DISSERTATION

_____________________________________________________________ Results and Discussion
3.4 Potential-assisted preparation of DNA sensors
Experiments for the optimization of the DNA sensing surface were done by Bianca Ciui under
the supervision of the author. Experiments with multi-electrode chips were performed together
with Yasin Uğur Kayran. Parts of the chapter are included in the manuscript that is in
preparation: “Fully potential-controlled preparation of DNA chips” with coauthors: D.
Jambrec, Y. U. Kayran and W. Schuhmann.
3.4.1 Optimization of the potential-pulse assisted immobilization method
Optimization of the potential-pulse assisted immobilization method to achieve highly
reproducible and very fast immobilization of intrinsically charged (DNA) or uncharged
molecules (thiols) provides a very efficient technique for preparation of DNA sensing
platforms, for which the desired ssDNA coverage and blocking ability can be reached within
minutes. Moreover, due to a very short modification time while maintaining a high level of
reproducibility and the ability to electrochemically remove undesired layers from the electrode
surface within seconds, the developed protocol has a potential for application in DNA array
production.
Figure 3.44. Scheme of the anchoring site used for immobilization of ssDNA.
Nevertheless, implementation of the developed technique into a DNA sensor or a DNA array
production requires further investigation. It is important to know whether the stability of a
3.4 Potential-assisted preparation of DNA sensors 85