Polylysine-grafted Au144 nanoclusters: birth and growth of a healthy surface-plasmon-resonance-like band.
نویسندگان
چکیده
Poly(amino acid)-coated gold nanoparticles hold promise in biomedical applications, particularly because they combine the unique physicochemical properties of the gold core, excellent biocompatibility, and easy functionalization of the poly(amino acid)-capping shell. Here we report a novel method for the preparation of robust hybrid core-shell nanosystems consisting of a Au144 cluster and a densely grafted polylysine layer. Linear polylysine chains were grown by direct N-carboxyanhydride (NCA) polymerization onto ligands capping the gold nanocluster. The density of the polylysine chains and the thickness of the polymer layer strongly depend on the amount and concentration of the NCA monomer and the initiator. The optical spectra of the so-obtained core-shell nanosystems show a strong surface plasmon resonance (SPR)-like band at 531 nm. In fact, despite maintenance of the gold cluster size and the absence of interparticle aggregation, the polylysine-capped clusters behave as if they have a diameter nearly 4 times larger. To the best of our knowledge, this is the first observation of the growth of a fully developed, very stable SPR-like band for a gold nanocluster of such dimensions. The robust polylysine protective shell makes the nanoparticles very stable under conditions of chemical etching, in the presence of glutathione, and at different pH values, without gold core deshielding or alteration of the SPR-like band. This polymerization method can conceivably be extended to prepare core-shell nanosystems based on other mono- or co-poly(amino acids).
منابع مشابه
Polylysine-grafted Au144 nanoclusters: birth and growth of a healthy surface-plasmon-resonance-like band† †Electronic supplementary information (ESI) available: Full experimental details on methods and syntheses, and further characterization results. See DOI: 10.1039/c6sc05187a Click here for additional data file.
Institute of Chemistry, St. Petersburg State Petrodvorets, St. Petersburg, Russia. E-mail: Department of Chemistry, University of Pad E-mail: [email protected] Department of Physics, St. Petersburg Sta Petrodvorets, St. Petersburg, Russia Department of Biomedical Engineering, U Road, Storrs, Connecticut 06269, USA Polymer Program, Institute of Materials S Eagleville Rd, Storrs, Connecticut 0...
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ورودعنوان ژورنال:
- Chemical science
دوره 8 4 شماره
صفحات -
تاریخ انتشار 2017