title: A label-free electrochemical affisensor for cancer marker detection: The case of HER2.
abstract: In this paper, we report the development of a sensitive label-free impedimetric biosensor based on the use of affibody as bioreceptor and gold nanostructured screen-printed graphite as a sensor platform for the detection of human epidermal growth factor receptor 2 (HER2). The affisensor is realized by immobilizing a terminal cysteine-modified affibody on gold nanoparticles. The sensor was characterized by electrochemical techniques and scanning electron microscopy (SEM). Furthermore, surface plasmon resonance (SPR) technology was also applied to explore the potential of affibodies as small-molecule discriminating tools. Using optimized experimental conditions, a single-use affisensor showed a good analytical performance for HER2 detection from 0 to 40 μg/L. The estimated limit of detection was 6.0 μg/L. Finally, the realized affisensor was applied to human serum samples.
authors.affiliation: Department of Chemistry "Ugo Schiff", University of Florence, Via della Lastruccia 3, 50019 Sesto Fiorentino, Florence, Italy. Electronic address: andrea.ravalli@unifi.it.
authors.forename: Andrea
authors.initials: A
authors.lastname: Ravalli
authors.affiliation: Department of Chemistry "Ugo Schiff", University of Florence, Via della Lastruccia 3, 50019 Sesto Fiorentino, Florence, Italy; Department of Analytical Chemistry, São Paulo State University (UNESP), Rua Prof. Francisco Degni 55, 14800-060 Araraquara, SP, Brazil. Electronic address: carolgomesrocha@hotmail.com.
authors.forename: Carolina Gomes
authors.initials: CG
authors.lastname: da Rocha
authors.affiliation: Department of Analytical Chemistry, São Paulo State University (UNESP), Rua Prof. Francisco Degni 55, 14800-060 Araraquara, SP, Brazil. Electronic address: hidekoy@iq.unesp.br.
authors.forename: Hideko
authors.initials: H
authors.lastname: Yamanaka
authors.affiliation: Department of Chemistry "Ugo Schiff", University of Florence, Via della Lastruccia 3, 50019 Sesto Fiorentino, Florence, Italy. Electronic address: giovanna.marrazza@unifi.it.
authors.forename: Giovanna
authors.initials: G
authors.lastname: Marrazza
mesh_terms: D055910:Antibodies, Immobilized; D014408:Biomarkers, Tumor / Q000032:analysis* / Q000097:blood; D015374:Biosensing Techniques / Q000295:instrumentation / Q000379:methods*; D055664:Electrochemical Techniques; D004566:Electrodes; D004867:Equipment Design; D006046:Gold / Q000737:chemistry; D006108:Graphite / Q000737:chemistry; D006801:Humans; D008855:Microscopy, Electron, Scanning; D053758:Nanoparticles / Q000737:chemistry; D009369:Neoplasms / Q000097:blood / Q000175:diagnosis; D018719:Erb-b2 Receptor Tyrosine Kinases / Q000032:analysis* / Q000097:blood / Q000276:immunology; D020349:Surface Plasmon Resonance
chemical_list: D055910:Antibodies, Immobilized; D014408:Biomarkers, Tumor; D006046:Gold; D006108:Graphite; D018719:Erb-b2 Receptor Tyrosine Kinases; C508053:ERBB2 protein, human
keywords: Affibody; Biosensor; HER2; Nanoparticle; Tumor marker