Quantitative Characterization of DNA Films by X-ray Photoelectron Spectroscopy

Abstract

We describe the use of self-assembled films of thiolated (dT)25 single-stranded DNA (ssDNA) on gold as a model system for quantitative characterization of DNA films by X-ray photoelectron spectroscopy (XPS). We evaluate the applicability of a uniform and homogeneous overlayer-substrate model for data analysis, examine model parameters used to describe DNA films (e.g., density and electron attenuation length), and validate the results. The model is used to obtain quantitative composition and coverage information as a function of immobilization time. We find that when the electron attenuation effects are properly included in theXPSdata analysis, excellent agreement is obtained with Fourier transform infrared (FTIR) measurements for relative values of the DNA coverage, and the calculated absolute coverage is consistent with a previous radiolabeling study. Based on the effectiveness of the analysis procedure for model (dT)25 ssDNA films, it should be generally valid for direct quantitative comparison of DNA films prepared under widely varying conditions.

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Document Details

Document Type
Technical Report
Publication Date
Sep 01, 2003
Accession Number
ADA482472

Entities

People

  • Dmitri Y. Petrovykh
  • Hiromi Kimura-suda
  • Lloyd J. Whitman
  • Michael J. Tarlov

Organizations

  • University of Maryland

Tags

Communities of Interest

  • Biomedical

DTIC Thesaurus Topics

  • Absorption
  • Band Gaps
  • Chemical Elements
  • Chemical Synthesis
  • Chemistry
  • Data Analysis
  • Electron Energy
  • Electrons
  • Energy Bands
  • Films
  • Kinetic Energy
  • Materials
  • Measurement
  • Photoelectrons
  • Self Assembled Monolayers
  • Spectroscopy
  • X Rays

Readers

  • Computational Modeling and Simulation
  • Molecular Genetics
  • Thin Film Deposition Science.

Technology Areas

  • Microelectronics
  • Microelectronics - Graphene