POLY 236 |
| Echogenic polymeric nanoparticles that combine properties of drug carriers and ultrasound contrast agents were developed. At room temperature, drug-loaded formulations comprise a mixture of polymeric micelles and nanoemulsions. Upon heating to physiological temperature, nanodroplets convert into highly echogenic microbubbles. The phase state of the system, and the size and stability of nanoparticles depend on the type of particle stabilizing copolymer and copolymer concentration. The microbubbles significantly enhance ultrasound-triggered intracellular drug uptake by tumor cells.Experiments were performed in vitro and in vivo using drug-sensitive and multidrug resistant breast cancer tumor models in nu/nu mice. A significant increase in the local drug uptake, decrease of tumor growth rate, prolonged progression-free time, and enhanced animal survival rates were observed. The nanoemulsions and microbubbles manifested high ultrasound contrast in phantom capillaries. |
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7th International Biorelated Polymers Symposium
8:30 AM-12:40 PM, Monday, 11 September 2006 San Francisco Marriott -- Salon 14/15, Oral
Division of Polymer Chemistry |