| Abstract [eng] |
Protein aggregation in the human body is considered to be a key factor in the pathogenesis of neurodegenerative diseases such as Parkinson's and Alzheimer's. In order to develop effective therapies for the treatment and prevention of neurodegenerative diseases, there is a strong focus on aggregation studies of proteins, such as amyloid proteins, and on the search for substances that inhibit protein aggregation. In this work, new technique to determine lysozyme aggregate concentration in sample is developed. To create technique to determine lysozyme concentration, thioflavin T (ThT) oxidation on platinum electrode was used. Firstly, techniques to determine thioflavin T concentration in samples using cyclic voltammetry (CV) or electrochemical impedance spectroscopy (EIS) were developed. These methods than were investigated to being able to determine the concentrations of lysozyme aggregate in the samples. Using cyclic voltammetry to determine lysozyme aggregate concentration many measurements of different ThT concentrations were required. The calibration curve also included many measurements at different ThT concentrations. This method was able to identify lysozyme concentrations from 0.208 µM to 83.125 µM. To reduce the time taken for measurements, another method, to determine lysozyme concentration was developed. This method was based on the change in current intensity at 0.9 V at 849 µM ThT concentration. This method had the same linear concentration as past approach ranging from 0.208 µM to 83.125 µM. Determining lysozyme concentration using EIS method the results obtained were fitted using an equivalent circuit. Plotting charge transfer resistance against lysozyme aggregate concentration logarithm, the obtained linear concentration range is from 0.208 µM to 41.56 µM . |
