Superparamagnetic nanovector with anti-cancer properties: γFe2O3@Zoledronate

We elaborate a magnetic nanovector to vectorize Zoledronate, an anti-cancer interest molecule of the hydroxmethylenebisphosphonate's family. In fact, Zoledronate is a powerful adjuvant in the treatment of bone diseases such as osteoporosis and Paget's disease. But, recent studies have shown that in addition to anti-osteoclastic properties, it presents antitumour properties notably in the case of breast and prostate cancer. However, these properties cannot be exploited due to their very high affinity to divalent cations and their preferentially accumulation in bone. To overcome this problem, one strategy is the vectorization trough maghemite nanocrystal functionalization. The specific surface coating permits to consider gamma Fe2O3@Zoledronate as a drug delivery vehicle for therapeutic activity. The anchoring to the nanoparticle's surface allowed to increase their hydrophobicity and also to change the therapeutic target, increasing the Zoledronate intestinal absorption instead of their accumulation in bone. We show that Zoledronate link the nanoparticle surface through phosphonate groups. The biological in vitro tests performed on breast cancer cell line, MDA-MB 231, showed that gamma Fe2O3@Zoledronate have anti proliferative activity. In addition, the gamma Fe2O3 core could be used as MRI contrast agent for a good therapeutic evaluation. (C) 2009 Elsevier B.V. All rights reserved.