A.A. Kisel – Graduate Student, IATE NRNU MEPhI, Laboratory Assistant Researcher, Laboratory  of Biomaterials and Fabric Constructions A.F A. Tsyb Medical Radiological Research Center –  Branch of the National Medical Research Radiological Center of the Ministry of Health  of the Russian Federation (Moscow)

E.E. Beketov – Ph.D. (Biol.), Head of the Laboratory of Biomaterials  and Fabric Constructions A. Tsyb Medical Radiological Research Center – Branch of the National  Medical Research Radiological Center of the Ministry of Health of the Russian Federation (Moscow)

E.V. Isaeva – Ph.D. (Veter.), Senior Research Scientist, Laboratory of Biomaterials  and Fabric Constructions A. Tsyb Medical Radiological Research Center – Branch of the National  Medical Research Radiological Center of the Ministry of Health of the Russian Federation (Moscow)

P.V. Shegay – Ph.D. (Med.), Head of the Center for Innovative Radiological and Regenerative Technologies, National Medical Research Radiological Center of the Ministry of Health of the Russian Federation (Moscow) L.N. Komarova – Dr.Sc. (Biol.), Professor, Head of the Biology educational program, 

IATE NRNU MEPhI (Moscow)

N.B. Epshtein – Dr.Sc. (Pharm.), Professor, Head of the Pharmaceutical Center for Practical 

Training and Competencies, IATE NRNU MEPhI (Moscow)

N.E. Shubin – Professor, Dr. Sc. (Chem.), Ph.D. (Tech.), Development Director of «System Products for Construction» (Vorsino Industrial Park, Kaluga Region)

Tissue engineering opens a number of possibilities for the treatment of patients with damaged tissues and organs. Extrusionbased 3D-bioprinting is key method for tissue scaffold creation. The development of the approach is related to new, highly functional materials with defined physical and chemical properties, as well as improvement of existing ones. Other issues include are: optimal concentration of the material, method of polymerization, the presence of growth factors and other components of the scaffold, affecting the proliferation and differentiation of cells. Another way of the approach development is related to technical issues of bioprinting process. Similar to conventional 3D-printing the following parameters are of interest: temperature of the material and the printing table, layer height, print speed, and etc. At the moment, there are no described approaches of comprehensive testing of the materials relating to appropriate printing parameters and in general, its suitability for bioprinting in the available scientific literature.

Aim of this work was to verify the approach materials for material testing from the point of view of its applicability for extrusion based 3D-bioprinting.

In the course of the work, an assessment of rheological properties of the material was made. Temperature of “sol-gel” transition was determined. It was determined that the printing modes suitable for the hydrogel using 21G needles are those that include a layer height of at least 50% of the nozzle diameter and with a material yield that is 50% higher than the calculated one. It was found that 12% gelatin reproduces vertical angles in models well up to a value of 45°. Printing was reproduced over the entire speed range (5…20 mm/s with 2.5 mm/s increment), which can significantly reduce the printing time of products that include simple geometry.

The proposed testing approaches could be considered as comprehensive and can be applied in case of a wide range of hydrogels and bioprinters. This work will be relevant for researchers in the field of tissue engineering.

Kisel A.A., Beketov E.E., Isaeva E.V., Shegay P.V., Komarova L.N., Epshtein N.B., Shubin N.E. Methods for selection of extrusion 3D printing parameters by hydrogels. Technologies of living systems. 2020. V. 17. № 3. P. 61–. DOI: 10.18127/j20700997-202003-07 (In Russian).

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