How do you design and model the complex geometries and architectures for extrusion-based bioprinting?

1 Choose a software

The first step is to choose a software that allows you to design and model your desired geometry and architecture for bioprinting. There are various options available, depending on your level of expertise, budget, and preferences. Some examples are Autodesk Fusion 360, SolidWorks, Blender, or OpenSCAD. These software tools enable you to create 3D models of your bioink structures, using different methods such as sketching, sculpting, parametric modeling, or coding. You can also import or export files from other sources, such as medical imaging data, CAD files, or STL files.

2 Define your parameters

Define your parameters for bioprinting, such as the size, shape, resolution, and orientation of your structures. These parameters will affect the mechanical and biological properties of your bioink, as well as the printing process and the post-processing steps. For example, you need to consider the nozzle diameter, the layer height, the printing speed, the crosslinking method, and the curing time of your bioink. You also need to account for the shrinkage, swelling, or deformation of your bioink during and after printing. You can use software tools to simulate and optimize these parameters, such as COMSOL Multiphysics, ANSYS, or MATLAB.

3 Design your geometry

Design your geometry for bioprinting, using the software tools and the parameters you have chosen. You can create simple or complex shapes, such as spheres, cylinders, cubes, or tori, or you can combine them to form more elaborate structures, such as honeycombs, lattices, or branching networks. You can also use Boolean operations, such as union, intersection, or difference, to modify or merge your shapes. You can also apply transformations, such as scaling, rotating, or translating, to adjust your geometry to your needs.

4 Model your architecture

Model your architecture for bioprinting, using the software tools and the geometry you have designed. You can create different layers, patterns, or orientations for your structures, depending on your desired function and outcome. For example, you can create concentric, spiral, or zigzag patterns for vascular networks, or you can create orthogonal, diagonal, or random orientations for bone scaffolds. You can also vary the density, porosity, or stiffness of your structures, by changing the spacing, width, or height of your bioink strands. You can also incorporate different types of bioinks, such as cell-laden or cell-free bioinks, to create heterogeneous or gradient structures.

5 Export your file

Export your file for bioprinting, using the software tools and the format that are compatible with your bioprinter. You need to convert your 3D model into a 2D slice file that contains the instructions for the extrusion nozzle movements and parameters. The most common file format for bioprinting is G-code, which is a numerical control language that specifies the coordinates, speed, and direction of the nozzle. You can use software tools to generate and edit G-code files, such as Slic3r, Cura, or Repetier. You can also preview and test your G-code file before printing, using software tools such as Pronterface or OctoPrint.

6 Print your structure

Print your structure for bioprinting, using your bioprinter and your file. You need to prepare your bioprinter by calibrating the nozzle, loading the bioink, setting the temperature and pressure, and aligning the printing platform. You also need to prepare your file by transferring it to your bioprinter, either via USB, SD card, or network connection. Then, you can start the printing process by following the instructions on your bioprinter's interface or software. You can monitor the printing progress and adjust the parameters if needed. After printing, you need to perform post-processing steps, such as crosslinking, curing, washing, or culturing your structure.

7 Here’s what else to consider

This is a space to share examples, stories, or insights that don’t fit into any of the previous sections. What else would you like to add?