An example of Nile red fluorescence microscopy staining of human skin, which allows for the screening and evaluation of the skin's lipid content. In red and yellow are different types of lipids, which are molecules that are soluble in organic solvents and often have a fatty acid. Stained blue are cell nuclei. Differences in lipid concentration, distribution and composition can affect the permeability of skin.
A version of this article appeared in the print edition of The Straits Times on September 25, 2015, with the headline Beautiful Science. Subscribe