A new solution for in situ monitoring of shape fidelity in extrusion-based bioprinting via thermal imaging

Bioprinting is an interdisciplinary study field, where additive manufacturing is combined with tissue engineering and material sciences. The ever-increasing need for personalized medicine fueled interest in the possibility of using this technique to reproduce biological tissues, allowing bioprinting to establish itself as one of the most promising approach in biomedical research. Producing bioconstructs that resemble living tissues is a very complex and multi-step procedure. Given the complexity of the processes involved, the literature still lacks robust solutions for monitoring the bioprinted construct quality, especially in situ and in-line. Here, a novel non-destructive approach for monitoring the geometries of bioprinted constructs based on infrared (IR) imaging is proposed. Besides the intuitive use of IR information to gain insight on the temperature signature, we propose IR video imaging as a viable solution to overcome traditional problems of visible-range imaging for geometry reconstruction with transparent bioinks, especially when precise information on the last printed layer only is required. The results obtained show a significant new direction for in-line monitoring of bioprinting processes.