Figure 3.

The structure and operation of available bioprinting methods: A) Inkjet printing method: In this method, air pressure pulses or mechanical pulses are used to eject the hydrogels/droplets. B) Microextrusion printing method: It uses the pneumatic, piston- and screw-based mechanisms to supply a continuous flow of bio-inks. C) Laser-guided direct cell printing method: This method influences the difference in refractive indices of cells, culture media to trap and assist them onto a receiving substrate. D) Laser-induced direct cell printing method: The vapor bubble is created by the laser and results in the removal of the hydrogel droplets from the absorbing layer.