A separation-free amperometric immunosensor for vitellogenin based on screen-printed carbon arrays modified with a conductive polymer

Biosens Bioelectron. 2005 Mar 15;20(9):1780-7. doi: 10.1016/j.bios.2004.07.006.

Abstract

A disposable amperometric immunosensor was studied for the rapid detection of carp (Carassius auratus) Vitellogenin (Vtg). The sensor was fabricated based on screen-printed carbon arrays (SPCAs) containing eight carbon working and an integrated carbon counter electrodes. To construct the sensor, a conducting polymer (poly-terthiophene carboxylic acid) was electropolymerized on the surface of working electrodes and the polymer-coated SPCAs was characterized by SEM. Horseradish peroxidase (HRP) and a monoclonal antibody (anti-Vtg) specific to carp Vtg were covalently attached onto the polymer modified SPCAs. The immobilization of HRP and anti-Vtg onto the polymer-coated SPCAs was examined using cyclic voltammetry and quartz crystal microbalance studies. In order to detect the amount of Vtg, glucose oxidase (GOx)-labelled Vtg bound to the sensor surface under competition with the Vtg analyte was quantified amperometrically using glucose as a substrate. The performance of the eight sensors in arrays was evaluated by obtaining the calibration plots for Vtg. The sensor arrays exhibit a linear range of the Vtg concentration from 0.25 to 7.8 ng/ml and the detection limit was determined to be 0.09 ng/ml. Furthermore, the performance of the immunosensor for the determination of Vtg was evaluated by a standard addition method performed in fish serum samples.

Publication types

  • Evaluation Study
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Biomarkers / blood
  • Biosensing Techniques / instrumentation
  • Biosensing Techniques / methods*
  • Blood Chemical Analysis / instrumentation
  • Blood Chemical Analysis / methods*
  • Carbon / chemistry
  • Carps / blood*
  • Coated Materials, Biocompatible / chemistry
  • Electric Conductivity
  • Electrochemistry / instrumentation
  • Electrochemistry / methods*
  • Electrodes*
  • Female
  • Immunoassay / instrumentation
  • Immunoassay / methods*
  • Male
  • Materials Testing
  • Polymers / chemistry
  • Surface Properties
  • Vitellogenins / blood*
  • Vitellogenins / immunology
  • Water Pollutants, Chemical / blood

Substances

  • Biomarkers
  • Coated Materials, Biocompatible
  • Polymers
  • Vitellogenins
  • Water Pollutants, Chemical
  • Carbon