title: AC dielectrophoretic manipulation and electroporation of vaccinia virus using carbon nanoelectrode arrays.
abstract: This paper reports the capture and detection of vaccinia virus particles based on AC dielectrophoresis (DEP) and electrochemical impedance measurements employing an embedded vertically aligned carbon nanofiber (VACNF) nanoelectrode array (NEA) versus a macroscopic indium-tin-oxide (ITO) transparent electrode in a "points-and-lid" configuration. The nano-DEP device was fabricated by bonding two SU-8 covered electrodes patterned using photolithography. The bottom electrode contains a 200 × 200 μm2active region on a randomly distributed NEA and the top electrode contains a microfluidic channel in SU-8 spin-coated on ITO to guide the flow of the virus solution. The real-time impedance change was measured during DEP capture and validated with fluorescence microscopy measurements. The NEA was able to capture virus particles with a rather low AC voltage (∼8.0 V peak-to-peak) at 1.0 kHz frequency as the particles were passed through the fluidic channel at high flow velocities (up to 8.0 mm/s). A concentration detection limit as low as ∼2.58 × 103particles/mL was obtained via impedance measurements after only 54 sec of DEP capture. At the low AC frequencies (50.0 Hz or less), the high electric field at the exposed VACNF tips induced electroporation of the DEP-captured virus particles, which was validated by fluorescence emission from the dyes staining lipophilic membrane and internal nucleic acid, respectively. This study suggests the possibility of integration of a fully functional electronic device for rapid, reversible and label-free capture and detection of pathogenic viruses, with a potential of generating electroporation to the captured the virus particles for further biochemical study.
authors.affiliation: Department of Physical Sciences, Embry-Riddle Aeronautical University, Daytona Beach, FL, USA.|Department of Chemistry, Kansas State University, Manhattan, KS, USA.
authors.forename: Foram Ranjeet
authors.initials: FR
authors.lastname: Madiyar
authors.affiliation: Department of Pathology, University of Texas Medical Branch, Galveston, TX, USA.
authors.forename: Sherry L
authors.initials: SL
authors.lastname: Haller
authors.affiliation: Department of Physical Sciences, Embry-Riddle Aeronautical University, Daytona Beach, FL, USA.
authors.forename: Omer
authors.initials: O
authors.lastname: Farooq
authors.affiliation: Department of Medical Microbiology and Immunology, School of Medicine, the University of California at Davis, Davis, CA, USA.
authors.forename: Stefan
authors.initials: S
authors.lastname: Rothenburg
authors.affiliation: Department of Chemistry, Kansas State University, Manhattan, KS, USA.
authors.forename: Christopher
authors.initials: C
authors.lastname: Culbertson
authors.affiliation: Department of Chemistry, Kansas State University, Manhattan, KS, USA.|College of Chemistry and Chemical Engineering, Hubei Normal University, Huangshi, P. R. China.
authors.forename: Jun
authors.initials: J
authors.lastname: Li
mesh_terms: D002244:Carbon; D003198:Computer Simulation; D017097:Electric Impedance; D004566:Electrodes; D004586:Electrophoresis / Q000379:methods*; D018274:Electroporation / Q000379:methods*; D004867:Equipment Design / Q000295:instrumentation / Q000379:methods; D005456:Fluorescent Dyes; D056656:Lab-On-A-Chip Devices; D057230:Limit of Detection; D046228:Microarray Analysis; D008839:Microelectrodes; D008856:Microscopy, Fluorescence; D008962:Models, Theoretical; D057139:Nanofibers; D036103:Nanotechnology; D017971:Tin Compounds / Q000737:chemistry; D014616:Vaccinia virus / Q000302:isolation & purification*
chemical_list: D005456:Fluorescent Dyes; D017971:Tin Compounds; C109984:indium tin oxide; D002244:Carbon
keywords: Dielectrophoresis; Electroporation; Microfluidic; Nanoelectrode array; Real-time impedance; Vaccinia virus; Vertically aligned carbon nanofibers