Seminar on Design of co-assembled amino acid-based nanoparticles for combined chemo- and phototherapy

Dr Alberto Bianco

CNRS, Immunology, Immunopathology and Therapeutic Chemistry, University of Strasbourg, France

The self-assembly of amino acids derivatives and their applications in the biomedical field have drawn much attention in the past years. In this seminar, the binary nanoparticles made of co-assembled Fmoc-protected aromatic amino acids are presented for drug delivery and combined cancer therapy. Fmoc-Tyr-OH and Fmoc-Phe-OH self-assemble into nanofibers, while the structure is transformed into nanoparticles when it is co-assembled using Fmoc-Trp-OH. The self-assembly is driven by non-covalent interactions, making the formed nanomaterials unstable and limiting their further development. For this reason, we introduced the covalent dityrosine bonds by crosslinking the side chains irradiating at 254 nm or at 365 nm in the presence of riboflavin as photo-initiator. When compared with the non-crosslinked nanoparticles, both mechanical strength and chemical stability of these nanoparticles were remarkably enhanced. These nanoparticles were then used for drug delivery, adsorbing the anticancer drug doxorubicin (Dox), and subsequently coating them by a tannic acid-iron complex, which endow them with glutathione-responsiveness and photothermal properties, for a controlled release of Dox. A remarkable anticancer efficiency was obtained in vitro and in vivo in tumour-bearing mice, thanks to the combined chemo- and photothermal treatment.