3D Printing Methods of Biological Materials used in Tissue Engineering

Fibrin is the basic physiological biopolymer responsible for hemostasis and because of its biodegradability properties is now widely used in tissue engineering for the formation of biological structures called scaffolds. New tissue with desired shape and properties arises by an implementation of suitable stem cells and control of their growth within the scaffold. Fibrin can be obtained in the laboratory by mixing two commercially available biological proteins components, fibrinogen and thrombin. It is assumed, that in the near future this principle will be used in many fields of medicine where replacement or restoration of any type of tissue is required. Current global research in this area seeks to develop the principle of formation of these structures using 3D printing, especially based on inkjet printing technology. This article describes experiments that were performed to clarify, whether micro-droplet dispenser Ultimus 2400 can be used for the production of fibrin structures. The first part gives technical information about a special micro-positioning apparatus, which was designed to grab dispensing nozzles. Further are provided results of experiments that were conducted to determine the behavior and properties of individual injected doses in relation to time, pressure, angle and distance of injection. Mixing properties of fibrin components and ability of deposition one drop on another were also examined to create demanded shapes of structure. All results should be the basis for further development of automated production of fibrin structures using mentioned dispersion technology.