title: Fast and sensitive detection of an anthrax biomarker using SERS-based solenoid microfluidic sensor.
abstract: We report the application of a fully automated surface-enhanced Raman scattering (SERS)-based solenoid-embedded microfluidic device to the quantitative and sensitive detection of anthrax biomarker poly-γ-D-glutamic acid (PGA) in solution. Analysis is based on the competitive reaction between PGA and PGA-conjugated gold nanoparticles with anti-PGA-immobilized magnetic beads within a microfluidic environment. Magnetic immunocomplexes are trapped by yoke-type solenoids embedded within the device, and their SERS signals were directly measured and analyzed. To improve the accuracy of measurement process, external standard values for PGA-free serum were also measured through use of a control channel. This additional measurement greatly improves the reliability of the assay by minimizing the influence of extraneous experimental variables. The limit of detection (LOD) of PGA in serum, determined by our SERS-based microfluidic sensor, is estimated to be 100 pg/mL. We believe that the defined method represents a valuable analytical tool for the detection of anthrax-related aqueous samples.
authors.affiliation: Department of Bionano Technology, Hanyang University, Ansan 426-791, South Korea.
authors.forename: Rongke
authors.initials: R
authors.lastname: Gao
authors.affiliation: Department of Bionano Technology, Hanyang University, Ansan 426-791, South Korea.
authors.forename: Juhui
authors.initials: J
authors.lastname: Ko
authors.affiliation: Division of High-Risk Pathogen Research, Center for Infectious Diseases, National Institute of Health, Cheongju 363-951, South Korea.
authors.forename: Kiweon
authors.initials: K
authors.lastname: Cha
authors.affiliation: Division of High-Risk Pathogen Research, Center for Infectious Diseases, National Institute of Health, Cheongju 363-951, South Korea.
authors.forename: Jun Ho
authors.initials: JH
authors.lastname: Jeon
authors.affiliation: Division of High-Risk Pathogen Research, Center for Infectious Diseases, National Institute of Health, Cheongju 363-951, South Korea.
authors.forename: Gi-eun
authors.initials: GE
authors.lastname: Rhie
authors.affiliation: Department of Bionano Technology, Hanyang University, Ansan 426-791, South Korea.
authors.forename: Jonghoon
authors.initials: J
authors.lastname: Choi
authors.affiliation: Department of Chemistry and Applied Biosciences, Institute of Chemical and Bioengineering, ETH Zürich, Vladimir Prelog Weg 1, 8093 Zürich, Switzerland. Electronic address: andrew.demello@chem.ethz.ch.
authors.forename: Andrew J
authors.initials: AJ
authors.lastname: deMello
authors.affiliation: Department of Bionano Technology, Hanyang University, Ansan 426-791, South Korea. Electronic address: jbchoo@hanyang.ac.kr.
authors.forename: Jaebum
authors.initials: J
authors.lastname: Choo
mesh_terms: D000881:Anthrax / Q000097:blood / Q000175:diagnosis*; D055910:Antibodies, Immobilized / Q000737:chemistry; D001408:Bacillus anthracis / Q000302:isolation & purification*; D004867:Equipment Design; D006046:Gold / Q000737:chemistry; D006801:Humans; D007118:Immunoassay / Q000191:economics / Q000295:instrumentation; D057230:Limit of Detection; D053768:Metal Nanoparticles / Q000737:chemistry; D044085:Microfluidics / Q000191:economics / Q000295:instrumentation*; D011099:Polyglutamic Acid / Q000031:analogs & derivatives* / Q000032:analysis / Q000097:blood; D015203:Reproducibility of Results; D013059:Spectrum Analysis, Raman / Q000295:instrumentation*
chemical_list: D055910:Antibodies, Immobilized; C511775:poly(gamma-glutamic acid); D011099:Polyglutamic Acid; D006046:Gold
keywords: Anthrax; Microfluidics; Poly-γ-d-glutamic acid; Solenoid; Surface-enhanced Raman scattering