Posted by Hildegard Suntinger 

Cotton cultivation is harmful to the environment and yet consumers do not want to do without it, explains chemist Filipe Natalio of the Weizmann Institute of Science in Rehovot, Israel. That’s why he didn’t grow a substitute, but a truly sustainable cotton – and gave it intelligent properties that can otherwise only be achieved by chemical treatment. Natalio’s cotton fibers are water-repellent, fluorescent and supermagnetic. The researcher in an interview:

How did you come up with the idea of growing cotton with intelligent properties?

When I was in Germany, I did research in the Priority Program Biomimetics, a field of research in which people want to use the mechanisms of nature to develop artificial structures. For example, the natural structure of a bone can give us a new perspective on the construction of houses.

Nature can build certain types of materials much better than we humans can. This can be seen, for example, in photosynthesis, which is a very complex process: It takes light, water and carbon dioxide to produce sugar – and then this sugar becomes sugar cane. In the chemical synthesis of sucrose, twelve steps are required to achieve this. Nature does it in two steps. I saw this as a challenge and wondered why we cannot use these biological mechanisms for cotton as well.

You conduct research at the Weizmann Institute in Tel Aviv in the Department of Plant and Environmental Research. The Kimmel Center for Archaeological Studies is affiliated to it. What does this mean for your research approach?

My lectures are usually entitled The past in the future of materials (laughs). Materials from the past represent cultures and contain information about human behavior. We want to extract this behavior from materials and develop new methods from machine learning and deep learning.

When we research the materials of the future, we want to create a better world by developing a sustainable alternative to existing products. We are inspired by the mechanisms of nature and use methods from material cultivation and biological production. You can use biology to create completely new materials – and do so in a sustainable way. So it will continue to be about materials and the interaction of people who strive for something useful and simple.

New technologies are often expensive and therefore not everyone has access to them. If there is a sustainable product and a conventional one and both cost five euros, then many will choose the sustainable product. But if the sustainable product costs 500 euros, then there is a financial hurdle that few can overcome. The challenge is to implement new technologies that are both sustainable and affordable.

How can this problem be solved in the case of cotton?

Cotton cultivation consumes a lot of water and pesticides and if no crop rotation is practiced, it also destroys the soil. That is why we have abandoned soil and grow cotton in water. With the hydroponic system we have been able to significantly reduce water consumption compared to conventional cultivation. By growing cotton in a greenhouse, we were not tied to the seasons and were able to grow cotton even in winter. Instead of pesticides, we used ladybugs, which eradicated the plant pests.

This experiment dates back to my time as junior professor at the University of Halle, Germany, and it was the first locally and organically grown cotton in Germany. We had it tested by the Faserinstitut Bremen, Germany and got a very good evaluation. However, because it is grown in a greenhouse, the process is still expensive, especially because of the heating and lighting. But we have shown that it is possible to produce cotton locally – without a CO2 footprint. We are currently working on improving the method to meet the United Nations guidelines for a sustainable future. We want to reduce water consumption even further and could achieve 90 percent compared to conventional cultivation.

Your method enables intelligent properties that were previously only possible through chemical treatment. How can we imagine this?

Before we came to chemical applications, we first had to understand plant biology on a multi-scale level: The roots, the stem, the leaves, the fibers – and how the fibers are formed. This requires basic research. There are many researchers doing small-scale research, but there are only about five on a multi-scale scale worldwide. This is the reason why synthetic biology works almost exclusively with bacteria: We don’t know enough about other systems yet.

Cotton is very complex. While we humans have one genome, cotton has four – four super-long DNA strands. This is due to domestication and makes genetics very complicated. In conventional cotton breeding, two different varieties are simply combined; instead of using the genomes, they are simply crossed. If you want to use the genomes, you first have to understand the individual steps from basic research – and then combine them with chemistry.

Video: How cotton grows in a petri dish: “You put the sugar in the liquid, it is absorbed by the root and then biology does the work by itself.” Filipe Natalio. The yellow are the fluorescent fibers. (c) Science Mag

It’s like a watch. If you want the wheels to turn faster or more slowly, you have to understand the function of each individual wheel. In analogy to our biological system, this includes enzymes, fiber structures and plant physiology – from the molecule to the entire plant. We looked at the DNA of the roots and tried to understand how sugar transport works in plants. Only when we understood plant biology could we move on to synthetic chemistry and consider which molecule and which type of chemistry we could use.

The challenge was to synthesize molecules and then feed them into the hydroponic system. We put the synthesized molecules into water, where they were absorbed by the plant and produced cotton, which is either fluorescent, water repellent or supermagnetic. That was the proof of concept. Now we are working on scaling up and we want to move to industrial implementation.

Now to the applications: We can use water repellent cotton to make raincoats, for example. But what do we do with fluorescent cotton?

We are currently working on patents, so I cannot go into details. One way is to sell cotton directly to consumers and the other is to sell it to companies interested in commercialization. The advantage is that the color introduced into the plant with molecules does not wash out so quickly. This means that clothes can be worn for a long time without looking shabby. As a result, new clothing has to be bought less often and the pressure on the supply chain is reduced. If less cotton has to be grown and dyed, then this is sustainable and also has a positive effect on the environment.

Fluorescent cotton (c) Science Mag

And what do we do with super-magnetic clothing?

This was more or less an exercise, because we wanted to see if we could cultivate other properties of cotton. Supermagnetic properties allow the coding of the fibers. When fibers become information carriers, their origin, for example, can be traced – and that is a big issue.

Thank you for the interview.

This project was developed in scientific cooperation with Michaela Eder from the Max Planck Institute of Colloids and Interfaces, Department of Biomaterials in Potsdam, Germany. It is funded by the Weizmann Institute and the German-Israeli Foundation for Scientific Research and Development (GIF). Researchers who see the topic from a different perspective or a different technical perspective – as well as investors – are welcome.

About Filipe Natalio
Filipe Natalio is Portuguese by birth and studied chemistry at the University of Lisbon, Portugal. He completed his doctorate under Professor Werner Müller and Professor H.C. Schröder at the University of  Medicine, Mainz, Germany in 2010. The hydroponic cultivation of cotton dates back to his time as Junior Professor at the University of Halle, Germany.

Natalio holds two patents, one for antifouling paint for boats and one for a sustainable production method for intelligent textiles.
He is currently researching at the Weizmann Institute in Rehovot at the Institute for Plant and Environmental Research, which is linked to the Kimmel Center for Archaeological Studies. Here he can also pursue his interest in antique materials.

Another focus of his work is the cultivation of materials. He is pursuing a new and alternative production method to produce environmentally friendly materials with special properties. He combines plant biology with intelligent molecular design. This approach is presented in the film Cotton-9, which was awarded second prize at the Nanospots Kurz Film Festival in 2014.