Parabens are perservatives used in cosmetics, food and pharmaceuticals. Chemically they are alkyl esters of hydroxybenzoic acid. There are several different types of parabens, under different names, in our thesis we have chosen methylparaben (E218), ethylparaben (E214) and propylparaben (E216). We were interested in short-chain parabens, due to their higher ability to penetrate the skin compared to long-chain parabens. Most important pathways for parabens into organism are through the dygestive system and skin. Therefore we selected Caco-2, HepG2 and NCTC2544 cell lines to measure metabolism and permeability.
An HPLC (High Performance Liquid Chromatography) system was used for simultaneous detection of different compounds in samples. A sufficiently selective and sensitive metod was developed for this purpose.
The main metabolic pathway, restricting biological use of parabens, is the metabolism to para-hydroxybenzoic acid. Therefore, the ability to detect and quantify this conversion was tested in all cell lines. With theuse of Caco-2 cells the permeability properties of parabens and para-hydroxybenzoic acid were determined.
In this thesis, we observed how parabens are being transformed into metabolite, which is para-hydroxybenzoic acid, and came to conclusion that they are quick to enter membrane but as soon as they come into contact with membrane big flux of metabolite was noticed.
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