title: Eu3+-doped Gd2O3 nanoparticles as reporters for optical detection and visualization of antibodies patterned by microcontact printing.
abstract: Lanthanide oxide nanoparticles are promising luminescent probes in bioanalysis, because of their unique spectral properties, photostability, and low-cost synthesis. We report for the first time the application of europium-doped gadolinium oxide (Eu:Gd2O3) nanoparticles to the optical imaging of antibody micropatterns. The nanoparticles were synthesized by spray pyrolysis and coated with antibody (IgG) molecules by physical adsorption. Our experiments showed that the Eu:Gd2O3 is a good biocompatible solid support for antibody immobilization. The antibodies (anti-rabbit IgG) immobilized on the nanoparticles had excellent biological activity in the specific recognition reaction with rabbit IgG patterned in line strips (10 micromx10 microm) on a glass substrate by use of a micro-contact printing technique. The specific immunoreaction was confirmed by two independent microscopic techniques-fluorescence and scanning electron microscopy (SEM). Both microscopic images revealed that the nanoparticles were organized into designated structures as defined by the microcontact printing process with negligible non-specific binding. The nanoparticles can be used as fluorescent markers in a variety of immunosensing applications in a microscale format.
authors.affiliation: Department of Entomology, University of California Davis, One Shields Avenue, Davis, CA 95616, USA. mnichkova@ucdavis.edu
authors.forename: Mikaela
authors.initials: M
authors.lastname: Nichkova
authors.forename: Dosi
authors.initials: D
authors.lastname: Dosev
authors.forename: Richard
authors.initials: R
authors.lastname: Perron
authors.forename: Shirley J
authors.initials: SJ
authors.lastname: Gee
authors.forename: Bruce D
authors.initials: BD
authors.lastname: Hammock
authors.forename: Ian M
authors.initials: IM
authors.lastname: Kennedy
mesh_terms: D000327:Adsorption; D000906:Antibodies / Q000032:analysis / Q000737:chemistry*; D005063:Europium / Q000737:chemistry*; D005682:Gadolinium / Q000737:chemistry*; D008855:Microscopy, Electron, Scanning / Q000379:methods; D008856:Microscopy, Fluorescence / Q000379:methods; D053758:Nanoparticles / Q000737:chemistry*; D036103:Nanotechnology / Q000379:methods*; D055095:Optics and Photonics; D012680:Sensitivity and Specificity; D013499:Surface Properties
chemical_list: D000906:Antibodies; D005063:Europium; C030581:gadolinium oxide; D005682:Gadolinium