Results
Validation and Characterization
The concept was assessed to test initial printability using a 6 % (w/v)
sodium alginate (dissolved in sterile double distilled water) (see
Appendix 1 for a detailed protocol). Cell-free bioprinting experiments
were performed initially using an 18G syringe needle as the nozzle.
Subsequent analysis on optimal parameters were then carried out. All
materials used were purchased from Sigma-Aldrich Pty. Ltd. (South
Africa), unless otherwise specified.
Proof of concept: does the extrusion mechanism work as intended and is
it capable of printing geometrically complex constructs?
The computer aided design (CAD) software SketchupMake2017 (v.17.2.2555)
was used to design a grid-like structure for initial printability tests.
Dimensions include: Height = 19.80 mm
Width = 19.80 mm, Layer height = 2 layers (0.2 mm). Cura (v.15.04.2) was
used as the slicing software as well as for the parametrization of the
printing process. The printing parameters include Layer height (1 layer
= 0.1 mm), Shell thickness (0.4 mm), No retraction, Bottom/Top thickness
(0.4 mm), Fill density (100%), Print speed (10mm/s), Flow rate (150%),
Nozzle diameter (18G needle).