EDITORIAL

RINUS BROXTERMAN Member of Chimica Oggi/Chemistry Today Scientific Advisory Board DSM Chemical Technology R&D B.V., Urmonderbaan 22, 6167 RD Geleen, Netherlands

Rinus Broxterman

The rise of supramolecular chemistry in industry

The relevance of non-covalent molecular interactions is apparent in our daily life: they play crucial roles in natural occurring systems such as in photosynthesis, protein folding, and indeed the action of a cell as a whole. Furthermore, these interactions have also proven their potential in industrial applications as they have played – and are still playing – an important role in ascertaining the desired properties of the functional assemblies/products created. En route to realizing its full potential it is not surprising that in the last two decades a tremendous boost in academic contributions has been observed, resulting in a status of supramolecular chemistry leaving its embryonic development phase. A major reason for this development is that the underlying scientifi c themes and challenges are being unravelled and mastered. Most importantly, the fi eld is unfolding its true strength in the ability to upfront design non-covalent interactions in the molecular structure to steer the assembly of molecules towards a morphology (mesoscopic structure) that – in its turn – is required to deliver the desired macroscopic properties. As a result of this ability, supramolecular chemistry has the potential to act across the design chain of many different types of products, linking the fundamentals of molecular chemistry to product development (and the value chain from small molecule building blocks to full macroscopic products). The consequence of linking the molecular scale to the macroscopic scale is that knowledge from both ends of the spectrum are necessary to be successful. Not only the necessity to interact with a variety of different disciplines makes supramolecular chemistry a challenging and multidisciplinary science; it is also acting at a length scale which is diffi cult to visualize with the current analytical equipment. It is exactly in between the nanometer and micrometer scales where detailed analysis remains a challenge. In order to overcome this hurdle, more recently supramolecular chemists are adopting techniques typically applied in the fi eld of biophysics to visualize the synthetic analogues as well as understand their formation and behaviour in solution and in the solid state. And as important steps are still to be made, it creates an exciting area of research in which large progress can be expected in the near future. The examples listed in this issue and the July/Aug one highlight several advances supramolecular chemistry has made through recent years in the fi elds of 1) biomedical applications, 2) synthesis, 3) self-healing and 4) smart surfaces. This is just a limited overview of the different application areas in reach by skilfully exploiting the principles of supramolecular chemistry. The large amount of techniques that is required to provide a detailed understanding of the material at hand clearly demonstrates the multidisciplinary nature of this science. As a result, almost of the world-leading academic institutions in the fi eld of supramolecular chemistry aim to bring together these many different areas of expertise. These are not only disciplines in the fi eld of chemistry such as organic chemistry and catalysis or polymer chemistry, but also physics, mathematics, biomedical engineering, medical schools, biophysics and more, are combined in order to be able to tackle the basic principles of this challenging area. Especially the work performed in the last years has led to a more general description of the basic principles in the thermodynamics and kinetics of supramolecular systems. Therefore this fi eld is slowly but surely evolving into an area where complex molecular architectures are being considered, and taken as challenge, to be designed and synthesized. As mentioned before, a lot of inspiration for these endeavours is drawn from Nature. For example, it is still a great challenge to perform for example multi-step one pot synthesis, or master sequence control in polymers, which are commonly encountered in Natural systems. The ability to design and produce these types of systems is now slowly becoming a major driver in the fi eld. Now, where does this leave the applicability of supramolecular chemistry in industry? As mentioned, non-covalent interactions are present either “by accident” (lot of historical cases) or by design in many products currently available on the market. In the (historic) ‘by accident’ cases, more (recent) detailed understanding afterwards revealed the supramolecular nature of the key product assembly features. The use of supramolecular chemistry will now help in the de novo design of these interactions and is able to bring together the macroscopic and molecular fi elds. For a structured approach of supramolecular chemistry within companies, a broad range of competences needs to be present. This includes small molecule and polymer chemistry, material sciences, physical chemistry, computational chemistry, biochemistry and a strong capability in analytics at all length scales. This makes product design and application based supramolecular chemistry design principles limited to companies mastering at least a signifi cant part of these competences in-house. Furthermore it asks for determination in the challenging task of creating a common language between the different disciplines in order to be able to harvest the great potential of supramolecular chemistry in the molecular design of macroscopic properties. Over the last two decades academics has paved the way in providing the ground works and structure in this new scientifi c discipline showing great potential for industrial application. It is now up to the relevant industries that have the capability to apply the principles of supramolecular chemistry to harvest its potential to either improve the current product portfolio or to dive into new yet not established products and markets.

4 Chimica Oggi - Chemistry Today - vol. 32(3) May/June 2014