Gold nanoparticles and nanorods for copper complexes delivery

The vehicle and release of therapeutic materials to specific targets, still represent a challenge to which the biomedicine and biomaterials are called. A worthy response is represented by gold nanoparticles and nanorods (AuNPs and AuNRs) that are widely applied for biomedical uses such as imaging/diagnostic tools, drug and gene delivery.[1-3] Their success is due to their easy surface modification and exclusive chemical and physical properties. In this framework, we report a study about functionalized AuNPs and AuNRs used as vehicles for antitumoral compounds, based on copper complexes. These nanomaterials are optimized to increase the hydrophilia of the drug delivery systems and to improve the bioavailability of the water insoluble drugs. AuNPs and AuNRs were synthesized using hydrophilic thiols as capping agents with several Au/S molar ratios (1/1;1/2;1/4). The nanosystems were characterized by means of several spectroscopic techniques (Uv-visible, FTIR, XPS) and by DLS, confirming their nanodimension and the surface functionalizations. The AuNPs were tested as carrier for Cu(I) and Cu(II) complexes. [4,5] Depth studies were performed to improve the drug loading on AuNPs (loading efficiency 65-80%) and the stability of the conjugate systems. Moreover preliminary release studies show a slow release profile.