Near Infrared Circularly Polarized Luminescence From Water Stable Organic Nanoparticles Containing a Chiral Yb(III) Complex
Enrico Cavalli, Chiara Nardon, Oliver G. Willis, Francesco Zinna, Lorenzo Di Bari, Silvia Mizzoni, Silvia Ruggieri, Salvatore Calogero Gaglio, Massimiliano Perduca, Claudio Zaccone, Alessandro Romeo, Fabio Piccinelli
Abstract
Abstract We report the first example of very efficient NIR Circularly Polarized Luminescence (CPL) (around 970 nm) in water, obtained thanks to the combined use of a chiral Yb complex and of poly lactic‐co‐glycolic acid (PLGA) nanoparticles. [Yb L (tta) 2 ]CH 3 COO ( L =N, N’‐bis(2‐pyridylmethylidene)‐1,2‐( R,R + S,S ) cyclohexanediamine and tta=2‐thenoyltrifluoroacetonate) shows good CPL in organic solvents, because the tta ligands efficiently sensitize Yb NIR luminescence and the readily prepared chiral ligand L endows the complex with the necessary dissymmetry. PLGA nanoparticles incorporate the complex and protect the metal ion from the intrusion of solvent molecules, while ensuring biocompatibility, water solubility and stability to the complex. Hydrophilic NIR‐CPL optical probes can find applications in the field of NIR‐CPL bio‐assays.