title: Gold-coated carbon nanotube electrode arrays: Immunosensors for impedimetric detection of bone biomarkers.
abstract: C-terminal telopeptide (cTx), a fragment generated during collagen degradation, is a key biomarker of bone resorption during the bone remodeling process. The presence of varying levels of cTx in the bloodstream can hence be indicative of abnormal bone metabolism. This study focuses on the development of an immunosensor utilizing carbon nanotube (CNT) electrodes coated with gold nanoparticles for the detection of cTx, which could ultimately lead to the development of an inexpensive and rapid point-of-care (POC) tool for bone metabolism detection and prognostics. Electrochemical impedance spectroscopy (EIS) was implemented to monitor and detect the antigen-antibody binding events occurring on the surface of the gold-deposited CNT electrode. Type I cTx was used as the model protein to test the developed sensor. The sensor was accordingly characterized at various stages of development for evaluation of the optimal sensor performance. The biosensor could detect cTx levels as low as 0.05 ng/mL. The feasibility of the sensor for point-of-care (POC) applications was further demonstrated by determining the single frequency showing maximum changes in impedance, which was determined to be 18.75 Hz.
authors.affiliation: Department of Bioengineering, Swanson School of Engineering, University of Pittsburgh, Pittsburgh, PA, United States.
authors.forename: Madhumati
authors.initials: M
authors.lastname: Ramanathan
authors.affiliation: Department of Bioengineering, Swanson School of Engineering, University of Pittsburgh, Pittsburgh, PA, United States.
authors.forename: Mitali
authors.initials: M
authors.lastname: Patil
authors.affiliation: Department of Mechanical Engineering and Materials Science, Swanson School of Engineering, University of Pittsburgh, Pittsburgh, PA, United States.
authors.forename: Rigved
authors.initials: R
authors.lastname: Epur
authors.affiliation: Chemical and Bioengineering Department, North Carolina A&T State University, Greensboro, NC, United States.
authors.forename: Yeoheung
authors.initials: Y
authors.lastname: Yun
authors.affiliation: Department of Mechanical Engineering, University of Cincinnati, Cincinnati, OH, United States.
authors.forename: Vasselin
authors.initials: V
authors.lastname: Shanov
authors.affiliation: Department of Chemical and Materials Engineering, University of Cincinnati, Cincinnati, OH, United States.
authors.forename: Mark
authors.initials: M
authors.lastname: Schulz
authors.affiliation: Department of Chemistry, University of Cincinnati, Cincinnati, OH, United States.
authors.forename: William R
authors.initials: WR
authors.lastname: Heineman
authors.affiliation: Department of Bioengineering, Swanson School of Engineering, University of Pittsburgh, Pittsburgh, PA, United States.
authors.forename: Moni K
authors.initials: MK
authors.lastname: Datta
authors.affiliation: Department of Bioengineering, Swanson School of Engineering, University of Pittsburgh, Pittsburgh, PA, United States; Department of Mechanical Engineering and Materials Science, Swanson School of Engineering, University of Pittsburgh, Pittsburgh, PA, United States; Department of Chemical and Petroleum Engineering, Swanson School of Engineering, University of Pittsburgh, Pittsburgh, PA, United States; Department of Oral Biology, School of Dental Medicine, University of Pittsburgh, Pittsburgh, PA, United States. Electronic address: pkumta@pitt.edu.
authors.forename: Prashant N
authors.initials: PN
authors.lastname: Kumta
mesh_terms: D000818:Animals; D015415:Biomarkers / Q000378:metabolism; D001842:Bone and Bones / Q000378:metabolism*; D020099:Coated Materials, Biocompatible / Q000138:chemical synthesis; D024042:Collagen Type I / Q000378:metabolism*; D003217:Conductometry / Q000295:instrumentation*; D004867:Equipment Design; D019544:Equipment Failure Analysis; D006046:Gold / Q000737:chemistry*; D006801:Humans; D008839:Microelectrodes; D037742:Nanotubes, Carbon / Q000737:chemistry* / Q000648:ultrastructure; D010455:Peptides / Q000378:metabolism*; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D046888:Tissue Array Analysis / Q000295:instrumentation
chemical_list: D015415:Biomarkers; D020099:Coated Materials, Biocompatible; D024042:Collagen Type I; D037742:Nanotubes, Carbon; D010455:Peptides; C052929:collagen type I trimeric cross-linked peptide; D006046:Gold
keywords: Bone marker; C-terminal telopeptide; CNT; Gold nanoparticles; Immunosensor; Impedance