Volumetric printing: increasing the clinical relevance of biofabrication
The hopes for biofabrication applications in the future are high: drug-testing models are being developed, and eventually biofabricated organs may even reduce donor shortages. However, to make such applications possible, technical advancements are necessary. Paulina Nunez Bernal spent her PhD developing a new printing technique and defended her work on February 6.
A new approach to bioprinting
‘Traditional’ layer-by-layer bioprinting is a rather slow process that, in some techniques, can put unnecessary stress on cells. A new approach can improve these aspects, Paulina explains: 'During my PhD I focused on the possibilities of a new technique called volumetric bioprinting, which uses light to create a solid object in a single step. To create the object we direct a series of light projections that end up looking somewhat like a hologram in the middle of our printing vial. We use a material that solidifies in reaction to a certain amount of light, but stays liquid in the absence of light.'
From brand-new concept to promising technology
Paulina’s PhD took some unexpected turns: 'My project was supposed to be on a completely different topic, but just as I was about to start my PhD, my daily supervisor Riccardo Levato came across this volumetric printing concept. It wasn’t published yet, it was just a preprint, but we thought it was interesting and wanted to see whether it was useful for biomedical applications. So we tried adding cells to the process and after just a few months we came out with the first paper.'
'It quickly became clear that this was quite the change in how 3D-printing works.' Paulina explains, 'With volumetric printing we can include bigger cellular structures like organoids in our prints, and the technique is not only faster, but also safer for our cells. Unlike with other printing techniques, we do not push the cells out of a nozzle, which, due to the shear forces, can impair their survival and functionality.'
Using the new technique, Paulina and her team also showed the importance of the print’s structure: 'The printed shapes can change how the cells behave in an in vitro setting. That means you have an extra degree of control over your prints just by choosing different architectures. Getting to increase the biological complexity of the models we were printing was my favourite part of the research.'
The road to clinical applications
Advancements within the field of volumetric printing are happening quickly, but clinical applications are not yet within reach. Paulina explains: 'We are missing information on what actually happens in a native organ and how that compares to our printed structure. The prints look like the organ and they seem to function that way too, but if we add a drug to it, will it behave like the actual organ?'
Right now, the research mostly focuses on the technical developments before such advanced tests can be applied. 'We are still focusing on the printing technique, the materials and the cells. We currently have quite a small material library. Many materials still have to be explored in terms of biological properties, toxicology and safety, before they can be used,' Paulina explains, adding a hopeful note for the future: 'The developments are happening very quickly, so I think the potential is there. Hopefully we can work towards using the prints as a drug-testing platform, or eventually as an implant.'
The next step
After her PhD, Paulina is staying at the RMCU for a postdoc position in the same group. “There are still things I want to explore and I really enjoy working on this type of research and with this team. It’s such a unique interdisciplinary group.” Paulina is also excited to continue coordinating the Biofabrication Master’s programme: “That has been a huge plus for me, teaching and learning from all the students that we come across. That way I don’t just get to advance the research myself, but educate a new generation of researchers as well.”
This article was written by Ellis Mittring.