James M. McKelvey professor in biomedical engineering, with a joint appointment in chemistry in Arts and Sciences, both at Washington University in St. Louis (WUSTL).

Their work, supported by the National Institutes of Health, can minimize invasive surgical lymph node biopsy procedures to determine if breast cancer has metastasized and reduce the patient's exposure to radioactivity. The nanocages also have the potential to serve as an alternative to chemotherapy, to kill targeted cancers by heating them up. The research was published in an online issue of Nanoletters.

PAT blends optical and ultrasonic imaging to give high-resolution images of the body that contain information about physiology or tissue function. Endogenous molecules (already present in the body), such as melanin, hemoglobin, or lipids, can be used as endogenous contrast agents for imaging. When light is shone on the tissue, the contrast agent absorbs the light, converts it to heat, and expands. This expansion is detected as sound and decoded into an image.

"Using pure optical imaging, it is hard to look deep into tissues at high resolution because light scatters. The useful photons run out of juice within 1 mm," Wang explains. "PAT improves tissue transparency by two to three orders of magnitude because sound scatters less than light. …

Search by... Author
Show... All Results Primary Sources Peer-reviewed

Oops!

An unknown error has occurred. Please click the button below to reload the page. If the problem persists, please try again in a little while.