Automated Image Analysis Methodologies To Compute Bioink Printability

The lack of suitable bioinks in bioprinting is a major limitation in tissue engineering and regenerative medicine. The reasons are multifaceted but can primarily be attributed to the contradictory requirements for bioinks to demonstrate desirable bioactivity while exhibiting high printability. Herein, methods are proposed and tools are provided to automatically quantitate the performance of bioinks using image analysis methods and differential geometry. Several artifact structures are used including a crosshatch to evaluate filament fusion, five-layer tube to evaluate stacked arc accuracy, overhang to test filament collapse, and a novel four-angled pattern to evaluate turn accuracy. Automatic measurements are 95.8% accurate in delineating pores of a crosshatch pattern, 96.5%, 86.0%, 80.3%, and 80.5% accuracy for each angle of a four-angled pattern, 98.9% and 97.9% accuracy for the external and internal radii of a five-layer tube, and 90.6% and 99.0% accuracy for the height and width of a five-layer tube. This automation reduces the time and effort required to analyze a structure and also provides a standardized set of tools to compare different bioinks.