The Need for Monodisperse Microbubbles for Targeted Drug Delivery
The size heterogeneity and instability of conventional diagnostic imaging microbubbles has been a major problem in clinical translation of ultrasound contrast agents (UCAs) for targeted drug delivery applications. These microbubbles tend to be inherently polydisperse (broad) with discrepant number and volume weighted size distributions (see graphs below) and unstable in circulation - lasting only~5 to 10 mins. This leads to inconsistent acoustic or therapeutic response because microbubble resonance, scattering and attenuation under ultrasound is strongly dependent on size. For example, changing the diameter of a non-shelled microbubble from 1 to 5 μm will change the resonance frequency from 5 to 0.7 MHz.
We are the only company that develops ultrasound-triggered microbubbles optimized to solve the problems in drug delivery to treat various cancers. Our microbubbles are both uniform in size and stable in circulation for up 30 mins.