title: Electrochemical immunosensor for the analysis of the breast cancer biomarker HER2 ECD.
abstract: Human epidermal growth factor receptor 2 (HER2) is a breast cancer biomarker that plays a major role in promoting breast cancer cell proliferation and malignant growth. The extracellular domain (ECD) of HER2 can be shed into the blood stream and its concentration is measurable in the serum fraction of blood. In this work an electrochemical immunosensor for the analysis of HER2 ECD in human serum samples was developed. To achieve this goal a screen-printed carbon electrode, modified with gold nanoparticles, was used as transducer surface. A sandwich immunoassay, using two monoclonal antibodies, was employed and the detection of the antibody-antigen interaction was performed through the analysis of an enzymatic reaction product by linear sweep voltammetry. Using the optimized experimental conditions the calibration curve (ip vs. log[HER2 ECD]) was established between 15 and 100 ng/mL and a limit of detection (LOD) of 4.4 ng/mL was achieved. These results indicate that the developed immunosensor could be a promising tool in breast cancer diagnostics, patient follow-up and monitoring of metastatic breast cancer since it allows quantification in a useful concentration range and has an LOD below the established cut-off value (15 ng/mL).
authors.affiliation: REQUIMTE, Instituto Superior de Engenharia do Porto, Instituto Politécnico do Porto, Rua Dr. António Bernardino de Almeida 431, 4200-072 Porto, Portugal.
authors.forename: Raquel C B
authors.initials: RC
authors.lastname: Marques
authors.affiliation: Department of Industrial Chemistry, Alagappa University, Karaikudi-630003, Tamilnadu, India.
authors.forename: Subramanian
authors.initials: S
authors.lastname: Viswanathan
authors.affiliation: REQUIMTE, Instituto Superior de Engenharia do Porto, Instituto Politécnico do Porto, Rua Dr. António Bernardino de Almeida 431, 4200-072 Porto, Portugal. Electronic address: han@isep.ipp.pt.
authors.forename: Henri P A
authors.initials: HP
authors.lastname: Nouws
authors.affiliation: REQUIMTE, Instituto Superior de Engenharia do Porto, Instituto Politécnico do Porto, Rua Dr. António Bernardino de Almeida 431, 4200-072 Porto, Portugal.
authors.forename: Cristina
authors.initials: C
authors.lastname: Delerue-Matos
authors.affiliation: REQUIMTE, Instituto Superior de Engenharia do Porto, Instituto Politécnico do Porto, Rua Dr. António Bernardino de Almeida 431, 4200-072 Porto, Portugal.
authors.forename: M Begoña
authors.initials: MB
authors.lastname: González-García
mesh_terms: D000937:Antigen-Antibody Reactions; D014408:Biomarkers, Tumor / Q000097:blood*; D001943:Breast Neoplasms / Q000175:diagnosis*; D002138:Calibration; D002244:Carbon / Q000737:chemistry; D049109:Cell Proliferation; D004563:Electrochemistry / Q000379:methods*; D004566:Electrodes; D005260:Female; D006046:Gold / Q000737:chemistry; D006801:Humans; D007118:Immunoassay / Q000379:methods*; D057230:Limit of Detection; D053768:Metal Nanoparticles / Q000737:chemistry; D036103:Nanotechnology / Q000379:methods; D009362:Neoplasm Metastasis; D017434:Protein Structure, Tertiary; D018719:Erb-b2 Receptor Tyrosine Kinases / Q000097:blood*; D014159:Transducers
chemical_list: D014408:Biomarkers, Tumor; D002244:Carbon; D006046:Gold; D018719:Erb-b2 Receptor Tyrosine Kinases; C508053:ERBB2 protein, human
keywords: Breast cancer; Electrochemical immunosensor; Gold nanoparticles; HER2 ECD; Screen-printed carbon electrode