Even after nine months soaking in the womb, a newborn's skin is smooth unlike an adult's in the bath. While occupying a watery, warm environment, the newborn manages to develop a skin fully equipped to protect it in a cold, dry and bacteria-infected world. A protective cream called Vernix caseosa (VC), which covers the fetus and the newborn, aids in the growth of skin both before and after birth. VC provides 'waterproofing' in utero, allowing skin to grow in wet conditions, while after birth it hydrates and cleanses, even healing when applied to ulcers. Prof. Joke Bouwstra, a specialist in the skin barrier and its synthesis at Leiden University, and her colleague Robert Rimann set out to study VC in detail and has produced a synthetic version of this natural buttery ointment which shows the same structure and unique properties. As well as helping pre-term babies develop essential protection against temperature changes, dehydration and infection, artificial VC could also benefit sufferers of skin disease.
Like most moisturising creams, VC is mostly water. Its outstanding properties come from the addition of just 10% each of lipid molecules and dead skin cells (corneocytes), so the exact composition of the mixture is important.
For the lipids, X-ray diffraction measurements at the Dutch/Flemish DUBBLE beamline at the ESRF (European Synchrotron Radiation Facility) allowed the Leiden researchers to find the proportions of the various forms in the cream, even distinguishing between complex molecules differing in chain length.
The corneocytes were also studied using electron microscopy, yielding their size, shape and water content.
But equally important is how the mixture arranges itself. Lipid molecules are shaped something like lollipops, with a round end that prefers to be surrounded by water and a stick which prefers to make a raft with other lollipop sticks. VC contains several different lengths of lipids, which form d
|Contact: Montserrat Capellas|
European Synchrotron Radiation Facility