Students

Bc. level: 2016 - 2017
Supervisor: Karol Hensel
Title (en):
Cold plasma effects on biomolecules
Title (sk):
Účinky studenej plazmy na biomolekuly
Abstract (en)
Abstract (sk)

MSc. level: 2017 - 2019
Supervisor: Karol Hensel
Consultant: Katarína Kučerová
Title (en):
Effect of cold plasma generated by transient spark discharge on water solutions of proteins and amino acids
Title (sk):
Účinky studenej plazmy generovanej prechodovou iskrou na vodné roztoky proteínov a aminokyselín
Abstract (en):  hide
In this work, we focus on effects of cold non-equilibrium plasma generated by transient spark discharge in atmospheric pressure air on solutions of proteins and amino acids. Model protein, bovine serum albumin (BSA) and amino acids tryptophan (Trp) and tyrosine (Tyr) were dissolved in deionized water and treated in the cyclic system with different plasma exposure time. Our objective was to analyze effects of plasma on the solutions of protein and amino acids depending on their initial concentration and exposure time by UV-VIS and fluorescence spectroscopy. We also analyzed other effects (pH, temperature, formation of aggregates) in plasma treated solutions, that have been compared with calibration measurements without plasma. Changes in protein secondary structure were analyzed by circular dichroism (CD). The results showed effective protein denaturation by the plasma demonstrated by a significant decrease of absorbance and fluorescence of the solutions. Depending on input concentration of BSA, we observed different fluorescence shifts, effect of pH, formation of aggregates. For lower concentrations of BSA (15 μM), the dominant effect of cold plasma was decrease of pH and subsequent interaction of Trp with ions generated in the solution, which caused blue shift in fluorescence. For higher concentrations of BSA (480 μM), the dominant effect was denaturation of protein and therefore exposition of Trp buried in hydrophobic core of protein, which caused red shift in fluorescence and also formation of high amounts of aggregates. Results of CD measurements showed a decrease of helical content in protein secondary structure for concentration 15 μM, which verified interaction of Trp and ions in solution. This decrease was not observed for higher concentration of BSA. Beside many interesting results, further experiments are required for better understanding of plasma-protein interaction.
Abstract (sk)

PhD. level: 2019 - 2020
Supervisor: Marcela Morvová
Title (en):