Vejnoviċ, Ivana. Systematic investigation of different formulations for drug delivery through the human nail plate "in vitro". 2010, PhD Thesis, University of Basel, Faculty of Science.
Official URL: http://edoc.unibas.ch/diss/DissB_9217
Transport experiments were carried out in Franz diffusion cells across human cadaver nail samples at 32°C under an occlusive effect. Caffeine was applied in a concentration of 2% (w/v) from the water and 20% (v/v) ethanol/water solutions and it was detected by UV spectrophotometer. Duration of permeability studies with caffeine was six days. Terbinafine was applied in a concentration of 10% (w/v) from the 60% (v/v) ethanol/water solutions and it was detected by HPLC. Permeability experiments with terbinafine lasted 10 days. Characterization of the nail samples and applied formulations was maintained throughout the study in order to illuminate examined absorption processes. To detect amount of a drug remained in the nail after experiment, milling test has been performed.
Identified potential enhancers for drug delivery through the human nail plate were methanol, dimethyl sulfoxide (DMSO), and hydrophobins. Methanol and DMSO induced irreversible structural changes in nail samples, while hydrophobins in most of the cases formed a film layer on the nail surface acting not only as enhancers but as protectors, too. Addition of 20% (v/v) ethanol in the formulations did not influence negatively the hydration of the nail and therefore the permeability coefficient. Among three different tested hydrophobins in the formulations with terbinafine, hydrophobin B increased permeation rate 13.05-fold, which assorted it in the list of substances able to augment drug delivery through the nail plate. Although a hydrophilic drug with lower molecular weight compared to terbinafine, caffeine reservoir in the nail plate samples was detected to be lower than terbinafine reservoir, which was influenced by the duration of experiment and which supported a theory that terbinafine has an affinity towards keratin in the nail plate. The question: Can we increase permeation rate even more and enable substances with different chemical and physical properties to permeate through the death keratinized cells of the nail plate, requires further investigations. Finally, an amount of drug which would be detected in the blood should be estimated in vivo.
|Advisors:||Hamburger, Matthias Otto|
|Committee Members:||Betz, Gabriele and Sakr, Adel|
|Faculties and Departments:||05 Faculty of Science > Departement Pharmazeutische Wissenschaften > Pharmazie > Pharmazeutische Biologie (Hamburger)|
|Bibsysno:||Link to catalogue|
|Number of Pages:||123 S.|
|Last Modified:||30 Jun 2016 10:41|
|Deposited On:||21 Jan 2011 11:23|
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