Optimizing a 3D Bioprinter for FRESH Bioprinting

Duncan McGee*, Vignesh Sivashankar*, Ryan O’Connell, Oxana Tseytlin, Andrey Bobko, and Mark Tseytlin

Department of Biochemistry and Molecular Biology, West Virginia University, Morgantown, WV 26506

Presentation Category: Health Sciences (Poster Presentation #131)

Student’s Major: Biomedical Engineering

Bioprinting can be used in tissue engineering to replicate human body parts like blood vessels, bones, and other natural tissues. This emerging bioengineering method provides an alternative to the animal-based drug testing approach. Bioprinted human cells, tissues, and organs are becoming valuable models during the research and development of new types of treatments. We adapted a 3D plastic printer to print with bioinks, like alginate, using the freeform reversible embedding of suspended hydrogels (FRESH) bioprinting method. The main goal is to optimize the printer settings, such as the print speed and extrusion rate, using the Ultimaker Cura 3D printing software to increase the bioprint's resolution. FRESH utilizes a gelatin support bath to hold the alginate during the printing process. The gelatin beads are in a calcium chloride solution that facilitates the polymerization of the alginate after printing. The sodium alginate forms a hydrogel through ionic cross-linking in the presence of the divalent cation calcium. After the print finishes, the gelatin support bath is heated up to body temperature to melt the gelatin leaving the finished alginate print. Using FRESH 3D-bioprinting, we successfully printed an alginate tube to model an artery. We will then image the alginate tube using the locally built electron paramagnetic resonance (EPR) imaging system. EPR permits 3D mapping of oxygen and other essential for life molecules. Changes in oxygen distribution across the tube will be imaged. As a result, we will determine the oxygen diffusion rate from inside of the tube to outside in this proof-of-concept experiment.

Funding: National Institute of Health

Program/mechanism supporting research/creative efforts: WVU's Research Apprenticeship Program (RAP) & accompanying HONR 297-level course