A novel electrochemical impedance immunosensor for the quantification of CYFRA 21-1 in human serum

Aydın E. B., Aydın M., SEZGİNTÜRK M. K.

Microchimica Acta, vol.190, no.6, 2023 (SCI-Expanded) identifier identifier

  • Publication Type: Article / Article
  • Volume: 190 Issue: 6
  • Publication Date: 2023
  • Doi Number: 10.1007/s00604-023-05813-z
  • Journal Name: Microchimica Acta
  • Journal Indexes: Science Citation Index Expanded (SCI-EXPANDED), Scopus, Academic Search Premier, Aerospace Database, Analytical Abstracts, Aqualine, Aquatic Science & Fisheries Abstracts (ASFA), Biotechnology Research Abstracts, CAB Abstracts, Chemical Abstracts Core, Chimica, Communication Abstracts, EMBASE, Food Science & Technology Abstracts, MEDLINE, Metadex, Pollution Abstracts, Civil Engineering Abstracts
  • Keywords: Carbon black C45, Conjugated polymer, Disposable immunosensor, Indium tin oxide electrode, Label-free detection, Surface modified electrode
  • Çanakkale Onsekiz Mart University Affiliated: Yes


A sensitive, simple, and reliable immunosensor was constructed to detect the lowest alteration of a fragment of cytokeratin subunit 19 (CYFRA 21-1), a protein lung carcinoma biomarker. The proposed immunosensor was manufactured with a carbon black C45/polythiophene polymer-containing amino terminal groups (C45-PTNH2) conductive nanocomposite, resulting in an excellent, biocompatible, low-cost, and electrically conductive electrode surface. Anti-CYFRA 21-1 biorecognition molecules were attached to the electrode thanks to the amino terminal groups of the used PTNH2 polymer with a relatively simple procedure. All electrode surfaces after modifications were characterized by electrochemical, chemical, and microscopic techniques. Electrochemical impedance spectroscopy (EIS) was also utilized for the evaluation of the analytical feature of the immunosensor. The charge transfer resistance of the immunosensor signal was correlated with the CYFRA 21-1 concentration in the concentration range 0.03 to 90 pg/mL. The limit of detection (LOD) and the limit of quantification (LOQ) of the suggested system were 4.7 fg/mL and 14.1 fg/mL, respectively. The proposed biosensor had favorable repeatability and reproducibility, long storage stability, excellent selectivity, and low cost. Furthermore, it was applied to determine CYFRA 21-1 in commercial serum samples, and satisfactory recovery results (98.63–106.18%) were obtained. Thus, this immunosensor can be offered for clinical purposes as a rapid, stable, low-cost, selective, reproducible, and reusable tool. Graphical Abstract: [Figure not available: see fulltext.]