Protein A immunosensor for the detection of immunoglobulin G by impedance spectroscopy

DERKUŞ B., EMREGÜL K. C., MAZI H., EMREGÜL E., Yumak T., SINAĞ A.

BIOPROCESS AND BIOSYSTEMS ENGINEERING, vol.37, no.5, pp.965-976, 2014 (SCI-Expanded) identifier identifier identifier

  • Publication Type: Article / Article
  • Volume: 37 Issue: 5
  • Publication Date: 2014
  • Doi Number: 10.1007/s00449-013-1068-2
  • Journal Name: BIOPROCESS AND BIOSYSTEMS ENGINEERING
  • Journal Indexes: Science Citation Index Expanded (SCI-EXPANDED), Scopus
  • Page Numbers: pp.965-976
  • Keywords: Poly(maleicanhydride-alt-decene-1), TiO2 nanoparticle, Immunoglobulin G, Impedance spectroscopy, Immunosensor, DISPOSABLE ELECTROCHEMICAL IMMUNOSENSOR, BIOENGINEERING FUNCTIONAL COPOLYMERS, IMPEDIMETRIC IMMUNOSENSOR, ANTIBODY IMMOBILIZATION, SUPEROXIDE-DISMUTASE, NANOPARTICLES, TIO2, NANOCOMPOSITE, ELECTRODE, MATRIX
  • Ankara University Affiliated: Yes

Abstract

A novel highly sensitive electrochemical impedimetric Protein A immunosensor for the determination of immunoglobulin G (IgG) was developed by immobilization of Protein A within a newly synthesized, and characterized polymer, poly(maleicanhydride-alt-decene-1). TiO2 nanoparticles (10-30 nm) were synthesized, characterized with X-ray diffraction, transmission electron microscopy and Brunauer-Emmett-Teller surface analysis. The electron transfer between IgG and the poly(maleicanhydride-alt-decene-1)-TiO2-Protein A is quasireversible with a formal potential of 225 mV vs Ag|AgCl. The response of the poly(maleicanhydride-alt-decene-1)-TiO2-Protein A immunosensor was proportional to IgG concentration with a correlation coefficient of 0.9963. The detection limit and linear range was 0.57 ng mL(-1) and 0.0062-500 mu g mL(-1), respectively. Impedance measurments showed that synthesized TiO2 nanoparticles have better conducting properties compared with commercial degussa P25 TiO2 nanoparticles. The nonspecific binding of anti-MBP was 10 %. The label-free impedimetric immunosensor provided a simple and sensitive detection method for the specific determination of IgG in human serum.