IUVSTA 15th International Vacuum Congress (IVC-15), AVS 48th International Symposium (AVS-48), 11th International Conference on Solid Surfaces (ICSS-11)
    Biomaterials Monday Sessions
       Session BI-MoP

Paper BI-MoP14
Competitive Oligonucleotide Adsorption Equilibria at a Silane-Water Interface

Monday, October 29, 2001, 5:30 pm, Room 134/135

Session: Biorecognition Poster Session
Presenter: A.D. Suseno, Zyomyx, Inc.
Authors: A.D. Suseno, Zyomyx, Inc.
R.S. Gascon, Zyomyx, Inc.
J.L. DelosReyes, Zyomyx, Inc.
J.E. Forman, Zyomyx, Inc.
Correspondent: Click to Email
Adsorption of complimentary oligonucleotide sequences to surface bound oligonucleotide probes can produce surface bound duplex structures that are more prone to dissociation than their solution phase counterparts. The stability (as indicated by the observed melting temperature or Tm) can be altered by a number of factors, including probe orientation on the surface and surface bound probe density. A bound orientation that does not allow the probe to fully interact with its complimentary sequence can result in a non-optimal (and thus lower stability) duplex structure. Such effects are expected when immobilized probes are bound through exo-cyclic amines or crosslinking of thymidine residues to the surface. For surface bound probe densities, crowded surfaces that limit the amount of bound target through unfavorable steric and/or electrostatic interactions serve to destabilize the surface bound duplexes. Likewise, surfaces that interact with the immobilized probe, will compete with adsorption of complimentary sequences and can ultimately reduce duplex stability. Yet, despite these potential hindrances to duplex formation, surface bound probes can adsorb complimentary sequences from solutions in which those sequences are present in double stranded form (where the second strand is non-complimentary to the surface bound probes). We will present results from experiments in which covalently immobilized oligonucleotide probes on silanated substrates interact with both single- and double-stranded oligonucleotide target sequences to illustrate consequences of surface immobilization strategy, as well as what effect the introduction of a competing solution phase duplex formation equilibria has on adsortion to the surface bound probes.