title: Fabrication of DNA microarrays with poly(L-glutamic acid) monolayers on gold substrates for SPR imaging measurements.
abstract: Robust single-stranded DNA (ssDNA) microarrays are created by attaching amine-modified oligonucleotides to a monolayer of poly(L-glutamic acid) (pGlu) that is electrostatically adsorbed onto a chemically modified gold thin film. This surface attachment chemistry methodology is first characterized with a combination of polarization-modulation Fourier transform infrared (PM-FTIR) spectroscopy and surface plasmon resonance (SPR) angle shift measurements. SPR imaging (SPRI) measurements of these ssDNA microarrays are then used to study two surface bioaffinity interactions: (i) the quantitative hybridization adsorption of complementary ssDNA onto mixed ssDNA microarray elements and (ii) the adsorption of single-stranded binding protein (SSB) onto fully and partially hybridized DNA microarray elements. The Langmuir adsorption coefficient (K(Ads)) of SSB binding to ssDNA was determined to be (5.5 +/- 0.4) x 10(9) M(-1).
authors.affiliation: Department of Chemistry, University of California--Irvine, Irvine, California 92697, USA.
authors.forename: Yulin
authors.initials: Y
authors.lastname: Chen
authors.forename: Anh
authors.initials: A
authors.lastname: Nguyen
authors.forename: Lifang
authors.initials: L
authors.lastname: Niu
authors.forename: Robert M
authors.initials: RM
authors.lastname: Corn
mesh_terms: D000327:Adsorption; D006046:Gold / Q000737:chemistry*; D015394:Molecular Structure; D020411:Oligonucleotide Array Sequence Analysis / Q000295:instrumentation*; D011099:Polyglutamic Acid / Q000737:chemistry*; D017550:Spectroscopy, Fourier Transform Infrared; D020349:Surface Plasmon Resonance / Q000379:methods*; D013499:Surface Properties
chemical_list: D011099:Polyglutamic Acid; D006046:Gold