Meritve permeabilnosti sestavin eteričnih olj skozi kožo prašičjega uhlja in vitro

Smodiš, Sindy (avtor), Žakelj, Simon (mentor)

Koža je naš največji in najtežji organ, njena najpomembnejša naloga je barierna funkcija, ki jo zagotavlja rožena plast. Če je barierna funkcija oslabljena, sta absorpcija tujih snovi in izguba lastnih (predvsem vode) skozi kožo povečani, kar ni zaželeno. Permeabilnost spojin skozi kožo določamo in vitro ali in vivo. Najpogostejša je metoda in vitro z uporabo Franzovih difuzijskih celic, ki ni etično sporna v primerjavi z nekaterimi metodami in vivo. Namen diplomske naloge je bil določiti permeabilnost petih pogostih sestavin eteričnih olj (kafre, linaloola, mentola, linalilacetata in 1,8-cineola). Poskus smo izvedli v Franzovih celicah na koži prašičjega uhlja, vzorčili pa smo v okviru 24-ur. Za analizo vzorcev smo si izbrali plinsko kromatografijo, pri čemer smo sprva uporabili detektor FID. Po izvedbi predposkusa se je izkazalo, da detektor FID ni dovolj občutljiv, da bi po poskusu in vitro zaznali prisotnost izbranih spojin v akceptorskem mediju. Zato smo nadaljnje meritve opravljali z bolj občutljivo sklopljeno metodo plinske kromatografije z masno spektrometrijo. Ker je akceptorska raztopina na osnovi fosfatnega pufra s primesmi, zaradi katerih niso mogoče direktne meritve s plinsko kromatografijo, smo morali razviti ustrezen postopek ekstrakcije, ki je moral imeti čim boljši in ponovljiv izkoristek. Da smo lahko preverili, ali oleinska kislina izboljša permeabilnost izbranim sestavinam eteričnih olj, smo uporabili tudi dva različna donorska medija. Ugotovili smo, da s plinsko kromatografijo z detektorjem FID ni bilo mogoče zaznati nobene izbrane spojine, medtem ko smo s sklopljeno metodo plinske kromatografije z masno spektrometrijo nekatere zaznali. Vse testirane spojine so zelo slabo permeabilne. Največjo permeabilnost ima kafra, sledila sta 1,8-cineol in linalool ter nazadnje mentol. Linalilacetata nismo uspeli zaznati v nobeni akceptorski raztopini, zato predvidevamo, da ni prehajal kožne bariere oziroma njegovo prehajanje ni bilo biološko relevantno. Pri celicah s prisotno oleinsko kislino smo videli majhno povečanje permeabilnosti pri vseh spojinah, vendar te razlike niso bile statistično značilne.

• Jezik: Slovenski jezik
• Ključne besede: sestavine eteričnih olj, Franzova difuzijska celica, plinska kromatografija, permeabilnost, prašičja koža
• Vrsta gradiva: Diplomsko delo/naloga
• Organizacija: FFA - Fakulteta za farmacijo
• Leto izida: 2019
• PID: 20.500.12556/RUL-106822
• Datum objave v RUL: 18.03.2019

Sekundarni jezik

• Jezik: Angleški jezik
• Naslov: Permeability measurements of the essential oil constituents through porcine ear skin in vitro

Izvleček

The skin is human’s largest and heaviest organ. Its most important function is as a barrier towards the external environment, which is made possible by the stratum corneum. If the barrier function is weakened, the absorption of foreign compounds and the loss of water through the skin are increased, which is not desired. Permeability of compounds through the skin is determined in vitro or in vivo. Most frequently an in vitro method utilizing the Franz diffusion chambers is used, since it is not ethically controversial in comparison to some other in vivo methods. The aim of this thesis is to determine the permeability of five common essential oil constituents (camphor, linalool, menthol, linalyl acetate and 1,8-cineole). The experiment was conducted in Franz diffusion chambers with porcine ear skin. The sampling was done in a 24-hour window. For sample analysis our first choice was gas chromatography with FID detector. The pilot experiment showed that a more sensitive detection of the selected compounds in the extracts of the acceptor medium will be necessary. We therefore continued with a gas chromatography coupled with a mass spectrometer. An additional step of extraction was needed, since a hydrophilic medium a phosphate buffered saline with an additive for enhancing the sink conditions was necessary in acceptor fluid, in which the direct gas chromatography measurements are not possible. A high and repeatable recovery of the sample extraction process was necessary. We also tested if oleic acid improves permeability of the selected compounds, so we performed the tests with two different donor media. In conclusion, gas chromatography with FID detector was not able to detect any of the selected compounds in acceptor solutions, while gas chromatography coupled with a mass spectrometer did, but not all of them were permeable enough for quantification. All tested compounds exhibited very low permeability. Among them the highest permeability belonged to camphor, followed by 1,8-cineole, linalool and menthol. We were not able to determine linalyl acetate in any of the acceptor medium samples, leading us to a conclusion, that it does not cross the skin barrier in a significant amount. We noticed a slight but statistically insignificant increase in permeability when oleic acid was present in the donor medium.

• Ključne besede: essential oil compounds, Franz diffusion cell, gas chromatography, permeability, porcine ear skin