title: Avidin decorated core-shell nanoparticles for biorecognition studies by elastic light scattering.
abstract: In this paper, a straightforward method based on elastic light scattering is shown to provide a sensitive and reliable tool for the quantitative determination of protein-ligand interactions that occur at the surface of suitably designed core-shell nanoparticles. The assay makes use of monodisperse nanocolloids that have minimal optical contrast with the aqueous environment. By properly coating the particles with avidin and oligo(ethylene glycol)-based amphiphiles, we developed a hybrid system that combines the availability of standard ligands with the necessary bioinvisibility towards the accidental adsorption of nonspecific macromolecules. This probe was employed to detect interactions between different kinds of biotinylated proteins, and it revealed high specificity and affinities in the low nanomolar range. In particular, we obtained an efficient avidin anchorage of biotinylated protein A on the surface of the nanoparticles, which we exploited as a functional probe for the rapid, quantitative, picomolar detection of human IgG antibodies. Overall, these light-scattering-based nanosensors appear as a simple and highly informative tool for proteomics studies.
authors.affiliation: Istituto di Scienze e Tecnologie Molecolari, National Research Council (CNR), Via Golgi 19, 20133 Milano, Italy. davide.prosperi@unimi.it
authors.forename: Davide
authors.initials: D
authors.lastname: Prosperi
authors.forename: Carlo
authors.initials: C
authors.lastname: Morasso
authors.forename: Paolo
authors.initials: P
authors.lastname: Tortora
authors.forename: Diego
authors.initials: D
authors.lastname: Monti
authors.forename: Tommaso
authors.initials: T
authors.lastname: Bellini
mesh_terms: D000465:Algorithms; D001360:Avidin / Q000737:chemistry*; D001710:Biotin / Q000737:chemistry; D006801:Humans; D007074:Immunoglobulin G / Q000737:chemistry; D007202:Indicators and Reagents; D008024:Ligands; D008027:Light; D053758:Nanoparticles / Q000737:chemistry*; D012542:Scattering, Radiation
chemical_list: D007074:Immunoglobulin G; D007202:Indicators and Reagents; D008024:Ligands; D001360:Avidin; D001710:Biotin