Design of an Affibody-Based Recognition Strategy for Human Epidermal Growth Factor Receptor 2 (HER2) Detection by Electrochemical Biosensors

Abstract

Abstract:In this study, we have designed and realized three simple electrochemical bioassays for the detection of the human epidermal growth factor receptor 2 (HER2) cancer biomarker using magnetic beads coupling screen-printed arrays. The different approaches were based on a sandwich format in which affibody (Af) or antibody (Ab) molecules were coupled respectively to streptavidin or protein A-modified magnetic beads. The bioreceptor-modified beads were used to capture the HER2 protein from the sample and sandwich assay was performed by adding the labeled secondary affibody or the antibody. An enzyme-amplified detection scheme based on the coupling of secondary biotinylated bioreceptor with streptavidin-alkaline phosphatase enzyme conjugate was then applied. The enzyme catalyzed the hydrolysis of the electro-inactive 1-naphthyl-phosphate to the electro-active 1-naphthol, which was detected by means of differential pulse voltammetry (DPV). Each developed assay has been studied and optimized. Furthermore, a thorough comparison of the analytical performances of developed assays was performed. Finally, preliminary experiments using serum samples spiked with HER2 protein were also carried out.

Electrochemical Biosensing in Cancer Diagnostics and Follow‐up

“…Ilkhani et al [23] reported three simple magnetic bead-based approaches, combined with screen-printed arrays, for the analysis of HER2. The bioassays were based on a sandwich format in which affibody (Af) or antibody molecules were immobilized on streptavidin-or protein A-modified MBs (Strept-MBs or Prot A-MBs).…”

Electrochemical Sensing Platforms for HER2‐ECD Breast Cancer Biomarker Detection

“…Although in label-free assays the analysis times are shorter than in the sandwich-type assays, the time required for the electrode surface modification and subsequent incubation of the capture antibody is considerably higher. From the comparison of the analytical performances of the immunomagnetic assays [14][15][16][17][18] with the immunosensors [10,11,13,19] can be concluded that when magnetic beads are used as sensing platform, shorter linear ranges and slightly lower LODs were obtained. This indicates that the use of magnetic particles and the detection strategy optimized in this work is promising.…”

“…Furthermore, the use of nanomaterials, with excellent and reliable physicochemical properties, in the sensor's construction increases the electrode's surface area with a subsequent increase of sensitivity [12]. Al-Khafaji et al and Ilkhani et al used magnetic beads functionalized with Protein A to improve the affinity interaction between the biomolecules and to construct faster electrochemical bioassays [16,17]. Pre-synthesized AuNPs were grown on the MWCNT-CILE surface through electrodeposition, to form AuNP/MWCNT-CILE, which is a suitable surface for antibody attachment [13].…”

“…Efficient bioconjugation is largely achieved by using magnetic particles comprising a magnetite core (Fe 3 O 4 MNPs) with a non-magnetic coating [5]. Al-Khafaji et al and Ilkhani et al used magnetic beads functionalized with Protein A to improve the affinity interaction between the biomolecules and to construct faster electrochemical bioassays [16,17]. Eletxigerra et al developed a magnetoimmunosensor based on carboxylic acid-modified magnetic beads.…”

Electrochemical Immunosensors and Aptasensors

“…Marrazza and coworkers [14] propose the use of affibodies immobilized on magnetic particles to detect, with screen printed electrodes, the human epidermal growth factor receptor 2 (HER2) which is overexpressed by breast cancer cells. De Wael et al [15] study the immobilization of aptamers on core-shell nanoparticles for improving the electrochemical detection of bacteria.…”