Chiral supramolecular gold-cysteine nanoparticles: Chiroptical and nonlinear optical properties

• Main Authors: Isabelle Russier-Antoine, Franck Bertorelle, Alexander Kulesza, Antonin Soleilhac, Amina Bensalah-Ledoux, Stephan Guy, Philippe Dugourd, Pierre-François Brevet, Rodolphe Antoine
• Format: Article
• Language: English
• Published: Elsevier 2016-10-01
• Series: Progress in Natural Science: Materials International
• Subjects: Gold; Cysteine; Supramolecular chemistry; Nanoparticles; Chirality; Nonlinear optics
• Online Access: http://www.sciencedirect.com/science/article/pii/S1002007116300831

Cysteine is a sulfur-containing amino acid that easily coordinates to soft metal ions and grafts to noble metal surfaces. We report a simple synthetic approach for the production of chiral gold-cysteine polymeric nanoparticles soluble in water. Conjugation of cysteine with gold in a polymeric way, leading to ~50 nm diameter nanoparticles, resulted in the generation of new characteristic circular dichroism (CD) signals in the region of 250–400 nm, whereas no CD signal changes were found with cysteine alone. We also investigate their nonlinear optical properties after two-photon absorption. Two-photon emission spectra and first hyper-polarizabilities, as obtained by the hyper-Rayleigh scattering technique, of these particles are presented.