If you are experiencing problems downloading PDF or HTML fulltext, our helpdesk recommend clearing your browser cache and trying again. If you need help in clearing your cache, please click here . Still need help? Email help@ingentaconnect.com

Monitoring 2-Ethylhexyl-4-Methoxycinnamate Photoisomerization on Skin Using Attenuated Total Reflection Fourier Transform Infrared Spectroscopy

$29.00 plus tax (Refund Policy)

Buy Article:


Photoisomerization and photodimerization of a widely used UVB filter, 2-ethylhexy-4-methoxycinnamate (EHMC) on a ZnSe surface and baby mouse (Mus musculus Linn.) skin were monitored using attenuated total reflection Fourier transform infrared spectroscopy (ATR-FT-IR). Differentiation between the E- and the Z-EHMC could be achieved by examining the infrared (IR) peak at 981 cm−1 (b peak), which corresponds to the CH rocking deformation vibration of Ph–CH=CH– detected only in the E configuration. By plotting the ratios of the peak area of the b peak and an internal standard peak (1060–998 cm−1) against mole percentage of Z-isomer in the E-Z mixtures, a linear calibration plot was obtained. Thus, a simple estimation of the mole percentage of each configuration in a sample was obtained. At the same UVB exposure, photostationary equilibrium of the E/Z isomerization on the surface varied with the applied amounts of EHMC. Photoisomerizations on ZnSe and on baby mouse skin were comparable. Less than 10% of E-EHMC changed configuration when the mouse skins applied with 1.0–4.0 mg/cm2 E-EHMC were exposed to sunlight for 60 min (UVB radiant exposure of ∼0.30 J/cm2). This corresponded to less than 5% loss in UV filtering efficiency. However, at a typical EHMC skin coverage (∼0.2 mg/cm2), 0.30 J/cm2 UVB exposure induced ∼50% photoisomerization resulting in 25% loss of UV filtering efficiency. No photodimerization was detected even at the extreme EHMC coverage of 4.0 mg/cm2 after a UVB exposure of 0.90 J/cm2.


Document Type: Research Article

DOI: http://dx.doi.org/10.1366/000370207779947648

Affiliations: Sensor Research Unit, Department of Chemistry, Faculty of Science, Chulalongkorn University, Bangkok, Thailand

Publication date: February 1, 2007

More about this publication?
Related content



Share Content

Access Key

Free Content
Free content
New Content
New content
Open Access Content
Open access content
Subscribed Content
Subscribed content
Free Trial Content
Free trial content
Cookie Policy
Cookie Policy
ingentaconnect website makes use of cookies so as to keep track of data that you have filled in. I am Happy with this Find out more