title: Negative dielectrophoresis spectroscopy for rare analyte quantification in biological samples.
abstract: We propose the use of negative dielectrophoresis (DEP) spectroscopy as a technique to improve the detection limit of rare analytes in biological samples. We observe a significant dependence of the negative DEP force on functionalized polystyrene beads at the edges of interdigitated electrodes with respect to the frequency of the electric field. We measured this velocity of repulsion for 0% and 0.8% conjugation of avidin with biotin functionalized polystyrene beads with our automated software through real-time image processing that monitors the Rayleigh scattering from the beads. A significant difference in the velocity of the beads was observed in the presence of as little as 80 molecules of avidin per biotin functionalized bead. This technology can be applied in the detection and quantification of rare analytes that can be useful in the diagnosis and the treatment of diseases, such as cancer and myocardial infarction, with the use of polystyrene beads functionalized with antibodies for the target biomarkers.
authors.affiliation: North Dakota State University, Electrical and Computer Engineering Department, Fargo, North Dakota, United StatesbCOMSATS Institute of Information Technology, Center for Advanced Studies in Telecommunication, Islamabad, Pakistan.
authors.forename: Syed Abdul Mannan
authors.initials: SA
authors.lastname: Kirmani
authors.affiliation: North Dakota State University, Electrical and Computer Engineering Department, Fargo, North Dakota, United States.
authors.forename: Fleming Dackson
authors.initials: FD
authors.lastname: Gudagunti
authors.affiliation: North Dakota State University, Electrical and Computer Engineering Department, Fargo, North Dakota, United States.
authors.forename: Logeeshan
authors.initials: L
authors.lastname: Velmanickam
authors.affiliation: North Dakota State University, Electrical and Computer Engineering Department, Fargo, North Dakota, United States.
authors.forename: Dharmakeerthi
authors.initials: D
authors.lastname: Nawarathna
authors.affiliation: North Dakota State University, Electrical and Computer Engineering Department, Fargo, North Dakota, United States.
authors.forename: Ivan T
authors.initials: IT
authors.lastname: Lima
mesh_terms: D015415:Biomarkers / Q000032:analysis*; D002623:Chemistry Techniques, Analytical / Q000295:instrumentation* / Q000379:methods*; D004566:Electrodes; D004586:Electrophoresis; D057230:Limit of Detection; D011137:Polystyrenes / Q000737:chemistry; D013057:Spectrum Analysis
chemical_list: D015415:Biomarkers; D011137:Polystyrenes