title: Bead-based immunoassays using a micro-chip flow cytometer.
abstract: A microfabricated flow cytometer has been developed for the analysis of micron-sized polymer beads onto which fluorescently labelled proteins have been immobilised. Fluorescence measurements were made on the beads as they flowed through the chip. Binding of antibodies to surface-immobilised antigens was quantitatively assayed using the device. Particles were focused through a detection zone in the centre of the flow channel using negative dielectrophoresis. Impedance measurements of the particles (at 703 kHz) were used to determine particle size and to trigger capture of the fluorescence signal. Antibody binding was measured by fluorescence at single and dual excitation wavelengths (532 nm and 633 nm). Fluorescence compensation techniques were implemented to correct for spectral overspill between optical detection channels. The data from the microfabricated flow cytometer was shown to be comparable to that of a commercial flow cytometer (BD-FACSAria).
authors.affiliation: School of Electronics and Computing Science, University of Southampton, Highfield, Southampton, UK SO17 1BJ. dh2@ecs.soton.ac.uk
authors.forename: David
authors.initials: D
authors.lastname: Holmes
authors.forename: Joseph K
authors.initials: JK
authors.lastname: She
authors.forename: Peter L
authors.initials: PL
authors.lastname: Roach
authors.forename: Hywel
authors.initials: H
authors.lastname: Morgan
mesh_terms: D000818:Animals; D000906:Antibodies / Q000032:analysis; D004852:Epoxy Compounds / Q000737:chemistry; D005434:Flow Cytometry / Q000295:instrumentation / Q000379:methods*; D005456:Fluorescent Dyes / Q000737:chemistry; D006801:Humans; D007118:Immunoassay / Q000295:instrumentation / Q000379:methods; D007074:Immunoglobulin G / Q000276:immunology; D008689:Methacrylates / Q000737:chemistry; D046210:Microfluidic Analytical Techniques / Q000295:instrumentation / Q000379:methods*; D008863:Microspheres; D011817:Rabbits
chemical_list: D000906:Antibodies; D004852:Epoxy Compounds; D005456:Fluorescent Dyes; D007074:Immunoglobulin G; D008689:Methacrylates; C007870:glycidyl methacrylate