Peptide-Functionalized Gold Nanorods as a Model to Reach the Cell Nucleus: Synthesis and Structural Characterizations in View of Theragnostic Applications

Gold nanoparticles are proving to be highly successful for delivering drugs to specific targets, exploiting carefully designed functionalizations. This work creates and optimizes the synthesis of gold nanorods (AuNRs), subsequently functionalized with a peptide, TAT, appropriately modified to allow attachment to the rods and guide their entry into the cell nucleus and nuclear growth. Various chemical and physical characterizations were performed to verify and optimize the AuNRs-TAT system. DLS, Z-potential, UV-vis, and FT-IR spectroscopies confirmed the nanosize, monodispersity, colloidal stability, and successful functionalization. Furthermore, structural characterizations conducted using synchrotron radiation were crucial for understanding the actual interaction between the gold surface and the modified TAT peptide. The study highlighted how this material is indeed a good drug delivery system, stable over time, and promising for reaching the cell nucleus.