title: Electrochemical microdevice with separable electrode and antibody chips for simultaneous detection of pepsinogens 1 and 2.
abstract: An electrochemical microdevice with separable electrode and antibody chips has been developed and applied to detect atrophic gastritis-related proteins, pepsinogen 1 (PG1) and pepsinogen 2 (PG2), based on sandwich-type enzyme-linked immunosorbent assays (ELISAs) with horseradish peroxidase (HRP)-labeled antibody. To fabricate the electrochemical device for simultaneous analysis of several proteins, the electrode chip with eight electrode elements was assembled along with an antibody chip with eight cavities containing immobilized anti-PG1 or anti-PG2. The immunoreactions occurring in the cavities of the device were detected simultaneously by amperometry. The labeled HRP in the cavity in the presence of hydrogen peroxide catalyzed the oxidation of ferrocenemethanol (FMA) to FMA+, which was detected electrochemically by the electrode chip. The amperometric responses of respective cavities in the device increased with increasing concentration of PG1 or PG2 of 0-50 ng/ml, ensuring the simultaneous detection of PG1 and PG2. The detection limits for both PG1 and PG2 were 0.6 ng/ml (S/N=2). The electrode chip was recovered easily by disassembling the electrochemical device; thereby, it was used repeatedly, whereas the antibody chip was discarded. No marked decrease in electrochemical responses was detected after repeated use. Reuse of the electrode chip is beneficial to reduce costs of protein analysis.
authors.affiliation: Graduate School of Environmental Studies, Tohoku University, 6-6-11 Aoba, Aramaki, Sendai 980-8579, Japan.
authors.forename: Daichi
authors.initials: D
authors.lastname: Ogasawara
authors.forename: Yu
authors.initials: Y
authors.lastname: Hirano
authors.forename: Tomoyuki
authors.initials: T
authors.lastname: Yasukawa
authors.forename: Hitoshi
authors.initials: H
authors.lastname: Shiku
authors.forename: Kiichirou
authors.initials: K
authors.lastname: Kobori
authors.forename: Koji
authors.initials: K
authors.lastname: Ushizawa
authors.forename: Shohei
authors.initials: S
authors.lastname: Kawabata
authors.forename: Tomokazu
authors.initials: T
authors.lastname: Matsue
mesh_terms: D000906:Antibodies / Q000032:analysis / Q000276:immunology; D015374:Biosensing Techniques / Q000295:instrumentation* / Q000379:methods; D004563:Electrochemistry / Q000295:instrumentation* / Q000379:methods; D004797:Enzyme-Linked Immunosorbent Assay / Q000295:instrumentation* / Q000379:methods; D004867:Equipment Design; D019544:Equipment Failure Analysis; D056656:Lab-On-A-Chip Devices; D046208:Microchip Analytical Procedures / Q000379:methods; D008839:Microelectrodes; D008904:Miniaturization; D020116:Pepsinogen A / Q000032:analysis* / Q000276:immunology; D020115:Pepsinogen C / Q000032:analysis* / Q000276:immunology
chemical_list: D000906:Antibodies; D020115:Pepsinogen C; D020116:Pepsinogen A