title: Ultrasensitive Nanoimmunosensor by coupling non-covalent functionalized graphene oxide platform and numerous ferritin labels on carbon nanotubes.
abstract: An ultrasensitive electrochemical nanostructured immunosensor for a breast cancer biomarker carbohydrate antigen 15-3 (CA 15-3) was fabricated using non-covalent functionalized graphene oxides (GO/Py-COOH) as sensor probe and multiwalled carbon nanotube (MWCNTs)-supported numerous ferritin as labels. The immunosensor was constructed by immobilizing a monoclonal anti-CA 15-3 antibody on the GO modified cysteamine (Cys) self-assembled monolayer (SAM) on an Au electrode (Au/Cys) through the amide bond formation between the carboxylic acid groups of GO/Py-COOH and amine groups of anti-CA 15-3. Secondary antibody conjugated MWCNT-supported ferritin labels (Ab2-MWCNT-Ferritin) were prepared through the amide bond formation between amine groups of Ab2 and ferritin and carboxylic acid groups of MWCNTs. The detection of CA 15-3 was based on the enhanced bioelectrocatalytic reduction of hydrogen peroxide mediated by hydroquinone (HQ) at the GO/Py-COOH-based sensor probe. The GO/Py-COOH-based sensor probe and Ab2-MWCNT-Ferritin labels were characterized using cyclic voltammetry (CV), electrochemical impedance spectroscopy (EIS), scanning electron microscope (SEM), transmission electron microscope (TEM), and x-ray photoelectron spectroscopy (XPS) techniques. Using differential pulse voltammetry (DPV) technique, CA 15-3 can be selectively detected as low as 0.01 ± 0.07 U/mL in human serum samples. Additionally, the proposed CA 15-3 immunosensor showed excellent selectivity and better stability in human serum samples, which demonstrated that the proposed immunosensor has potentials in proteomic researches and diagnostics.
authors.affiliation: Graduate School of Analytical Science and Technology, Chungnam National University, Daejeon 34134, South Korea.
authors.forename: Rashida
authors.initials: R
authors.lastname: Akter
authors.affiliation: Graduate School of Analytical Science and Technology, Chungnam National University, Daejeon 34134, South Korea.
authors.forename: Bongjin
authors.initials: B
authors.lastname: Jeong
authors.affiliation: Graduate School of Analytical Science and Technology, Chungnam National University, Daejeon 34134, South Korea; Division of Life Science, Korea Basic Science Institute, Daejeon 34133, South Korea.
authors.forename: Jong-Soon
authors.initials: JS
authors.lastname: Choi
authors.affiliation: Graduate School of Analytical Science and Technology, Chungnam National University, Daejeon 34134, South Korea. Electronic address: marahman@cnu.ac.kr.
authors.forename: Md Aminur
authors.initials: MA
authors.lastname: Rahman
mesh_terms: D014408:Biomarkers, Tumor / Q000235:genetics / Q000302:isolation & purification*; D015374:Biosensing Techniques; D001943:Breast Neoplasms / Q000175:diagnosis* / Q000473:pathology; D055664:Electrochemical Techniques; D005293:Ferritins / Q000737:chemistry; D006108:Graphite / Q000737:chemistry; D006801:Humans; D006861:Hydrogen Peroxide / Q000737:chemistry; D057230:Limit of Detection; D053768:Metal Nanoparticles / Q000737:chemistry; D018396:Mucin-1 / Q000235:genetics / Q000302:isolation & purification*; D037742:Nanotubes, Carbon / Q000737:chemistry*; D010087:Oxides / Q000737:chemistry; D040901:Proteomics
chemical_list: D014408:Biomarkers, Tumor; D018396:Mucin-1; D037742:Nanotubes, Carbon; D010087:Oxides; D006108:Graphite; D005293:Ferritins; D006861:Hydrogen Peroxide
keywords: Carbohydrate antigen 15-3; Electrochemical immunosensor; Ferritin; Graphene oxide; Multiwalled carbon nanotube