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Artificial cell membranes are widely prevalent in bio-science, even though a number of their aspects have not been understood properly.

The University of Southern Denmark's team has discovered one of the secrets of these membranes, which is, that they have "beautiful flower formations" inside them.

"To understand complex systems such as real biological cells it is absolutely crucial that we understand the simpler systems that make up the cell, for example, the cell membrane, through studies of model membranes," Jonas Jeppesen said in a press release.

With his team, Jeppesen made up his mind to probe into the structures inside the membranes, so that they could find out whether they are static or got altered during their lifespan.

"We knew that freezing membranes containing two different types of lipids (fat molecules) cause domains of curious flower shapes to form. It is kind of like freezing a 'mixture' of oil and water. When the water freezes at 0 degrees C it forms ice crystals, or domains, in the still liquid oil. We knew these flower shaped domains form, but we did not know if they were stable static structures, or if they would change shape given time," Jeppesen said.

The team took some time-lapse photos. The members showed how fat molecules change after the temperature drops down below the freezing point, after which the molecules assume the shape of flowers. However, the shapes keep changing after every few days, and following a few weeks, they get rounded.

This is the process that is followed by all elements in nature, believe the researchers. They try to acquire a state of equilibrium, which is "round" in these domains.

"Everything in nature is round. Find a square tree trunk or a square oil droplet on your frying pan and you would be suspicious," Jeppesen said. "But it was important to find out how long they remain flower shaped. Researchers have assumed the flower shapes to be static, at least for several hours. We have now shown that it is reasonable to assume the flowers are static for hours, but not for days."

The study was published in the Oct. 26, 2015, issue of Langmuir.

YouTube/syddanskuniversitet