A Highly Selective Poly(thiophene)-graft-Poly(methacrylamide) Polymer Modified ITO Electrode for Neuron Specific Enolase Detection in Human Serum

Aydin M., AYDIN E. B., SEZGİNTÜRK M. K.

MACROMOLECULAR BIOSCIENCE, vol.19, no.8, 2019 (SCI-Expanded) identifier identifier identifier

  • Publication Type: Article / Article
  • Volume: 19 Issue: 8
  • Publication Date: 2019
  • Doi Number: 10.1002/mabi.201900109
  • Journal Name: MACROMOLECULAR BIOSCIENCE
  • Journal Indexes: Science Citation Index Expanded (SCI-EXPANDED), Scopus
  • Keywords: disposable electrodes, electrochemical impedance spectroscopy, graft polymer, lung cancer, neuron-specific enolase, FREE ELECTROCHEMICAL IMMUNOSENSOR, LABEL-FREE DETECTION, ULTRASENSITIVE DETECTION, SENSITIVE DETECTION, POLYACRYLAMIDE, IMMUNOASSAY, BIOSENSORS, IMPEDANCE, PROTEINS, ANTIBODY
  • Çanakkale Onsekiz Mart University Affiliated: Yes

Abstract

In this study, an impedimetric immunosensor based on polymer poly(thiophene)-graft-poly(methacrylamide) polymer (P(Thi-g-MAm)) modified indium tin oxide (ITO) electrode is developed for the detection of the Neuron Specific Enolase (NSE) cancer biomarker. First, the P(Thi-g-MAm) polymer is synthesized and coated on the ITO electrode by using a spin-coating technique. P(Thi-g-MAm) polymer acts as an immobilization platform for immobilization of NSE-specific monoclonal antibodies. Anti-NSE antibodies are utilized as biosensing molecules and they bind to the amino groups of P(Thi-g-Mam) polymer via glutaraldehyde cross-linking. Spin-coating technique is employed for bioelectrode fabrication and this technique provides a thin and uniform film on the ITO electrode surface. This bioelectrode fabrication technique is simple and it generates a suitable platform for large-scale loadings of anti-NSE antibodies. This immunosensor exhibits a wide linear detection range from 0.02 to 4 pg mL(-1) and with an ultralow detection limit of 6.1 fg mL(-1). It reveals a good long-term stability (after 8 weeks, 78% of its initial activity), an excellent reproducibility (1.29% of relative standard deviation (RSD)), a good repeatability (5.55% of RSD), and a high selectivity. In addition, the developed immunosensor is proposed as a robust diagnostic tool for the clinical detection of NSE and other cancer biomarkers.