title: Tunable control of antibody immobilization using electric field.
abstract: The controlled immobilization of proteins on solid-state surfaces can play an important role in enhancing the sensitivity of both affinity-based biosensors and probe-free sensing platforms. Typical methods of controlling the orientation of probe proteins on a sensor surface involve surface chemistry-based techniques. Here, we present a method of tunably controlling the immobilization of proteins on a solid-state surface using electric field. We study the ability to orient molecules by immobilizing IgG molecules in microchannels while applying lateral fields. We use atomic force microscopy to both qualitatively and quantitatively study the orientation of antibodies on glass surfaces. We apply this ability for controlled orientation to enhance the performance of affinity-based assays. As a proof of concept, we use fluorescence detection to indirectly verify the modulation of the orientation of proteins bound to the surface. We studied the interaction of fluorescently tagged anti-IgG with surface immobilized IgG controlled by electric field. Our study demonstrates that the use of electric field can result in more than 100% enhancement in signal-to-noise ratio compared with normal physical adsorption.
authors: Department of Electrical Engineering and Computer Sciences, University of California, Berkeley, CA 94720; Stanford Genome Technology Center, Stanford School of Medicine, Palo Alto, CA 94304; sam.e@berkeley.edu mehdi.javanmard@rutgers.edu jeanne.thompson@stanford.edu.
authors: Sam
authors: S
authors: Emaminejad
authors: Department of Electrical and Computer Engineering, Rutgers University, Piscataway, NJ 08854; and sam.e@berkeley.edu mehdi.javanmard@rutgers.edu jeanne.thompson@stanford.edu.
authors: Mehdi
authors: M
authors: Javanmard
authors: Department of Electrical Engineering, Stanford University, Stanford, CA 94305.
authors: Chaitanya
authors: C
authors: Gupta
authors: Department of Electrical Engineering, Stanford University, Stanford, CA 94305.
authors: Shuai
authors: S
authors: Chang
authors: Stanford Genome Technology Center, Stanford School of Medicine, Palo Alto, CA 94304; sam.e@berkeley.edu mehdi.javanmard@rutgers.edu jeanne.thompson@stanford.edu.
authors: Ronald W
authors: RW
authors: Davis
authors: Department of Electrical Engineering, Stanford University, Stanford, CA 94305.
authors: Roger T
authors: RT
authors: Howe
mesh_terms: D000906:Antibodies / Q000737:chemistry*; D004560:Electricity; D007074:Immunoglobulin G / Q000737:chemistry*; D018625:Microscopy, Atomic Force; D013050:Spectrometry, Fluorescence
chemical_list: D000906:Antibodies; D007074:Immunoglobulin G
keywords: electrokinetic; microfluidics; protein assay; protein immobilization; sample preparation
references: Proc Natl Acad Sci U S A. 2014 Feb 11;111(6):2110-5
references: 24449893
references: Anal Biochem. 2003 Jan 15;312(2):113-24
references: 12531195
references: Proc Natl Acad Sci U S A. 2006 Oct 3;103(40):14773-8
references: 17001006
references: Nano Lett. 2005 Jan;5(1):119-24
references: 15792424
references: Biosens Bioelectron. 2009 Sep 15;25(1):253-8
references: 19665685
references: Biophys J. 1993 Dec;65(6):2428-36
references: 8312481
references: J Chem Phys. 2004 Jul 8;121(2):1050-7
references: 15260639
references: J Biotechnol. 2000 Jan 21;76(2-3):207-14
references: 10656335
references: Phys Rev E Stat Nonlin Soft Matter Phys. 2007 Jan;75(1 Pt 1):011503
references: 17358156
references: Phys Rev E Stat Nonlin Soft Matter Phys. 2009 Jan;79(1 Pt 1):011402
references: 19257030
references: Curr Opin Chem Biol. 2003 Feb;7(1):55-63
references: 12547427
references: Lab Chip. 2009 May 21;9(10):1429-34
references: 19417910
references: Proc Natl Acad Sci U S A. 2008 Dec 30;105(52):20637-40
references: 19074273
references: Nano Lett. 2010 Mar 10;10(3):1070-5
references: 20141183
references: Nat Biotechnol. 2008 Apr;26(4):417-26
references: 18392027
references: Nano Lett. 2005 Jan;5(1):5-9
references: 15792403
references: J Am Chem Soc. 2010 Mar 31;132(12):4388-92
references: 20192199
references: Biosens Bioelectron. 2009 Jan 1;24(5):1109-15
references: 18656344