Surface plasmon resonance-based DNA microarrays: Comparison of thiol and phosphorothioate modified oligonucleotides

K. L. Jimenez-Monroy*, A. Kick, K. Eersels, B. van Grinsven, P. Wagner, M. Mertig

*Corresponding author for this work

Research output: Contribution to journalArticleAcademicpeer-review

3 Citations (Web of Science)

Abstract

We present the use of thiol-modified and phosphorothioate (PT)-modified oligonucleotides for building DNA microarrays on the gold surface of surface plasmon resonance (SPR) chips. PT-modified oligonucleotides (PTOs) have several advantages in comparison to thiol-modified ones. They do not form disulfides and the PT groups can be introduced in any desired position of the molecular backbone of the oligonucleotide. Additionally, modifications with PT groups are not as cost-intensive as thiol groups. The direct immobilization of the oligonucleotides via thiol and PT groups is compared. The affinity of the PT groups to gold is lower than that of thiol groups. Nevertheless, the hybridization kinetics of a model polymerase chain reaction (PCR) product could be studied in real time on a DNA microarray for both types of modified oligonucleotides. This contributes to clarification of previous, contradictory reports on the use of PTOs for their attachment to gold surfaces. The immobilization of PTOs could be improved by the introduction of iodoacetylated surfaces, which are reactive to bind PTs as well as thiols with high efficiency. Furthermore, the influence of the probe structure on the probe density and the hybridization was investigated.

Original languageEnglish
Pages (from-to)918-925
Number of pages8
JournalPhysica Status Solidi A-applications and Materials Science
Volume210
Issue number5
DOIs
Publication statusPublished - May 2013
Externally publishedYes

Keywords

  • DNA chip
  • DNA hybridization
  • microarray
  • phosphorothioate
  • surface plasmon resonance
  • thiol
  • SINGLE-STRANDED-DNA
  • AU NANOPARTICLES
  • GOLD SURFACES
  • HYBRIDIZATION
  • IMMOBILIZATION
  • PROBES
  • SPECTROSCOPY
  • ATTACHMENT
  • BIOSENSOR
  • SENSORS

Cite this