Construction of a novel immunoassay for the relationship between anxiety and the development of a primary immune response to adrenal cortical hormone
- 4 December 2004
- journal article
- clinical trial
- Published by Springer Science and Business Media LLC in Bioprocess and Biosystems Engineering
- Vol. 27 (2), 135-141
- https://doi.org/10.1007/s00449-004-0394-9
Abstract
A novel potentiometric immunosensor for the detection of adrenal cortical hormones (ACH) has been developed by means of self-assembling immobilization of adrenal cortical hormone antibody (anti-ACH) on a gold electrode-modified gold nanoparticle (Au) and a thiol-containing sol–gel network. A cleaned gold electrode was first immersed in a (3-mercaptopropyl)-trimethoxysilane (MPS) sol–gel solution to assemble a silica sol–gel monolayer, then the silane units were polymerized into a 2D sol–gel network (2D network) by dipping into aqueous NaOH. The second silane layer was formed by immersion back into the MPS solution overnight, and then the gold nanoparticles (nanogold) were chemisorbed onto the thiol groups of the second silane layer. Finally, anti-ACH was adsorbed onto the surface of the gold nanoparticles. The modified process was characterized by electrochemical impedance spectroscopy (EIS). The detection is based on the change in the potentiometric response before and after the antigen–antibody reaction. Using nanogold and 3-MPS as substrates, potentiometric detection at room temperature resulted in a pseudolinear detection range of about 22–1,000 ng mL−1 with a detection limit of 5.2 ng mL−1. Subsequently, several serum samples obtained from medical students with different anxiety extents were analyzed comparing with the ELISA method, and the results demonstrated that the immunoassay meets the demands of psychological analyses.Keywords
This publication has 13 references indexed in Scilit:
- Amplification of antigen–antibody interactions based on biotin labeled protein–streptavidin network complex using impedance spectroscopyBiosensors and Bioelectronics, 2001
- Surface Vibrational Spectroscopy of Alkylsilane Layers Covalently Bonded to Monolayers of (3-Mercaptopropyl)trimethoxysilane on Ag SubstratesLangmuir, 2000
- Immunosensors based on supported lipid membranes, protein films and liposomes modified by antibodiesSensors and Actuators B: Chemical, 1999
- A Potentiometric Microbial Biosensor for Direct Determination of Organophosphate Nerve AgentsElectroanalysis, 1998
- UNDERSTANDING INTERCELLULAR INTERACTIONS AND CELL ADHESION: LESSONS FROM STUDIES ON PROTEIN—METAL INTERACTIONSCell Biology International, 1997
- Capacitive monitoring of protein immobilization and antigen–antibody reactions on monomolecular alkylthiol films on gold electrodesBiosensors and Bioelectronics, 1997
- Investigation of Specific Binding of Antifluorescyl Antibody and Fab to Fluorescein Lipids in Langmuir-Blodgett Deposited Films Using Quartz Crystal Microbalance MethodologyAnalytical Chemistry, 1994
- Direct detection of biomolecules by electrochemical impedance measurementsSensors and Actuators B: Chemical, 1994
- Direct electron transfer at horseradish peroxidase—colloidal gold modified electrodesJournal of Electroanalytical Chemistry, 1992
- Controlled Nucleation for the Regulation of the Particle Size in Monodisperse Gold SuspensionsNature Physical Science, 1973