Xolography: light-based 3D printing for biomedical applications

A team from Eindhoven University of Technology (TU/e) has further developed xolography technology for the production of living cell structures using 3D printing. The process, which is based on light projection, enables the production of high-resolution biological structures and could be used to produce tissue or organ models in the future. The results of the study were published in the journal Advanced Materials.

Xolography is an additive manufacturing process that uses visible and UV light to convert light-reactive fluids into solid structures. Two light beams with different wavelengths are specifically projected onto the fluid, resulting in highly detailed 3D objects. Using this method, the researchers at TU/e were able to create microstructures with a resolution of up to 20 micrometers, which is roughly the size of a human cell.

Lena Stoecker, a PhD student in the Biomaterial Engineering and Biofabrication group, has adapted the process specifically for printing cell materials. She explains that the precision of the method enables the development of physiologically realistic cell environments. Such structures could be used in future for research into diseases or the development of new therapies. Professor Miguel Dias Castilho, who is leading the project, emphasizes that the process is still at an early stage, but offers potential for the bioprinting sector.

In addition to high-resolution production, Xolography allows the mechanical properties of the printed material to be controlled in a targeted manner. By adjusting the light intensity, different degrees of material hardness can be achieved within a structure. This enables, for example, the production of hydrogels that mimic certain tissue environments and can be used in cell culture.

In addition, the team was able to print temperature-responsive hydrogels that deform over time and could therefore potentially be used for artificial muscles or other adaptable tissue structures. Dias Castilho explains that these results pave the way for future applications in tissue engineering. The aim is to develop functional tissue models for regenerative medicine and implant technologies in the future.

The researchers are already working on further improving the biocompatibility of the materials used. One challenge is to adapt the photoinitiators so that they are optimally suited for medical applications. In collaboration with industrial partners, research is also being carried out into scaling up the technology for clinical applications.

With its latest findings, the TU/e working group has shown that xolography could be a promising method for the production of complex biological structures. In the long term, the technique could enable the development of personalized implants and tissue replacement materials, but for the time being it remains a research approach that requires further optimization.

Stoecker adds: “I am well aware that our research has to still go a long way to reach the clinic, but I like the idea, that maybe one day, the techniques we develop in the lab will contribute to improve the health and thereby the life of somebody.”