Naslov
Application of Fick’ s law of diffusion to determine the skin permeability

Autori
Jakasa, Ivone ; Kezic, Sanja

Vrsta, podvrsta i kategorija rada
Sažeci sa skupova, sažetak, znanstveni

Izvornik
XXI. Hrvatski skup kemičara i kemijskih inženjera - Knjiga sažetaka / Novak, Predrag - Zagreb : Hrvatsko društvo kemijskih inženjera i tehnologa (HDKI) ; Hrvatsko kemijsko drustvo, 2009, 162-162

ISBN
978-953-6894-38-3

Skup
XXI. Hrvatski skup kemičara i kemijskih inženjera

Mjesto i datum
Trogir, Hrvatska, 19.04.2009. - 22.04.2009

Vrsta sudjelovanja
Poster

Vrsta recenzije
Domaća recenzija

Ključne riječi
Passive diffusion; skin absorption; polyethelene glycol; Stratum Corneum

Sažetak
Chemicals pass the skin barrier by process of passive diffusion. The diffusion rate of a compound which determines the rate of absorption through the skin can therefore be described by Fick’ s laws of diffusion. Information on absorption rate of a chemical across the Stratum Corneum, the principal barrier of the skin, can be used to characterize the skin barrier function, which can further be useful in diagnostics of skin diseases such as atopic dermatitis (AD). The purpose of this study was to elaborate a method for the determination of diffusion rate of polyethylene glycols (PEG) of different molecular weights (150-590 Da) which were used as model penetrants. For that purpose experimental protocol was developed, which included: (1) development of a sensitive analytical method for the determination of PEGs in the Stratum Corneum, (2) development of a mathematical model based on Fick’ s second law of diffusion (Eq. 1) to characterize the penetration parameters and (3) evaluation of the method in a patient control study. The analytical method for the determination of PEGs was based on derivatization with pentafluoropropionic anhydride (PFPA), subsequent gas chromatography-electron capture detection (GC– ECD) and GC-MS. The concentration of PEG oligomers in healthy individuals and AD patients was determined in the layers of the Stratum Corneum obtained by consecutive removal of the Stratum Corneum by adhesive tapes. The amount of PEG oligomers in a subsequent strip was plotted as a function of the relative Stratum Corneum depth. The non-steady state diffusion equation (Eq. 1) was fitted to the data enabling determination of diffusion rate and partitioning coefficient. The developed method showed to be suitable to detect differences in skin barrier function between diseased and normal skin. The diffusion through AD skin was twice as high as through normal skin, decreasing with increasing MW of the PEG. The observed enhanced diffusion and lower partitioning tended to be more pronounced in patients with active AD compared to those with inactive AD. This indicates that the state of the disease influences permeability of the skin.

Izvorni jezik
Engleski

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