Fig. 8.

Results of chemotherapy of a mouse with two ovarian carcinoma tumors; the mouse was treated by systemic injections of paclitaxel encapsulated into nanodroplets (nbGEN); the paclitaxel dose was 20 mg/kg; the right tumor was sonicated by the 1 MHz ultrasound at a nominal power density of 3.4 W/cm² in the persistent sonication mode; the exposure duration was 1 min. In order to prevent superheating of skin, a water-filled bag lubricated with an Aquasonic gel on either side was placed between the source and the mouse skin for ensuring acoustic contact; ultrasound was applied in 4.5 h after the drug injection. On the left, there is a photograph of the mouse before the treatment; the photograph on the right was taken in three weeks after the beginning of the treatment. The left (nonsonicated) tumor grew with the rate of the control tumors, whereas the right tumor (sonicated) regressed effectively. These results demonstrate that in the absence of ultrasound, paclitaxel is strongly retained by nanodroplets in vivo; however, it is effectively released under the action of ultrasound.