Proposed dissertation thesis presents novel hybrid electrochemical DNA biosensors based on distinct forms of pyrolytic graphite ("edge-plane" and "basal-plane") and their potential in terms of applicability in the field of DNA electrochemistry. Testing of the applicability of the presented bioanalytical tools was preceded by thorough optimization process involving selection of the optimal values for the most crucial operational parameters of the electrochemical DNA biosensors fabricated by means of electrostatic adsorption - deposition potential (Edep), deposition time (tdep), optimal DNA concentration for electrostatic adsorption (cg(DNA)), and possible involvement of convection during the adsorption procedure. Initially, applicability of presented bioanalytical tools was investigated in relation to monitoring DNA damage by utilization of triplet of external DNA damaging sources - UV light irradiation, one- electron oxidants, and hydroxy radicals. Outcome of the damaging processes was monitored directly (via monitoring changes in the redox signals of DNA) or indirectly (via monitoring changes in the redox signals of redox indicator) by the use of voltammetric methods - square- wave voltammetry (SWV), cyclic voltammetry (CV), linear-sweep voltammetry (LSV), and electrochemical impedance...
