Farzaaneh zaery - Department of Pharmaceutics ,Faculty of Pharmacy ,Tehran University of Medical Sciences ,Tehran ,Iran .
Roghayeh Rastegar - Department of Biomaterials ,Faculty of Pharmacy ,Tehran University of Medical Sciences ,Tehran, Iran.
Mehdi Khoobi - Department of Medicinal Chemistry ,Faculty of Pharmacy ,Tehran University of Medical Sciences ,Tehran ,Iran
Hamid Akbari javar - Department of Pharmaceutics ,Faculty of Pharmacy ,Tehran University of Medical Sciences ,Tehran ,Iran .

Introduction: Breast cancer is the most common form of cancer (other than skin cancer) in women. 200,000 new cases of breast cancer detected each year of which40,000 will die. Nanotechnology has provided an alternative strategy of drug delivery to prevent drug efflux by offering encapsulation or attachment of drugs tonanomaterials such as lipids, polymers and solid-core nanoparticles. Methods: Iron oxide nanoparticles were prepared by using a conventional coprecipitation method and coated with silica using a sol−gel method to afford core-shell magnetic nanoparticles. Folic acid as a targeting agent was activated and attached to Polyethyleneimine. The polymer obtained was coated on magnetic cores. The core-shell nanoparticles were characterized by different methods. Doxorubicin was loaded into the nanoparticles andthe realese behavior was studied in different pH conditions. Results: Doxorubicin loading 54.6% was obtained and released drug in acidic pH was obviously more than physiologic pH. Conclusion According to the results we can optimize our core-shell nanostructure as an efficient drug delivery carrier as well as MRI contrast agent for breast cancer.

Magnetic nanoparticles, polyethyleneimine, Doxorubicin , breast cancer, drug delivery