Tijmen Booij is a Dutch biomedical doctor and scientist whose workplace is where cells grow in wood – Finnish birch trees, to be precise.
Booij leads a research group on automation at ETH Zurich’s technology platform NEXUS Personalized Health Technologies, which provides technology services and tools for medical researchers. In his laboratory, large robots pipette drugs onto plates where hundreds of cell clusters are embedded in a gel-like substance and grow side by side. The cells are derived from tumours of cancer patients, and the robots are used to test how different drugs work on them.
A cancer drug proven to work in the laboratory can save lives, but it takes hard work to screen new drug molecules. Booij's team's mission is to find ways to make drug research more efficient through technology. Automation robots are one answer to this need.
"Cell samples isolated from humans are a very important and valuable material for medical research, but they are difficult to obtain. It is therefore important to be able to carry out experiments on a miniature scale – we are talking about microlitres. This allows us to do more science with fewer resources," says Booij.
What does birch have to do with all this? The hydrogel in which the precious cells grow is made of only wood and water. In cell culture, cells isolated from tumours cannot survive long outside the human body without right growth conditions. The hydrogel, together with specific growth medium, supports the cells when grown outside the human body and provides them a suitable three-dimensional environment to grow and multiply. Without supportive growth conditions, no cell-based research could be done. The hydrogel, together with specific growth medium, supports the cells when grown outside the human body and provides them the right conditions to grow and multiply. Without supportive growth conditions, no cell-based research could be done.
The most valuable thing you can make from pulp
You cannot make cell culture hydrogels from just any wood fibers. Its secret is nanocellulose, which is pure cellulose processed to the highest degree. Nanocellulose is essentially the same material as ordinary pulp used to make paper, but, as its name suggests, it is processed down to a much smaller size.
"When wood cellulose fibers are broken down to the nanoscale, millimetre parts per million, its properties change radically," says Tony Kiuru, Senior Manager, Business Development at UPM Biomedicals, a cell culture hydrogel manufacturer.
Thanks to its exceptional properties, nanocellulose has the potential to address painful environmental issues in many challenging industry sectors. It is stronger by weight than any steel grade, and its absorbency and thermal insulation properties outperform many traditional materials used in industry. In recent years, researchers have predicted that nanocellulose could be used in applications such as a raw material for wood-based electronics and as a biodegradable packaging material.