title: The role of probe-probe interactions on the hybridization of double-stranded DNA targets onto DNA-modified magnetic microparticles.
abstract: In this work, we have studied the effect of different probe lengths and surface densities on the hybridization of a 181-bp polymerase chain reaction product to probes tethered onto magnetic microparticles. Hybridization was shown to be favored by longer probes but only at probe surface densities where probe-to-probe interactions are absent. From these results, a simple rule was inferred for determining maximum surface densities above which hybridization signals decreased. According to this rule, if the average surface area occupied by an immobilized probe (Sigma) is larger than the projected surface area of each tethered probe molecule (S(ss)), hybridization efficiency increases with surface density, whereas the reverse occurs when Sigma-S(ss) < 0.
authors.affiliation: IBB-Institute for Biotechnology and Bioengineering, Center for Biological and Chemical Engineering, Instituto Superior Técnico, Av. Rovisco Pais, 1049-001 Lisbon, Portugal.
authors.forename: S A M
authors.initials: SA
authors.lastname: Martins
authors.forename: D M F
authors.initials: DM
authors.lastname: Prazeres
authors.forename: L P
authors.initials: LP
authors.lastname: Fonseca
authors.forename: G A
authors.initials: GA
authors.lastname: Monteiro
mesh_terms: D004247:DNA / Q000032:analysis* / Q000235:genetics; D015342:DNA Probes / Q000032:analysis* / Q000235:genetics; D008280:Magnetics; D009693:Nucleic Acid Hybridization / Q000379:methods*; D013499:Surface Properties
chemical_list: D015342:DNA Probes; D004247:DNA