SHAPE FIDELITY OF GELATIN SCAFFOLDS OBTAINED BY CRYO-3D PRINTING

Kód výsledku v IS VaVaI

<a href="https://www.isvavai.cz/riv?ss=detail&h=RIV%2F00027006%3A_____%2F23%3A10176644" target="_blank" >RIV/00027006:_____/23:10176644 - isvavai.cz</a>

Výsledek na webu

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DOI - Digital Object Identifier

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Jazyk výsledku

angličtina

Název v původním jazyce

SHAPE FIDELITY OF GELATIN SCAFFOLDS OBTAINED BY CRYO-3D PRINTING

Popis výsledku v původním jazyce

Introduction. Scaffolds based on natural biopolymers are widely used in regenerative medicine, tissue engineering, biotechnology, pharmacology and food industry. One of the new methods for fabrication ofscaffolds based on biopolymers is 3D bioprinting. Natural polymers used to scaffolds&apos; production include materials such as gelatin, collagen, fibrin, sodium alginate, and many other polymers of natural origin. The advantage of these materials is high biocompatibility. The main disadvantages of gelatin-based bioinks are the low print resolution and the need to fix the ink during the printing process. To eliminate the above disadvantages, the cryobioprinting can be used, in which, due to the cooling of the bioink during the printing process, it is possible to increase the resolution and increase the shape fidelity of the printed sample.The purpose of this study was to evaluate the shape fidelity of gelatin scaffolds obtained by CRYO-3D printing.Materials and methods. The scaffolds were printed with &quot;Coolness&quot; 3D printer (IPC&amp;C, Ukraine) equipped with a piston-driven system for bioink extrusion and water cooling system with temperature maintenancefor printing table. A blunt needle with an inner diameter of 0.53 +- 0.01 mm was used as an extruder. Using the free software &quot;FreeCAD&quot;, 3D models of a rectangular meander-like patternwere created with the same distance between the filaments, the width, length and height of which were 20.4, 25 and 0.45 mm, respectively. The created models were then prepared for printing using free slicing software &quot;Cura 3.2.1&quot;. In the process of preparing models for printing, the following printing parameters were set: extrusion rate (0.8 mm / s), layer height (0.45 mm), printing speed (0.8 mm / s), and temperature of the printing table (5+-0.5 o C). The scaffolds were printed using 6.5% gelatin solution (180 bloom) as a bioink. The protocol described by Schwab et al. (2020) was used to evaluate the shape fidelity and characterization of the 3D scaffold filaments. Results and discussion. The average printing time of gelatin scaffolds with thegiven parameters, namely the height of the printed layer 0.45 mm, the ink flow rate 0.8 mm/s, and the speed of the extruder 0.8 mm/s, was 205+-0.5 s. Visual analysis of the resulting scaffolds revealed rounding of the outer and inner corners thatwas also observed in 3D printing with gelatin-based composite bioinks. The results of quantitative tests to assess the shape fidelity of the gelatin scaffolds are shown in Table 1. In the first test, we evaluated the printing irregularity in three directions X, Y, Z, which characterized the difference in overall dimensions of the printed scaffold and its 3D model. The largest deviation of this parameter was observed in the direction of printing Z, and was 480.66+-24.51%, thatwas 4.8 times higher than the ideal value of this parameter. The filament diameter was evaluated to estimate the uniformity of the filament in the two printing directions X and Y (test-2), and to compare with the ideal filament diameter (test-3). The filaments of the printed scaffoldswere non-uniform in the two printing directions. The largest deviation from the value of the givenfilaments diameter in the 3D model was observed in the Y printing direction. At the same time, the ratio of the actual filaments diameter to the calculated one was 279.58 +- 14.54% thatwas 2.7 times higher than the ideal value of this parameter. Pore geometry analysis was evaluated in test-4, calculating the pore printability index Pr that was 0.81 +- 0.03, which differs from ideal, and indicated a non-ideal geometry of the printed pores of the scaffold. This was most likely caused by the rounding of the inner corners of the pore.

Název v anglickém jazyce

SHAPE FIDELITY OF GELATIN SCAFFOLDS OBTAINED BY CRYO-3D PRINTING

Popis výsledku anglicky

Introduction. Scaffolds based on natural biopolymers are widely used in regenerative medicine, tissue engineering, biotechnology, pharmacology and food industry. One of the new methods for fabrication ofscaffolds based on biopolymers is 3D bioprinting. Natural polymers used to scaffolds&apos; production include materials such as gelatin, collagen, fibrin, sodium alginate, and many other polymers of natural origin. The advantage of these materials is high biocompatibility. The main disadvantages of gelatin-based bioinks are the low print resolution and the need to fix the ink during the printing process. To eliminate the above disadvantages, the cryobioprinting can be used, in which, due to the cooling of the bioink during the printing process, it is possible to increase the resolution and increase the shape fidelity of the printed sample.The purpose of this study was to evaluate the shape fidelity of gelatin scaffolds obtained by CRYO-3D printing.Materials and methods. The scaffolds were printed with &quot;Coolness&quot; 3D printer (IPC&amp;C, Ukraine) equipped with a piston-driven system for bioink extrusion and water cooling system with temperature maintenancefor printing table. A blunt needle with an inner diameter of 0.53 +- 0.01 mm was used as an extruder. Using the free software &quot;FreeCAD&quot;, 3D models of a rectangular meander-like patternwere created with the same distance between the filaments, the width, length and height of which were 20.4, 25 and 0.45 mm, respectively. The created models were then prepared for printing using free slicing software &quot;Cura 3.2.1&quot;. In the process of preparing models for printing, the following printing parameters were set: extrusion rate (0.8 mm / s), layer height (0.45 mm), printing speed (0.8 mm / s), and temperature of the printing table (5+-0.5 o C). The scaffolds were printed using 6.5% gelatin solution (180 bloom) as a bioink. The protocol described by Schwab et al. (2020) was used to evaluate the shape fidelity and characterization of the 3D scaffold filaments. Results and discussion. The average printing time of gelatin scaffolds with thegiven parameters, namely the height of the printed layer 0.45 mm, the ink flow rate 0.8 mm/s, and the speed of the extruder 0.8 mm/s, was 205+-0.5 s. Visual analysis of the resulting scaffolds revealed rounding of the outer and inner corners thatwas also observed in 3D printing with gelatin-based composite bioinks. The results of quantitative tests to assess the shape fidelity of the gelatin scaffolds are shown in Table 1. In the first test, we evaluated the printing irregularity in three directions X, Y, Z, which characterized the difference in overall dimensions of the printed scaffold and its 3D model. The largest deviation of this parameter was observed in the direction of printing Z, and was 480.66+-24.51%, thatwas 4.8 times higher than the ideal value of this parameter. The filament diameter was evaluated to estimate the uniformity of the filament in the two printing directions X and Y (test-2), and to compare with the ideal filament diameter (test-3). The filaments of the printed scaffoldswere non-uniform in the two printing directions. The largest deviation from the value of the givenfilaments diameter in the 3D model was observed in the Y printing direction. At the same time, the ratio of the actual filaments diameter to the calculated one was 279.58 +- 14.54% thatwas 2.7 times higher than the ideal value of this parameter. Pore geometry analysis was evaluated in test-4, calculating the pore printability index Pr that was 0.81 +- 0.03, which differs from ideal, and indicated a non-ideal geometry of the printed pores of the scaffold. This was most likely caused by the rounding of the inner corners of the pore.

Druh

O - Ostatní výsledky

CEP obor

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OECD FORD obor

40106 - Agronomy, plant breeding and plant protection; (Agricultural biotechnology to be 4.4)

Projekt

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Návaznosti

R - Projekt Ramcoveho programu EK

Rok uplatnění

2023

Kód důvěrnosti údajů

S - Úplné a pravdivé údaje o projektu nepodléhají ochraně podle zvláštních právních předpisů