INVESTIGADORES
TASSO Mariana Patricia
congresos y reuniones científicas
Título:
QUANTUM DOT-BASED CLUSTERS FUNCTIONALIZED FOR BIODETECTION
Autor/es:
DEMBELE, FATIMATA; TASSO, MARIANA; FRAGOLA, ALEXANDRA; LORIETTE, VINCENT; LEQUEUX, NICOLAS; PONS, THOMAS
Lugar:
Lille
Reunión:
Conferencia; E-MRS; 2016
Institución organizadora:
European Materials Research Society
Resumen:
Quantum dot (QD) semiconductor nanocrystals exhibit several unique properties that make them suitable candidates for biomolecular recognition. Not only do their narrow size-tunable emission spectra and broad excitation range allow multiplexed detection, but also these nanocrystals offer higher photostability and brightness as compared to conventional organic dyes. Recently, much interest has been paid to QD clusters because they show an increased and stable fluorescence signal as compared to single QDs, thus allowing an even greater sensitivity of detection. However, the process of assembling individual QDs, which are initially capped with hydrophobic ligands, into monodisperse colloidal aggregates can be tediouslaborious. Moreover, the hydrophilic shell of an ideal biomolecular probe must simultaneously fulfill several criteria by exhibiting robustness, low-fouling and facile (bio)functionalization. As a consequence, meeting all the requirements for the design of spherical, water-stable, low-fouling and (bio)functionalizable QD clusters remains a challenging task.Here, we describe the development of very compact fluorescent spherical nanosized clusters (NSCs) based on silica-embedded QDs envisioned as a tool for fast and sensitive biomolecular recognition. NSCs were obtained by self-assembling QDs into clusters of diameters around 130 nanometers in a cetyl trimethylammonium bromide-mediated microemulsion and by thereafter growing a silica shell on the clusters? surface by a Stöber-inspired process, giving rise to atypically compact QD-silica clusters. A new multidentate polymer-silane hybrid was synthesized, comprised of 2-methacryloyloxyethyl phosphorylcholine for water solubility, 3-(trimethoxysilyl) propyl methacrylate for silica anchoring and N-(11-azido-3,6,9-trioxaundecan)methacrylamide for conjugation with biomolecules. Stöber silica beads covered with this hybrid showed low-fouling properties (dynamic light scattering, bovine serum albumine non-specific absorption tests) and higher colloidal stability as compared to a monodentate silane in a physiological buffer. Once the polymer-silane hybrid was grafted onto the NSCs, its facile functionalization via copper-free bio-orthogonal cyclooctyne-azide click chemistry was demonstrated by a biotin-streptavidin affinity test.