A Highly Sensitive Electrochemical Immunosensor for the detection of CCR4 Biomarker with Star-Shaped Polymer Covered Disposable Electrode

An electrochemical immunosensor prepared with the use of star-shaped polymer (StrPol(GMA)) as a biosensor matrix material was manufactured to quantify the CC chemokine receptor 4 (CCR4) molecules in human serum. Various characterization techniques, including electrochemical impedance spectroscopy (EIS), cyclic voltammetry (CV), and scanning electron microscopy (SEM), were used for the analysis of the fabrication steps of the proposed system. The impedance and CV analyses at each modification step of the manufacturing process illustrated the charge transport kinetics of the ferri-ferro redox solution. The binding of anti-CCR4 antibody and the related antibody-its CCR4 antigen biointeraction on the working electrode surface changed the interfacial electron transport. The interactions of anti-CCR4 with different levels of CCR4 were further followed via variations in impedance responses. The results illustrated that the electron transport resistance rose linearly with rising amounts of CCR4 antigen. The dynamic range and detection limit (LOD) were determined as 0.115-23 pg/mL and 34.9 fg/mL, respectively. The specificity, regeneration, storage stability, and reproducibility tests were also performed. Furthermore, CCR4 detection in the presence of interfering biomarkers was accomplished with success using the biosensing approach. The results of these studies illustrate that the introduced biosensor was a useful tool for monitoring low concentrations of CCR4 in human sera.