ac070358e_si_001.pdf (34.33 kB)
Electrochemical Detection of DNA Hybridization via Bis-Intercalation of a Naphthylimide-Functionalized Viologen Dimer
journal contribution
posted on 2007-09-15, 00:00 authored by Eli G. Hvastkovs, Daniel A. ButtryThe synthesis and DNA binding properties of a bis-naphthyl imide tetracationic diviologen compound NI(CH2)3V2+(CH2)6V2+(CH2)3NI (where V2+ = 4,4‘-bipyridinium and NI = naphthyl imide, NIV) are described.
Binding to thiolated ssDNA and dsDNA immobilized at
Au electrodes was characterized using the electrochemical
response for reduction of the V2+ state to the V+ (viologen
radical cation) state. Isotherms and binding constants for
this molecule to both forms of immobilized DNA were
generated in this fashion. The character of the binding
isotherm for dsDNA suggests bis-intercalation. Under
high saline conditions, the diviologen molecule dissociated 160 times slower from dsDNA compared to ssDNA.
Slow dissociation kinetics from dsDNA (kd =7.0 × 10-5
s-1) allow this molecule to be used as an effective DNA
hybridization indicator.