Since their invention by Theodore H. Maiman in 1960, lasers have driven many advances in manufacturing. New research from Vilnius University in Lithuania combines laser writing and 3D printing to create more efficient micro-structures for the culture of stem cells.
As the undifferentiated (i.e. cells without a specific function) cells of a living organism, stem cells can adapt to the structure of any specialized cell, a process called ‘sorting-out’. Cells sort out based upon environment conditions, such as blood flow or structure. This is evident in the approach to 3D bio-printing taken by Organovo and others.
With computer aided design, biologists can specify structures that will allow cells to grow in a particular way, i.e. to form the pore-structure of the skin, or the cylindrical tissue of a vein. As to be expected, getting the right shape and form is a delicate process. The research from Vilnius University adds laser precision to such 3D microfabrication.
Direct laser writing of a 3D printed structure is possible because of the femtosecond (i.e one quadrillionth of a second) speed the laser works at. The light pulses are concentrated in such a way that it doesn’t completely disintegrate the printing material. Fused filament fabrication and stereolithography 3D prints were tested in the study for the different print speeds, resolution, and materials. In the study, entitled 3D microfabrication of complex structures for biomedical applications via combination of subtractive/additive direct laser writing and 3D printing, the team successfully added details to these printed parts that are finer than the width of a human hair.
3D printing at the nano-resolution could be invaluable to the industry’s growing presence within medicine. Recently, there has been much buzz around the printing of organ-on-a-chip structures that, like the minute vessels found in human kidneys, require microscopic attention to detail. And, with 200 different types of cell structures within the human body, it is perhaps an understatement to say that this research has a lot of potential.
