Laser bioprinting without donor plate

A promising laser bioprinting technology based on the effect of laser-induced direct transfer is rapidly developing and is already actively used in biotechnology and medicine today. Typically, such technologies use donor plates with an absorbent coating, from which gel microdroplets with living cells and microorganisms are transferred to an acceptor substrate under the action of a laser pulse. This article proposes a new bioprinting technology that makes it possible to transfer microdroplet not only without an absorbing coating, but also without the donor plate itself. The essence of this method is that the transfer to the surface of the acceptor is carried out by a series of nanosecond pulse with a wavelength of 3 μm directly from the surface of a liquid with microorganisms. The mechanism of a liquid jet and microdroplets formation upon absorption of a laser pulse in a thin surface liquid layer is discussed in detail. It has been shown that microorganisms transferred using the new bioprinting technology are viable and can be successfully cultivated on a dense nutrient medium.