Microbubble formulation for ultrasound imaging
Data di pubblicazione
Data di priorità
Politecnico di Milano, VTT, CNRS
Department of Chemistry Materials and Chemical Engineering
Pierangelo Metrangolo, Giuseppe Resnati, Roberto Milani (VTT), Marie-Pierre Krafft (CNRS)
This invention is focused on the preparation of small and narrowly dispersed microbubbles that are both stable and echogenic by using compounds that are biologically inert.
The stabilization of aqueous microbubbles can be achieved in two ways:
- decreasing the water solubility of the gas contained in the bubble by incorporating tiny amount of a fluorocarbon gas (perfluorohexane) and
- assembling a protective layer around the bubble (hydrophobin HFBII), which decreases the surface tension and provides a physical barrier towards gas dissolution in water and bubble coalescence.
The perfluorohexane acts as a co-surfactant by being inserted in between the HFBII molecules, thereby reducing their lateral interactions. In addition, perfluorohexane acts at the interface, resulting in an acceleration of the adoption of HFBII at the gas/water interface and a significant reduction of HFBII surface tension at the equilibrium, this facilitating formation of micrometric bubbles.
The dispersions are prepared by treating and aqueous HFBII solution with a homogenizer for short duration (about two minutes) under an atmosphere of air saturated with perfluorohexane.
Campo di applicazione
The microbubbles are suitable as contrast agents in ultrasound imaging, for diagnostic, therapeutic and theranostics applications and in food technology.
The microbubbles are stable, highly echogenic and have a regular spherical shape.
They show a shelf-life of months and a half-life of a few hours under ultrasound irradiation.
All the compounds are biologically inert.