P.C. Rossin College of
Engineering and Applied Science
The new shape, first identified by Lehigh professor's team, has now been found in soap bubbles by physicists in Ireland and the UK.

This just in...a scutoid sighting!

Physicists in Ireland and the UK have identified scutoids in a bubbly foam made with dishwashing liquid, reports Physics World.

The work of foam physicists Stefan Hutzler (Trinity College Dublin) and Adil Mughal (Aberystwyth University) follows the July 2018 discovery of the geometric shape in skin cells by researchers from Spain and the United States. That team, which included Lehigh University's Javier Buceta, found that epithelial cells adopt the twisted prism shape, which enables them to minimize energy use and maximize packing stability during tissue bending.

According to Physics World, “the formation of scutoids in a simple foam suggests that physical processes are driving their creation, which could help with the development of artificially-grown tissues and organs.” 

Mughal and Hutzler's research placed evenly sized bubbles, created by driving air from an aquarium pump into a solution made of dishwashing soap, between two concentric cylindrical surfaces, replicating the curved tissues in which biological scutoids were found. The physicists, who also utilized computer simulations, believe that scutoids formed as the bubbles sought to minimize their surface energies, a process long recognized as the prime driver of foam cell formation. 

Buceta, an associate professor of bioengineering at the P.C. Rossin College of Engineering and Applied Science and a faculty member in the chemical and biomolecular engineering department, tells Physics World that his team was very excited about the Trinity-Aberystwyth study: “First, it revealed that our research was getting coverage and captured the interest of other groups working on different problems. Secondly and more importantly, it proved that our idea about why nature decided to pack cells following this geometry was true: an energy minimization principle. In our case, we developed a biophysical model that was in agreement with experiments, but cells are way more complicated than foams and to build our model we discarded some energetic contributions under the assumption that tension was the most relevant one.”

Buceta adds, “As Hutzler and colleagues mention in their paper, this is a rough approximation and other terms can be relevant, but their experiments have shown that tension is indeed enough and that cellular packing can be explained invoking an energy minimization principle. Following these ideas, we are currently investigating more in detail these concepts of energy and forces in tissues and trying to link them with evolutionary principles.”

Read the full story at Physics World.

Scutoids

The scutoid, a previously unknown geometric shape found in skin cells and now bubbles, is described as a twisted prism or a "prism with a zipper." (Credit: University of Seville)

Javier Buceta

Javier Buceta, associate professor of bioengineering and also of chemical and biomolecular engineering Credit: Lehigh University