DISSERTATION

________________________________________________________________ Experimental Work
Synthesis of the acridine orange-glucose oxidase intercalator was done by Dr. Adrian Ruff
following procedures from Biver et al. 105 (for the modification of acridine orange) and
Schuhmann et al. 110 (for deglycosylation of glucose oxidase).
5.2 Electrochemical setup and instrumentation
All measurements were done in an electrochemical cell consisting of a polycrystalline gold
working electrode (2 mm diameter, CH Instruments, USA), a platinum auxiliary electrode
(Goodfellow, Germany) and a homemade Ag/AgCl (3 M KCl) or Pb/PbF2 (5 M KF) reference
electrode. Unless stated otherwise all electrochemical measurements were performed with an
Autolab PGSTAT302N containing a frequency response analyzer (Metrohm-Autolab,
Netherlands).
Figure 5.1. a) CV representing the deposition of PbF2 (2 nd cycle) performed at 20 mV/s in
0.5 M NaF solution. b) Picture of a home-made Pb/PbF2 reference electrode.
Preparation of the lead-lead fluoride reference electrode was done according to 81 . A ceramic
frit was introduced at the tip of a Pasteur pipette and the surrounding glass was melted to seal
it and prevent later electrolyte leakage. Subsequently, the tip was polished to expose the frit and
allow later ionic contact with the electrolyte solution. The pipette was filled with 5 M KF
solution and a piece of cotton was placed in the pipette construction to prevent clogging of the
electrode by detached PbF2. A lead wire was connected to a copper wire and the connection
110