By precisely controlling pressure, temperature, and compression time, the researchers were able to adjust the size of the gaps.
Kniss likened the fiber structure to a scaffold that supports a piece of sculpture. The thermal compression technique, he said, provides a new method to modify the structure of scaffolds that could one day be used to grow human organs in the laboratory.
"The key to making this technology work is finding a cheap and easy way to mass produce the scaffold," Yang said. "And this is the way to do it."
For the second part of this project, the researchers grew placental cells in two fibrous beds, one with an average gap size of 30 micrometers, and another with an average gap size of 40 micrometers. Placental cells, with an average diameter of about 10 micrometers, provide a good test case because they are similar to the cells that make up the body's organs, Kniss said.
When the fibers were an average of 30 micrometers apart, the cells reproduced very quickly and spread throughout the bioreactor.
But when the fibers were 40 micrometers apart, the cells formed clusters in the open spaces, and initiated chemical functions as they would in the body before differentiating.