The following diploma thesis contains an overview of electrochemistry. Starting from common electroanalytical methods, potentiometric techniques are presented in detail. A thorough insight into the composition of binary carbon paste follows. There is also an introduction to the physical, chemical and electrochemical properties of carbon paste electrodes. This is followed by an overview of the production of carbon pastes, their characterization and processes at the carbon paste surface, in the carbon paste mass and the interaction between the above mentioned areas. Finally a short overview of modified carbon paste electrodes follows.
The optimization of the composition of the chemically modified paste and the measurement conditions by potentiometric quantification of the concentration of trihexyphenidylione reference solutions and tests of the analytical performance were the set goals of the following diploma thesis. By varying the ratio of the individual components (graphite, paste liquid, ion pair, graphene) we would have tried to achieve the appropriate composition of the paste. We would also have tried to use different paste liquids. Tests of the usable pH range and temperatures for the performance of the electrode would have been checked. The determination of the analytical performance would have included tests of response time, reproducibility, repeatability and limit of detection.
Due to the declared epidemic, only one paste of one composition (59.6% graphite, 39.5% dibutylphthalate, 0.9% trihexyphenidyltetraphenylborate) was prepared and appropriate measurements were made. Due to a lack of experience with the production of the paste and a too high graphite/paste liquid ratio, the paste proved to be unsuitable. This provides above all a theoretical overview of the experimental work set and the possibilities for further work.
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