Preparation of screen-printed electrochemical immunosensors for estradiol, and their application in biological fluids.
The method of fabrication of a prototype electrochemical immunosensor for estradiol (E2) is described. Methodologies are also given for colorimetric assays, which can be used to verify and optimize reagent performance, prior to their use in the electrochemical immunoassay: these include an E2 ELISA and a colorimetric assay performed on the immunosensor surface. The electrochemical immunosensor system uses screen-printed carbon electrodes (SPCEs) upon which antibody against E2 is immobilized. Antibodies (rabbit anti-mouse IgG, then monoclonal mouse anti-E2) are immobilized by passive adsorption onto the working electrode surface. A competitive immunoassay is then performed using an alkaline-phosphatase-labeled E2 conjugate. Electrochemical measurements are performed using differential pulse voltammetry (DPV) to detect the production of 1-naphthol from 1-naphthyl phosphate. The calibration plot of DPV peak current vs. E2 concentration shows a measurable range of 25-500 pg/mL with a detection limit of 50 pg/mL. The immunosensor can be applied to the determination of E2 in spiked serum, following an extraction step with diethyl ether.
Pemberton
Roy M
RM
Faculty of Health and Life Sciences, University of the West of England, Bristol, UK.
Hart
John P
JP
D000818:Animals; D015374:Biosensing Techniques / Q000295:instrumentation* / Q000379:methods; D001774:Blood Chemical Analysis / Q000295:instrumentation* / Q000379:methods; D001826:Body Fluids / Q000737:chemistry*; D004563:Electrochemistry / Q000295:instrumentation* / Q000379:methods; D004867:Equipment Design; D019544:Equipment Failure Analysis; D004958:Estradiol / Q000097:blood*; D007118:Immunoassay / Q000295:instrumentation* / Q000379:methods; D008839:Microelectrodes; D011817:Rabbits; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity
D004958:Estradiol