A versatile Near Infrared Asymmetric Tricarbocyanine for Zinc Ion Sensing in Water

GUILLERMO MENENDEZ; CECILIA SAMANIEGO LOPEZ; ELIZABETH JARES-ERIJMAN; CARLA C. SPAGNUOLO

PHOTOCHEMISTRY AND PHOTOBIOLOGY

WILEY-BLACKWELL PUBLISHING, INC

Lugar: Londres; Año: 2013 vol. 89 p. 1354 - 1361

0031-8655

We have synthesized a near infrared emissive asymmetric tricarbocyanine conveniently functionalized to improve bioconjugation. The leading structure contains a versatile derivatization point at the meso position for facile radical-nucleophilic aromatic substitution. We have evaluated a DPEN (N,N-di(2-picolyl)ethylendiamine) derivative of this dye as a highly selective sensor for zinc (II) in aqueous medium, which performs in an appropriate sensitivity range for biological studies. The probe was successfully conjugated to a protein-ligand model with high affinity and specificity (biotin-streptavidin technology) rendering an excellent performance of sensing. In a general strategy to obtain sensitive probes combining fluorescent nanoparticles and molecular fluorophores, a preliminary design of a supramolecular assembly derived from the conjugation of the molecular sensor to quantum dots (QDs) was also investigated. The advantages and problems of FRET-based sensors are also discussed.