A nanostructured cerium oxide film-based immunosensor for mycotoxin detection

Nanotechnology. 2009 Feb 4;20(5):055105. doi: 10.1088/0957-4484/20/5/055105. Epub 2009 Jan 9.

Abstract

Rabbit-immunoglobulin antibodies (r-IgGs) and bovine serum albumin (BSA) have been immobilized onto sol-gel-derived nanostructured cerium oxide (nanoCeO(2)) film fabricated onto an indium-tin-oxide (ITO) coated glass plate to detect ochratoxin-A (OTA). Broad reflection planes obtained in x-ray diffraction (XRD) patterns reveal the formation of CeO(2) nanostructures. Electrochemical studies reveal that nanoCeO(2) particles provide an increased electroactive surface area for loading of r-IgGs with desired orientation, resulting in enhanced electron communication between r-IgGs and electrode. BSA/r-IgGs/nano CeO(2)/ITO immunoelectrode exhibits improved characteristics such as linear range (0.5-6 ng dl(-1)), low detection limit (0.25 ng dl(-1)), fast response time (30 s) and high sensitivity (1.27 microA ng(-1) dl(-1) cm(-2)). The high value of the association constant (K(a), 0.9 x 10(11) l mol(-1)) indicates the high affinity of the BSA/r-IgGs/nanoCeO(2)/ITO immunoelectrode to OTA.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Biosensing Techniques / instrumentation*
  • Cerium / chemistry*
  • Electrochemistry / instrumentation*
  • Equipment Design
  • Equipment Failure Analysis
  • Immunoassay / instrumentation*
  • Membranes, Artificial*
  • Microelectrodes*
  • Nanostructures / chemistry*
  • Nanostructures / ultrastructure
  • Ochratoxins / analysis*
  • Ochratoxins / chemistry

Substances

  • Membranes, Artificial
  • Ochratoxins
  • ochratoxin A
  • Cerium
  • ceric oxide