Due to improper waste management, the amount of plastic waste in the environment is increasing significantly. Because of the various environmental processes, these plastics disintegrate into smaller particles, collectively known as microplastics.
Among them, the detection and determination of the type of microplastic present in the environment stands out. Research in this field has only expanded in recent years, therefore there is still a continuous development of new, innovative, more affordable, and faster methods for detection of microplastics.
In the master’s thesis, we focused on the use of an electrochemical method, namely cyclic voltammetry. In the method, with the help of an electrochemical probe (potassium ferricyanide/ferrocyanide), an electric potentiostat and an electrode, we stimulate redox reactions and check the change of electric current depending on the voltage. To execute the experimental work, we used screen printed electrodes, the surface of which was previously modified with mesoporous silica and proline. Successfully modified electrodes were then exposed to samples with a suspension of microplastics, a suspension of beech dust and a blank sample. Results showed that microplastics bound to the working surface of the electrode and filled the pores. With this, microplastics interrupted or weakened the contact between the electrode and the electrochemical probe, therefore the course of redox reactions was inhibited and consequently the current response of the electrode decreased. We also concluded that if the electrode is exposed to a suspension of beech dust or a blank sample, there are no differences in the electric current response. In addition to qualitative analysis, we also investigated the possibility of quantitative analysis. Thus, we exposed the modified electrodes to different concentrations of microplastic suspensions and reached results that imply to the potential possibility of using the electrochemical method also for the purpose of quantitative analysis.
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