title: Electrochemical immunosensing using micro and nanoparticles.
abstract: A model immunosensor based on a labeling method using gold nanoparticles (AuNPs) and electrochemical detection is developed. Microparamagnetic beads (MB) as primary antibody immobilization platforms and AuNPs modified with a secondary antibody as high sensible electrochemical labels have been used. The carbon electrode used as transducer incorporates a magnet that allows the collection/ immobilization on its surface of the immunological sandwich attached to the MB. Briefly, the sandwich type assay consists in the incubation of streptavidin-coupled-MB with an antihuman IgG biotin conjugate, and then, the immunological reaction with the human IgG antigen takes place. After that, a gold labeled anti-human IgG reacts with the antigen, and finally the AuNPs are electrochemically detected. This approach allows the obtaining of an immunosensor with a low antigen detection limit with special interest for several applications in protein analysis.
authors.affiliation: Nanobioelectronics & Biosensors Group, Institut Català de Nanotecnologia, Barcelona, Catalonia, Spain.
authors.forename: Alfredo
authors.initials: A
authors.lastname: de la Escosura-Muñiz
authors.forename: Adriano
authors.initials: A
authors.lastname: Ambrosi
authors.forename: Salvador
authors.initials: S
authors.lastname: Alegret
authors.forename: Arben
authors.initials: A
authors.lastname: Merkoçi
mesh_terms: D015374:Biosensing Techniques / Q000295:instrumentation* / Q000379:methods; D004563:Electrochemistry / Q000295:instrumentation*; D004867:Equipment Design; D019544:Equipment Failure Analysis; D007118:Immunoassay / Q000295:instrumentation*; D007074:Immunoglobulin G / Q000032:analysis*; D008839:Microelectrodes; D008863:Microspheres; D053758:Nanoparticles / Q000737:chemistry* / Q000648:ultrastructure; D036103:Nanotechnology / Q000295:instrumentation* / Q000379:methods; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity
chemical_list: D007074:Immunoglobulin G