An open source extrusion bioprinter based on the E3D motion system and tool changer to enable FRESH and multimaterial bioprinting
Adam Engberg1, Christina Stelzl1, Olle Eriksson1, Paul O’Callaghan1 & Johan Kreuger1
1 Department of Medical Cell Biology, Uppsala University, Uppsala, Sweden.
Bioprinting is increasingly used to construct complex 3D cell models and tissue constructs for in vitro studies, and its capacity to produce transplantable tissues is being intensely explored. However, progress in these fields could be further accelerated by increasing the access to easy-to-use open source bioprinters.
Here we describe an open source extrusion bioprinter based on the E3D motion system and tool changer which enables high resolution multimaterial bioprinting.
The E3D motion system and tool changer was adapted to control the position of a custom 3D-printed syringe pump extrusion tool, equipped with a stepper motor to actuate the plunger and regulate bioink extrusion. The bioprinter is housed in a polycarbonate enclosure equipped with a HEPA filter to reduce the risk of contamination during printing. The versatility of the bioprinter was demonstrated by creating collagen constructs using the freeform reversible embedding of suspended hydrogels (FRESH) method (1), as well as printing multimaterial constructs composed of distinct sections of laminin and collagen bioink. Image analysis of cell viability dyes was used to evaluate the capacity of the bioprinted constructs to support survival of breast cancer cells following direct seeding onto printed constructs or after printing in cell-laden bioinks, and was assessed after short-term (24 h) and long-term (1 wk) incubations (2).
The syringe pump extrusion tool is compatible with different syringe volumes, and needles and nozzles of different calibres, and we determined that narrow linear features could be accurately reproduced (100 ± 12 mm) when extruding bioinks through a 50 mm needle. The dimensions of FRESH and multi-material printed constructs proved faithful to their intended designs, and a high degree of cell viability was seen for cells seeded onto collagen or dispersed in laminin bioinks following both short- and long-term incubations. Furthermore, cell death could effectively be studied in cells grown on FRESH printed collagen constructs following exposure a known apoptosis-inducing agent.
This open source bioprinter is easily adapted to the specific needs of various bioprinting applications; for example, creating small-scale 3D tumor tissue constructs for the purpose of drug-screening. The bioprinter solution presented here is versatile, easy-to-use, and the motion system is already supported by open source data, which together offer an accessible entry point to the novel and rapidly expanding field of bioprinting.
1 Lee A, Hudson AR, Shiwarski DJ, et al. Science 365(6452):482-487 (2019)
2 Engberg, A., Stelzl, C., Eriksson, O. et al. Sci Rep 11, 21547 (2021).