title: A Highly Sensitive Immunosorbent Assay Based on Biotinylated Graphene Oxide and the Quartz Crystal Microbalance.
abstract: A high-sensitivity flow-based immunoassay is reported based on a gold-coated quartz crystal microbalance (QCM) chip functionalized directly in the QCM without requiring covalent conjugation steps. Specifically, the irreversible adsorption of a biotinylated graphene oxide-avidin complex followed by loading of a biotinylated capture antibody is applied to avoid more complex conventional surface modification chemistries and enable chip functionalization and sensing all within the QCM instrument. The resulting immunosensors exhibit significantly lower nonspecific protein adsorption and stronger signal for antigen sensing relative to simple avidin-coated sensors. Reproducible quantification of rabbit IgG concentrations ranging from 0.1 ng/mL to 10 μg/mL (6 orders of magnitude) can be achieved depending on the approach used to quantify the binding with simple mass changes used to detect higher concentrations and a horseradish peroxidase-linked detection antibody that converts its substrate to a measurable precipitate used to detect very low analyte concentrations. Sensor fabrication and assay performance take ∼5 h in total, which is on par with or faster than other techniques. Quantitative sensing is possible in the presence of complex protein mixtures, such as human plasma. Given the broad availability of biotinylated capture antibodies, this method offers both an easy and flexible platform for the quantitative sensing of a variety of biomolecule targets.
authors.affiliation: Department of Chemical Engineering, McMaster University , Hamilton, Ontario L8S 4L7, Canada.
authors.forename: Xudong
authors.initials: X
authors.lastname: Deng
authors.affiliation: Department of Biochemistry and Biomedical Sciences, McMaster University , Hamilton, Ontario L8S 4L8, Canada.
authors.forename: Mengsu
authors.initials: M
authors.lastname: Chen
authors.affiliation: Department of Chemical Engineering, McMaster University , Hamilton, Ontario L8S 4L7, Canada.
authors.forename: Qiang
authors.initials: Q
authors.lastname: Fu
authors.affiliation: Department of Chemical Engineering, McMaster University , Hamilton, Ontario L8S 4L7, Canada.
authors.forename: Niels M B
authors.initials: NM
authors.lastname: Smeets
authors.affiliation: Department of Chemical Engineering, McMaster University , Hamilton, Ontario L8S 4L7, Canada.
authors.forename: Fei
authors.initials: F
authors.lastname: Xu
authors.affiliation: Department of Chemical Engineering, McMaster University , Hamilton, Ontario L8S 4L7, Canada.
authors.forename: Zhuyuan
authors.initials: Z
authors.lastname: Zhang
authors.affiliation: Department of Chemical Engineering, McMaster University , Hamilton, Ontario L8S 4L7, Canada.
authors.forename: Carlos D M
authors.initials: CD
authors.lastname: Filipe
authors.affiliation: Department of Chemical Engineering, McMaster University , Hamilton, Ontario L8S 4L7, Canada.
authors.forename: Todd
authors.initials: T
authors.lastname: Hoare
mesh_terms: D000327:Adsorption; D000818:Animals; D000906:Antibodies / Q000737:chemistry; D001360:Avidin; D019921:Biotinylation; D002138:Calibration; D006046:Gold / Q000737:chemistry; D006108:Graphite / Q000737:chemistry*; D006801:Humans; D007118:Immunoassay / Q000379:methods*; D007164:Immunosorbents / Q000737:chemistry*; D008855:Microscopy, Electron, Scanning; D056951:Photoelectron Spectroscopy; D058525:Quartz Crystal Microbalance Techniques / Q000379:methods*; D017550:Spectroscopy, Fourier Transform Infrared; D013499:Surface Properties; D013997:Time Factors
chemical_list: D000906:Antibodies; D007164:Immunosorbents; D001360:Avidin; D006046:Gold; D006108:Graphite
keywords: biotinylation; graphene oxide; immunoassay; quartz crystal microbalance