Superheated nanodroplets for contrast-enhanced tumour imaging

Michel Versluis and Nico de Jong of Detlef Lohse's Physics of Fluids research group at the University of Twente were granted €350,000 in the FOM Projectruimte. The grant is intended for research into a new contrast agent for tumour imaging using ultrasound.

The grant has been awarded in the FOM Projectruimte, which issues grants to applicants who conduct innovative, cutting-edge fundamental research in the field of physics. The proposed research must be of high quality and address urgent scientific, industrial or societal needs.

Nanodroplets
The new contrast agent consists of encapsulated nanodroplets with a boiling point slightly below body temperature. Once injected in the bloodstream, the droplets become superheated. The droplets are so tiny that they can flow through the leaky vasculature of a tumour where they accumulate. An impulsive focused ultrasound pulse causes explosive vaporization of the droplets and the pulse-echo scattering of the resulting vapour bubbles can be efficiently picked up using an ultrasound scanner.

The main focus of the research project is to gain a fundamental understanding of the vaporization process for controlled and improved diagnostic imaging. Therapeutic applications through targeted drug delivery with similar nanodroplets should be feasible in the near future. "Current tumour chemotherapy is associated with severe side effects caused by adverse effects of the drugs on healthy tissue. A local delivery of the drug has the advantage of a more controlled biodistribution of the therapeutic agent, which will reduce the side-effects and offers the potential to use a higher concentration which will improve therapeutic efficiency" Michel Versluis explains.

High-speed camera
The research will take place in close collaboration with Philips Research and Erasmus MC in Rotterdam. Michel Versluis continues "Very promising results have already been achieved in the US and Canada using these nanodroplets, in terms of both imaging and treatment of tumours. The details of how and why this works, the physical understanding of the vapour bubble dynamics, remain unexplored owing partly to the nanoseconds timescales of the phase conversion process. In our group we will focus specifically on studying the vaporization mechanism with the Brandaris camera, the fastest camera in the world. It is capable of shooting 25 million images per second. Using ultra-high-speed fluorescence techniques, we will also visualize the resulting drug release in the target area."

The new research is closely related to ongoing spearhead research in the MESA+ Institute for Nanotechnology and the MIRA Institute for Biomedical Technology and Technical Medicine at the University of Twente.

Provided by University of Twente