title: Electrochemical multianalyte immunoassays using an array-based sensor.
abstract: A novel amperometric biosensor for performing simultaneous electrochemical multianalyte immunoassays is described. The sensor consisted of eight iridium oxide sensing electrodes (0.78 mm(2) each), an iridium counter electrode, and a Ag/AgCl reference electrode patterned on a glass substrate. Four different capture antibodies were immobilized on the sensing electrodes via adsorption. Quantification of proteins was achieved using an ELISA in which the electrochemical oxidation of enzyme-generated hydroquinone was measured. The spatial separation of the electrodes enabled simultaneous electrochemical immunoassays for multiple proteins to be conducted in a single assay without amperometric cross-talk between the electrodes. The simultaneous detection of goat IgG, mouse IgG, human IgG, and chicken IgY was demonstrated. The detection limit was 3 ng/mL for all analytes. The sensor had excellent precision (1.9-8.2% interassay CV) and was comparable in performance to commercial single-analyte ELISAs. We anticipate that chip-based sensors, as described herein, will be suitable for the mass production of economical, miniaturized, multianalyte assay devices.
authors.affiliation: EIC Laboratories, Inc., 111 Downey Street, Norwood, Massachusetts 02062, USA. mwilson@eiclabs.com
authors.forename: Michael S
authors.initials: MS
authors.lastname: Wilson
authors.forename: Weiyan
authors.initials: W
authors.lastname: Nie
mesh_terms: D000818:Animals; D015374:Biosensing Techniques / Q000295:instrumentation / Q000379:methods*; D002645:Chickens; D004563:Electrochemistry; D004566:Electrodes; D006041:Goats; D006801:Humans; D006873:Hydroquinones / Q000032:analysis* / Q000737:chemistry; D007118:Immunoassay / Q000379:methods*; D007074:Immunoglobulin G / Q000032:analysis* / Q000276:immunology; D007136:Immunoglobulins / Q000032:analysis* / Q000276:immunology; D007495:Iridium / Q000737:chemistry; D051379:Mice; D010084:Oxidation-Reduction; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D012834:Silver / Q000737:chemistry; D018030:Silver Compounds / Q000737:chemistry
chemical_list: D006873:Hydroquinones; C016512:IgY; D007074:Immunoglobulin G; D007136:Immunoglobulins; D018030:Silver Compounds; D012834:Silver; D007495:Iridium; C037548:silver chloride