Development and validation of biochemical markers of the skin barrier function

Đapić, Irena (2014) Development and validation of biochemical markers of the skin barrier function. Doctoral thesis, Faculty of Science > Department of Chemistry.

[img]
Preview
PDF
Language: Croatian

Download (3MB) | Preview

Abstract

Natural moisturizing factors (NMF) play important role in the regulation of pH and hydration of the stratum corneum and the intercellular lipids form a barrier to transport of substances through the skin. The primary aim of this thesis was to develop reliable and selective LC-UV and LC-MS methods for the determination of biomarkers of skin barrier function including free amino acids, free fatty acids and ceramides obtained by tape stripping technique. Sensitive and robust RP-LC-UV method for determination of NMF components, histidine, pyroglutamic acid, trans- and cis-urocanic acid and tyrosine in the stratum corneum and interstitial fluid was developed. Extraction of NMF components with ammonia avoids a time consuming neutralization step as required with extraction procedures using strong base or acid. The method for determination of free fatty acids (FFAs) in the stratum corneum is based on detection of 3-acyloxymethyl-1-methylpyridinium iodide (NMP) derivatives in positive ionization mode using RP-LC-ESIMS and multiple reactions monitoring. To overcome the matrix effect, FFAs in the human stratum corneum were quantified by “surrogate” analyte method and internal standardization using isotope labelled derivatives of FFAs. The content of FFAs originated from the adhesive tape was calculated from the correlation with C12:0 signal not detected in the stratum corneum. Developed LC-UV and LC-ESI-MS methods showed to be reproducible and sensitive enough for simultaneous detection and quantification of NMF or eight long and very long chain FFAs in the normal and compromised human stratum corneum. Ceramide classes were isolated from human epidermis by multiple extraction steps. Synthetic ceramides III, IIIB and VI were characterized by LC-ESI-MS technique.

Item Type: Thesis (Doctoral thesis)
Keywords: biomarkers of the skin barrier function, free fatty acids, LC-ESI-MS, LC-UV, NMF, skin barrier, surrogate analyte
Supervisor: Jakša, Ivone and Kobetić, Renata
Date: 2014
Number of Pages: 166
Subjects: NATURAL SCIENCES > Chemistry
Divisions: Faculty of Science > Department of Chemistry
Depositing User: mag. bibl. Ana Šafran
Date Deposited: 03 Dec 2014 13:39
Last Modified: 15 Jun 2015 12:31
URI: http://digre.pmf.unizg.hr/id/eprint/3442

Actions (login required)

View Item View Item