The most widely used bioprinters are extrusion, inkjet and laser-based printers. Each type involves slightly different physics and has its own advantages and disadvantages. An extrusion printer loads a material, known as bioink, into a syringe and prints it by forcing the ink out with a piston or air pressure.
The bioink may be a collection of pure living cells, a suspension of cells in a hydrogel or a polymer. Inkjet bioprinters function in a similar way but use either a piezoelectric crystal or a heater to create droplets from a small opening. Laser printers focus a laser beam on a ribbon, where a thin layer of bioink is spread, and results in high cell viability.
Biological products created by bioprinting are generally not immediately useable. The printer may create an initial configuration of cells, which multiply and reassemble into a new configuration in a process similar to that of an embryo’s development.
The Physics of bioprinting is available in the journal, Applied Physics Reviews (DOI: 10.1063/1.5087206)
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