AVS 50th International Symposium
    Biomaterial Interfaces Wednesday Sessions
       Session BI-WeP

Paper BI-WeP11
Characterization of DNA Microarrays

Wednesday, November 5, 2003, 11:00 am, Room Hall A-C

Session: Poster Session
Presenter: D. Barbash, University of New Mexico
Authors: D. Barbash, University of New Mexico
J.E. Fulghum, University of New Mexico
Y. Wu, University of New Mexico
G.P. Lopez, University of New Mexico
Correspondent: Click to Email
DNA microarrays are widely used for gene expression studies. Production of DNA microarrays includes attachment of single stranded DNA or oligonucleotides onto a variety of different substrata. Methods that are used include directed synthesis of oligonucleotides by photolithography and printing pre-existing cDNA using precision robots. Substrates available for immobilization are gold, modified glasses (aminosilane or polylisine) and filter membranes. There are multiple functional groups in DNA that are capable of attachment the surface to the substrate. The purpose of our study is to reveal the chemistry behind DNA attachment to surfaces. We are using the ATMS(p-aminophenyl trimethoxy silane)/diazotization method to spot oligonucleotides on a microscope glass surface.(Dolan, P.L. et al. Nucleic Acids Research 2001, 29, 21e107). This method include immersion of cleaned microscope glass into the ATMS solution, its activation by NaCl and HCl and spotting DNA onto it. The method results in robust covalent attachment of the DNA in a manner that is compatible with subsequent hybridization.The methods for studying attached nucleotides include X-ray Photoelectron Spectroscopy (XPS) and Attenuated Total Reflection Spectroscopy (ATR-FTIR). XPS allow us characterize the surface composition from less than 10nm depth while ATR-FTIR technique provides chemical information from up to 1mm of the surface.