Rapid Oxidation of Skin Oil by Ozone
2016
Zhou, Shouming | Forbes, Matthew W. | Katrib, Yasmine | Abbatt, Jonathan P. D.
The reaction of gas-phase ozone with human skin oil has been studied at room temperature. Skin oil was exposed to ozone at mixing ratios similar to those in the ambient environment and then analyzed for condensed-phase products using direct analysis in real time mass spectrometry (DART-MS). Prior to ozone exposure, skin oil gives rise to prominent mass spectral signals indicative of highly unsaturated alkenes, sterols, triglycerides, long-chain fatty acids, pyroglutamic acid, and probably waxy esters. Upon oxidation with 50 ppb ozone for 90 min, there is a rapid loss of alkene, fatty acid, and triglyceride signals resulting from efficient multiphase ozonolysis. Oxygenated products, including a variety of carboxylic acids, are identified via studies with pure compounds present in skin oil, i.e., squalene, cholesterol, and triolein. The chemistry is rapid, occurring on time scales of tens of minutes, implying that these highly oxygenated reaction products are always present on human skin both indoors and outdoors.
显示更多 [+] 显示较少 [-]