We investigated the aggregation of Concanavalin A using infrared spectroscopy. Concanavalin A is a protein with a predominantly $\beta$-structure and has a very interesting way of aggregation. In acidic medium it aggregates in amorphous aggregates, whereas in alkaline medium it forms amyloid fibrils. Therefore, we have used it for testing retarding amyloids, which are the main cause of conformation diseases, such as Parkinson and Alzheimer disease. The growth of aggregates and amyloids was accelerated with the increase in temperature. We used two well-known inhibitors to slow down settled protein aggregates, which are homotavrine and resveratrol. We calculate sigmoid curves from structural changes taken from the analysis of amide I band and monitored the temperature of the transition from solution to aggregates, with and without inhibitors. Using the method of differential spectroscopy, we were able to accompany small structural changes, which are caused by temperature changes. The analysis spectrum is calculated as the difference between two spectra recorded at different temperatures. For this reason, this method allows us to look into spectral bands that are not the same for both spectra.
The temperature of the transition did not rise, as we had expected, with the increase in inhibitor concentration. Where it shows the increase, it correlates with the measurement error. There can be many reasons for this, it could be a wrong choice of concentration ratio, a saturated solution or my error with the solutions. Most of the problems with solving occurred with resveratrol, maybe it was not the best choice for the chosen concentration ratios.
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