Inorganic gold nanoparticles-TAT hybrid for the effective delivery of doxorubicin into cancer cells

Recent years have witnessed an upsurge in the demand of new methodologies for effective anti-cancer drug delivery using green routes. In this direction, in the present work, synthesis of highly stable gold nanoparticles using aspartic acid as capping agent (GNPs) has been reported. This system was used for the efficient delivery of potent anti-cancer drug doxorubicin (Dox). To increase the cellular internalization, GNPs were loaded with cationic cell penetrating peptide, TAT via covalent or non-covalent interactions (GNPs-TAT). A high loading of TAT peptide (81.6% ± 1.84%) on GNPs was achieved successfully and was approximately double as compared to the conventional approaches (42.3% ± 1.58%). GNPs-TAT showed enhanced cellular uptake into HeLa cells in comparison to the bare GNPs which confirmed the penetrating effect of TAT peptide. Further, Dox was conjugated with GNPs-TAT via electrostatic interactions. The developed chemotherapeutic system (GNPs-TAT-Dox) showed enhanced Dox release (>80%) at acidic pH as compared to physiological pH. The cell viability results against HeLa cells indicated that the cytotoxic efficiency of the chemotherapeutic system increased twice as compared to the free Dox. Therefore, the results established a promising application of gold nanoparticles for improved drug delivery in cancer.