Researchers led by Daniel Aili at Linköping University in Sweden developed a ‘bio-ink’ to print the tissue-mimicking material on 3D printers.
“Bioprinting is a new and exciting technology to manufacture three-dimensional tissue-mimicking cell cultures. It has been a major problem to develop the bio-ink required ie. a material that can encapsulate the cells and be used in printers. Our bio-ink has several exciting properties that open new opportunities to approach our vision – creating tissue and organs in the laboratory,” said bioengineer Aili.
The properties of the ink can be modified as required. The team reportedly achieved ‘excellent’ results in tests using the material with different cell types: liver cells, heart cells, nerve cells and fibroblasts, a type of cell found in connective tissue. The printed cells reportedly “survived and thrived” despite the harsh treatment involved in the printing process.
The ink contains hyaluronan and synthetic molecules similar to proteins, known as peptides. These are bound together in a hydrogel that functions as a scaffolding for the cells.
“We can use some advanced chemical techniques to control how rapidly the hydrogel forms, in other words the transition from liquid to a gel, that gently encapsulates the cells,” said Aili.
The scientists developed a modular system in which different components can be combined to create different types of hydrogel. The hydrogels provide mechanical support to the cells and encapsulate them without damaging them. They can also control cell growth and behaviour.
The peptides make it possible to control the cells and incorporate different functionalities. An enzyme could be attached to stimulate the growth of bone, for example.
“We are one of the first research groups that can change the material properties both before and after it is printed. We can, for example, increase the degree of cross-linking during the process to provide more stability to the material, and we can change the biochemical properties.
“We can also adapt the material to different types of cells. This is a further step on the way to mimicking the support structures that surround most human cells, the extracellular matrix,” said Aili.
The team refers to its material as ‘4D-printed biomaterial’ thanks to its dynamic and tailored properties.
“Our work is quite basic research, but we are aware that there is a huge medical need for tissue, and for better and biologically relevant models for drug development, not least as a replacement for animal experiments. Progress is rapid in this field at the moment,” said Aili.
The research was published in Biofabrication.
Want the best engineering stories delivered straight to your inbox? The Professional Engineering newsletter gives you vital updates on the most cutting-edge engineering and exciting new job opportunities. To sign up, click here.
Content published by Professional Engineering does not necessarily represent the views of the Institution of Mechanical Engineers.