Interview with Palladium Global Science Award prize winner Professor Makoto Fujita

We spoke to Makoto Fujita, who was named runner up in the Best Scientific Development nomination at the inaugural prize giving ceremony, winning a $60,000 prize. We discussed his seminal work on metal-directed self-assembly, the current role of palladium across a range of industries, and the future of molecular-level innovation.

You were named among the inaugural winners of the Palladium Global Science Award last year for your work on metal-directed self-assembly. Can you explain the basic principles of self-assembly?

Self-assembly is a phenomenon in which constituent components spontaneously assemble to form an ordered structure. It is crucial that the components interact and weakly attract each other. As countless assembly states are tested through trial and error, the most thermodynamically favourable pathway is selected, converging into a unique, definitive structure. We focused on the interaction between palladium ions and organic compounds as the weak interaction that drives this self-assembly. As a result, we discovered that this approach is extremely effective for constructing various nanoscale structures, allowing us to pioneer and expand a new field of academic research.

Let’s take a step back in time. How did you first come into palladium from an academic standpoint?

When I first conceived of metal-directed self-assembly, I experimented with combinations of various metals and organic compounds. Ultimately, however, it was only when using palladium that the self-assembly occurred efficiently and exactly as intended. Since then, palladium has been an outstanding partner in my research.

What are the specific properties of palladium that make it so vital to your research?

The interaction between metals and organic compounds cannot induce self-assembly if it is too strong or too weak. If it is too strong, the components bind immediately upon contact, resulting in a disordered mass. On the other hand, if it is too weak, nothing happens at all. The fact that the interaction between palladium and organic compounds possessed the perfect, moderate binding strength for self-assembly was the major key to our success.

How long have you been working with nanostructures? What advantages do they have when it comes to working with palladium?

I have been working on this for over 35 years, ever since our first report in 1990. By utilizing self-assembly, we can easily create huge, complex structures that would be virtually impossible to achieve through conventional chemical synthesis. At the time, the question of how to construct nanoscale materials was one of the major challenges in the field of chemistry, and metal-directed self-assembly clearly provided a definitive answer to that question.

Your method is set to enable the creation of entirely new materials – what kinds of materials are you hoping to develop yourself and work alongside others to create?

What excites me most are ‘spatial materials’ capable of completely encapsulating various molecules. When a molecule is isolated entirely from its external environment, it often exhibits unexpected physical properties and reactivity. I have high expectations for the unforeseen functions that can emerge from this.

As an example, we used self-assembly to create a crystalline material composed of palladium cages. This material led to the development of the ‘crystalline sponge (CS) method’, a technology that allows for the clear observation of the structures of various organic compounds absorbed within it. The CS method is now beginning to be utilized in drug discovery research by pharmaceutical companies. While the word ‘materials’ often brings to mind production on a kilogram or tonne scale, our CS method requires only about one microgram of the crystalline sponge. From that tiny amount, pharmaceuticals worth billions of dollars can potentially be born. Looking at it differently, we have imparted massive economic value to a minute amount of palladium, opening up an entirely unprecedented avenue for the utilization of precious metals.

Thanks for your involvement in the Palladium Global Science Award so far. What impact do you see the competition having on cooperation between government, industry research and business?

This competition recognizes not only research with immediate, visible applications and commercialization but also fundamental research based on the discovery of new principles and phenomena that overturn conventional wisdom. I hope that this will lead to a deeper understanding of such fundamental research efforts by industry and government, ultimately fostering new forms of cooperation among government, industry and academia.

Applications for the second edition of the Palladium Global Science Award are open until 31 July. The $350,000 prize pool will once again be awarded to five winners across the three nominations: Best Scientific Development, Best Scientific Article and Best Applied Concept. We recently published an article highlighting insights from Chair of the International Expert Council Professor Francis Verpoort on how to prepare a strong application.