Apr 28, 2010
Nanobubble contrast agent reveals tumour imaging potential in ultrasound test
The Nanobiotechnology Group from Harbin Institute of Technology in collaboration with researchers at Peking University Third Hospital has successfully developed a novel biocompatible nanobubble ultrasound contrast agent that may provide a versatile adjunct for the enhancement of ultrasonic imaging and/or treatment of tumours.
To fabricate the nanobubble-based contrast agent, the researchers first ultrasonicate a mixture of Span 60 and polyoxyethylene 40 stearate and then use differential centrifugation to isolate the relevant subpopulation from the parent suspensions.
Excellent power Doppler enhancement was found in vivo in renal imaging following intravenous injection of the team's nanobubble contrast agent. The tiny bubbles are small enough to leak through the vascular pores of the tumour and accumulate in the tumour tissue by means of passive targeting due to the higher permeability of tumour blood vessels compared with normal tissue vasculature. After extravasations, an increased acoustic signal is obtained from the accumulated nanobubbles, providing strong ultrasound contrast imaging.
In addition to diagnostic applications, the nanobubbles show great potential as ultrasound-mediated drug-delivery vehicles to facilitate drug release and extravascular delivery.
More details can be found in the journal Nanotechnology.
About the author
This research is funded by NSFC, 863 program, and Cultivation Fund of the Key Scientific and Technical Innovation Project, Ministry of Education of China. Zhanwen Xing and Hengte Ke are currently pursuing their PhD degrees in the Nanobiotechnology Group at Harbin Institute of Technology under the supervision of Prof. Zhifei Dai. They focus on the design and fabrication of nano- and microbubbles that are capable of delivering active drugs and nanoparticles to target specific sites. Prof. Jinrui Wang and Prof. Jibin Liu are involved in the evaluation of contrast ultrasound imaging.