AccScience Publishing / IJB / Online First / DOI: 10.36922/ijb.6239
RESEARCH ARTICLE

Painting bio: A vector-based method for precise G-code generation across scales in biofabrication

Zan Lamberger1 Camilla Mussoni1 Nathaly Chicaiza Cabezas1 Florian Heck1 Sarah Zwingelberg2 Sven Heilig1 Taufiq Ahmad1 Jürgen Groll1 Gregor Lang1*
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1 Department for Functional Materials in Medicine and Dentistry, University Hospital of Würzburg, Würzburg, Germany
2 Laboratory for Experimental Ophthalmology I, Department of Ophthalmology, University Hospital Düsseldorf, Düsseldorf, Germany
Received: 18 November 2024 | Accepted: 12 December 2024 | Published online: 12 December 2024
© 2024 by the Author(s). This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution 4.0 International License ( https://creativecommons.org/licenses/by/4.0/ )
Abstract

This study introduces a standardized approach to generating and assembling G-code for biofabrication, ensuring compatibility and convergence across diverse machines and scales. By using vector-based drawing software, such as Adobe Illustrator, shapes are designed as paths and converted into modular G-code blocks (subroutines). This vector-based approach allows for the straightforward design of complex structures, such as organic shapes, by simply drawing them to scale, avoiding the need for labor-intensive construction. These blocks are assembled into a final script with a modified version of Notepad++ that enhances code segmentation and provides real-time visualization. Unlike many commercial slicers, this method offers precise control over the print path—a critical advantage in biofabrication, where anisotropic structures are essential for directed cell growth and orientation-specific mechanical properties needed in biomimetic tissue design. The method’s versatility is demonstrated across techniques from micro-scale applications, such as melt electrowriting, to macro-scale approaches like bioprinting, freeform printing, and in-gel printing. This process streamlines code generation, allowing both simple and complex shapes to be efficiently produced. Although paths are drawn in 2D, stacking layers enables 3D constructs. The method’s standardized, relative G-code format—compatible with most devices—supports easy transfer across machines with clearly marked, machine-specific segments, creating a unified and adaptable codebase for a range of fabrication scales and techniques.  

Graphical abstract
Keywords
Bioprinting
Freeform
Fused deposition modeling
G-code
Melt electrowriting
Funding
This work was supported by the German Research Foundation (DFG, Deutsche Forschungsgemeinschaft) under project number 326998133, as part of the Collaborative Research Center/Transregio 225 (SFB/ TRR 225) “Biofabrication.” The participating subprojects include A07 (PIs: Gregor Lang, Natascha Schäfer, and Dirk Schubert), C06 (PIs: Taufiq Ahmad and Janina Müller- Deile), B04 (PIs: Jürgen Groll and Süleyman Ergün), and B02 (PIs: Jürgen Groll and Iwona Cicha). Additional support was provided by the DFG Priority Programme SPP 2416, CodeChi, project number 525934737 (PIs: Sarah Zwingelberg and Gregor Lang). They also thank the Graduate School of Life Sciences (GSLS) at the University of Würzburg for supporting their Ph.D. students.
Conflict of interest
The authors declare they have no competing interests.
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International Journal of Bioprinting, Electronic ISSN: 2424-8002 Print ISSN: 2424-7723, Published by AccScience Publishing