Lipid Based Nanovectors Containing Ruthenium Complexes: A Potential Route in Cancer Therapy

Metastases rather than primary tumors are the leading cause for cancer death, and yet metastases are almost never the target of chemotherapy. At present, Ruthenium complexes have been found to offer new perspectives. Although a rather large number of studies on Ruthenium complexes have been published in the recent years, up to date in literature no examples of nanovectors carrying Ruhenium complexes for anticancer therapy are reported. At this aim, we have synthesized a new amphiphilic unimer able to coordinate Ruthenium complexes and to form liposomes. This unimer (DOPU) has been obtained from an uridine derivative by traightforward introduction of a pyridine function on the uracile base. The hydrophobic part of the molecule consists of a double C18 oleoyl chain. The ligand unimer DOPU has been afterward coordinated to Ru(III). Preliminary SANS, Cryo-TEM and DLS measurements have confirmed the presence of unilamellar and oligolamellar liposomes, as well as the existence of more complex structures like cubosomes. The findings in the present study open up new vistas for the application of lipid based supramolecular systems in Ruthenium anti-cancer therapy. The lodgment of Ruthenium complexes in amphiphilic nanovectors allows a higher amount of drug in the bloodstream compared to the case when it is administrated as a free complex. Furthermore, amphiphilic nanovectors are able to protect the Ruthenium complexes from enzymatic and/or environmental degradation that could otherwise occur during bloodstream circulation.