Simultaneous amperometric immunosensing of the metastasis-related biomarkers IL-13Rα2 and CDH-17 by using grafted screen-printed electrodes and a composite prepared from quantum dots and carbon nanotubes for signal amplification

• Published in: Mikrochimica acta (1966) Vol. 186; no. 7; p. 411
• Main Authors: Serafín, Verónica, Valverde, Alejandro, Garranzo-Asensio, María, Barderas, Rodrigo, Campuzano, Susana, Yáñez-Sedeño, Paloma, Pingarrón, José M.
• Format: Journal Article
• Language: English
• Published: Vienna Springer Vienna 01.07.2019
• Subjects: Analytical Chemistry; Biomarkers, Tumor - analysis; Biosensing Techniques - methods; Cadherins - analysis; Cell Line, Tumor; Characterization and Evaluation of Materials; Chemistry; Chemistry and Materials Science; Electrochemical Techniques; Electrodes; Graphite - chemistry; Humans; Immobilized Proteins - chemistry; Immunoassay - methods; Interleukin-13 Receptor alpha2 Subunit - analysis; Limit of Detection; Microengineering; Nanochemistry; Nanotechnology; Nanotubes, Carbon - chemistry; Neoplasm Metastasis - diagnosis; Original Paper; Quantum Dots - chemistry; Sensitivity and Specificity; Metastasis-related biomarkers; Dual immunosensor; Graphene quantum dots; Colorectal cancer; Electrochemical immunosensor; Paraffin-embedded tissues; Signal amplification; Peroxidase mimic
• ISSN: 0026-3672; 1436-5073
• DOI: 10.1007/s00604-019-3531-5

This paper describes a dual electrochemical immunoassay for the simultaneous determination of IL-13Rα2 and CDH-17, two biomarkers of emerging relevance in metastatic processes. The sandwich assay uses a screen-printed dual carbon electrode that was electrochemically grafted with p-aminobenzoic acid to allow the covalent immobilization of capture antibodies. A hybrid composed of graphene quantum dots (GQDs) and multiwalled carbon nanotubes (MWCNTs) act as nanocarriers for the detection antibodies and horseradish peroxidase. The use of this hybrid material considerably improves the assay (in comparison to the use of MWCNTs) due to the peroxidase mimicking activity of the GQDs. The method works at a low working potential (0.20 V vs. Ag pseudo-reference electrode) and thus is not readily interfered by unknown electroactive species. The dual immunoassay allows for the selective determination of both biomarkers with LOD values of 1.4 (IL-13sRα2) and 0.03 ng mL −1 (CDH-17). The simultaneous determination of IL-13Rα2 and CDH-17 was accomplished in lysates from breast and colorectal cancer cells with different metastatic potential, and in paraffin-embedded tumor tissues extracts from patients diagnosed with colorectal cancer at different stages. The applicability to discriminate the metastatic potential even in intact cells through the detection of both extracellular receptors has been demonstrated also. The assay can be performed within 3 h, requires small sample amounts (0.5 μg), and has a simple protocol. Graphical abstract Dual amperometric immunosensing of the metastasis-related biomarkers IL-13Rα2 and CDH-17 in human colorectal cancer cells and tissues by using grafted screen-printed electrodes and composites of quantum dots and carbon nanotubes as nanocarriers.