Femtosecond Laser-Based Bioprinting

Abstract

The paper demonstrates the possibility of laser printing with hyaluronic acid-based hydrogel using femtosecond laser pulses and donor substrate without absorbing metal coating. Optimum parameters of laser exposure were determined to provide stable transfer wherein the initial velocity of microjets lies in the range of 60 to140 m/s. It is shown that when laser radiation is focused into the bulk of glass for the whole range of used laser pulse energies of 10 to 1000 μJ only an insignificant “swelling” of the hydrogel layer occurs without transfer. It is shown that photon impulses should be taken into account when using femtosecond radiation for printing. A needle hydrophone was used to estimate shock and acoustic waves that will affect living microsystems during the laser-based bioprinting process. When a femtosecond laser pulse with an energy of 250–1000 μJ is absorbed, a shock wave is formed, the amplitude of which can reach 10⁴ atm at a distance of ~20 μm from the optical axis. These findings may be useful for the development of laser bioprinting technology and its promising area of laser engineering of microbial systems.