DISSERTATION

_____________________________________________________________ Results and Discussion
Figure 3.53. Scheme of the characterization sequence: a) ssDNA immobilization (1 min,
0.5/-0.2 V pulse profile with 10 ms pulse duration); b) passivation with MCU (1 min, 0.5/-
0.2 V pulse profile with 10 ms pulse duration); c) hybridization with Fc-tDNA (10 min
incubation); d) dehybridization (H2O, 10 min); e) hybridization with a non-labelled tDNA
(10 min incubation); f) intercalation with AO-GOx (15 min, incubation) and detection of
the glucose oxidation current; g) dehybridization and removal of AO-GOx (H2O, ethanol,
~10 min); h) evaluation of the interaction of AO-GOx with ssDNA (15 min, incubation)
by amperometric detection. Chronoamperometric measurements were conducted at an
applied potential of +400 mV. FAD: flavin adenine dinucleotide. All potentials vs.
Ag/AgCl/3 M KCl; drawing not to scale.
In order to optimize DNA detection via the synthesized AO-GOx a thorough characterization
sequence was employed, which is presented in Figure 3.53. The DNA assay build-up consisted
of an initial ssDNA immobilization (Figure 3.53, a) followed by passivation of the surface with
MCU (Figure 3.53, b). The created DNA sensing platform was then subjected to hybridization
3.5 Intercalation as a DNA detection technique 99