Back to top

Colloquium - Bubble Trouble: Conquering Microbubble Constraints in Ultrasound Molecular Imaging of Cancer by Using Echogenic Nanobubbles

Monday, March 12, 2018 - 13:30
KHE 225

Speaker: Dr. Agata A. Exner
Department of Radiology, Case Western Reserve University, Cleveland, Ohio USA


The ability to formulate robust contrast agents able that penetrate deep into tumors (to detect cell surface markers or molecules in the tissue) is critical to the development of ultrasound as a molecular imaging tool. Yet small size highly echogenic agents have been elusive. Conventional microbubble contrast agents currently used are intravascular contrast agents unable to penetrate into tumors due to their large size (typically 2-3 µm). We are developing unique lipid-surfactant and surfactant stabilized nanobubbles with a gas perfluorocarbon code which are visible at 6-18 MHz and beyond, yet sufficiently small (~200-300 nm) to move beyond the leaky tumor vasculature. Surface functionalization of nanobubbles permits greatly expanded molecular imaging capabilities of ultrasound. Here we will present recent data supporting the formulation of echogenic nanobubbles, evaluating their unique in vitro biophysical and acoustic behavior and showcasing their application in ultrasound molecular imaging of prostate cancer via targeting of the prostate specific membrane antigen (PSMA).


Dr. Exner is Professor of Radiology and Biomedical Engineering at Case Western Reserve University School of Medicine in Cleveland, Ohio. Her research focuses on the development of nanobubble contrast agents for ultrasound molecular imaging and ultrasound-enhanced drug delivery for cancer detection and therapy, and engineering drug-eluting polymer implants for intratumoral chemotherapy. Dr. Exner is a Fellow of the Academy of Medical and Biological Engineering, Distinguished Investigator of the Academy of Radiology Research, and Associate Editor of the Annals of Biomedical Engineering.