Abstract

Bare (similar to 10 nm) and heparin (HP)-coated superparamagnetic iron oxide nanoparticles (SPIO NPs; 42 nm) were formulated by a co-precipitation technique. The bare and HP-SPIO NPs had saturation magnetization of 50-55 emu g(-1) at 300 K. The anticancer drugs, doxorubicin (DOX) and paclitaxel (PTX), were separately partitioned in the SPIO core to compare their anti-neoplastic effects on the proliferation of A2780 and OVCAR-3 human ovarian cancer cells. The results revealed that the DOX-HP-SPIO NPs (85 nm) and PTX-HP-SPIO NPs (71 nm) showed sustained and pH-sensitive release of DOX (87) and PTX (75), respectively, at pH 6.0, even up to two weeks. Meanwhile, 10 mu g ml(-1) DOX-HP-SPIO NPs and PTX-HP-SPIO NP caused 95 and 84, and 85 and 77 apoptosis in A2780 and OVCAR-3 cells, respectively, with a sharp decrease in the level of bcl-2 and survivin proteins and increased expression of proapoptotic proteins, like bax and NF-kappa B. So, the presently formulated nanocomposite-based drug delivery system was readily internalized into tumor cells and induced a higher apoptosis rate.