Open AccessMicroscopic FT‐IR/DSC combined system used to investigate the thermotropic behavior of lipid in porcine stratum corneum after pretreatment with skin penetration enhancers
Author(s) -
Lin ShanYang,
Duan KwoJen,
Lin TsungChien
Publication year - 1996
Publication title -
skin research and technology
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.521
H-Index - 69
eISSN - 1600-0846
pISSN - 0909-752X
DOI - 10.1111/j.1600-0846.1996.tb00149.x
Subject(s) - thermotropic crystal , azone , stratum corneum , penetration (warfare) , chemistry , fourier transform infrared spectroscopy , biophysics , analytical chemistry (journal) , phase (matter) , chromatography , organic chemistry , biochemistry , chemical engineering , permeation , medicine , liquid crystalline , pathology , operations research , membrane , engineering , biology
Background: The stratum corneum (SC) is the outermost barrier of the skin to prevent environmental attack and water loss. The function of SC has been found to be related to the lipid phase transitions in SC. In this study, we used a newly developed microscopic Fourier transform infrared spectrometer equipped with a thermal analyzer (FT‐IR/DSC) system to simultaneously investigate the correlation between the thermotropic response and the structural changes of lipids in porcine SC after pretreatment with skin penetration enhancers. Methods: The CH 2 stretching vibrational bands near 2850 and 2920 cm ‐1 of lipid in porcine SC pretreated with skin penetration enhancers were studied by this microscopic FT‐IR/DSC system. Results: The results indicate that the temperature‐induced change in the peak position for both asymmetric and symmetric CH 2 stretching bands was found to be shifted to higher wavenumber position with increased temperature and this alteration was reversible after cooling the heated SC sample, which was independent of the skin penetration enhancers pretreated except the SC sample pretreated with azone/propylene glycol. Conclusion: The porcine SC pretreated with azone/propylene glycol exhibited a marked change in the phase‐transition temperatures of lipid during 1 st and 2nd heating processes, suggesting the synergistic effect of both azone and temperature on the lipid thermotropic behavior of porcine SC.