Molecular beacon signals low oxygen with ultrasound

CHAMPAIGN, Ill. — Areas of hypoxia, or low oxygen in tissue, are hallmarks of fast-growing cancers and of blockages or narrowing in blood vessels, such as stroke or peripheral artery disease. University of Illinois researchers have developed a way to find hypoxic spots noninvasively in real time. The researchers developed an oxygen-sensitive molecular beacon that emits ultrasound signals in response to light, a process called photoacoustic imaging - a less invasive, higher resolution and less costly method than the current clinical standard, which uses radioactive molecules and positron emission tomography scans. In a paper published , the researchers demonstrated the probe's ability to image hypoxic tumors and constricted arteries in mice. "We could give a doctor a three-dimensional, real-time view into the tissue to guide surgical procedures and treatment plans," said chemistry professor Jefferson Chan , the leader of the study. Graduate student Hailey Knox and bioengineering professor Wawrzyniec Lawrence Dobrucki were co-authors of the paper.