2024 AIChE Annual Meeting
Optimization of Bioprinting Protocols for Longitudinal Oxygen Imaging
Bioprinting is a method of constructing biological tissue and organs from bioinks, which are formed from hydrogels containing human cells, nutrients, and other important biomolecules for cell health. Several printing technologies have been developed with the extrusion type being most common. An extrusion bioprinter was built in our laboratory that uses a standard 3 mL syringe and a computer-controlled xyz stage. Three main protocols were followed. The first protocol consisted of using an alginate based bioink into a support bath using the Freeform Reversible Embedding of Suspended Hydrogels (FRESH) method. The second protocol added fibrinogen to the bioink and thrombin to the FRESH. The third protocol used a bioink with alginate, calcium chloride, and collagen without the use of a support bath, but was instead printed into very thin layers that were later stacked after crosslinking. After testing, it was concluded that the best protocol used the alginate and collagen. After this protocol has been optimized, live cells and oxygen probes will be introduced in bioinks. Bioprinted cell-laden constructs will be imaged using a locally built electron paramagnetic resonance (EPR) imaging instrument. 4D images (3D space and time) will be analyzed to extract oxygen consumption rates by the cells. A bioprinting/imaging protocol will be developed and refined using obtained experimental results with the ultimate future goal to ensure better success with tissue and organ implantation.