An update from Molecular Systems Design & Engineering

Welcome to the second volume of Molecular Systems Design & Engineering, published jointly by the Royal Society of Chemistry and the Institution of Chemical Engineers. When we published our inaugural issue 8 months ago we set out our intention to publish research which uses a molecular-level design or optimization approach to address technological problems (see DOI: 10.1039/C6ME90001A). Many of the articles we have published since then have related to specific technologies, including solar cells, the processing of nuclear waste, and a number of biomedical applications, from drug delivery to synthetic biology, photomedicine and biosensing (see Miller et al. [DOI: 10.1039/C6ME00032K] for an example of the latter). We have also published a number of papers which do not target a specific application but, rather, apply a molecular design approach to provide fresh insight into the structure–property relationship of a particular class of molecular systems (for example, see Piccinini et al. [DOI: 10.1039/C6ME00016A]).

We are pleased that the first issues of the journal have demonstrated this diversity, and we thank all those who have supported the journal thus far. We also want to take this opportunity to highlight just some of the emerging research frontiers in which molecular engineering principles are playing a prominent role.

Material design and engineering

With support from the US government under the Materials Genome Initiative, a considerable number of new efforts have aimed to design and develop materials by relying on models and vast amounts of data to accelerate the cycle of design, experimentation, testing and deployment. Noteworthy examples have appeared in the areas of metals and metal oxides,¹ ceramics, polymers, and amorphous materials (glasses).^2,3 Efforts are growing in this area throughout the world, and new questions are emerging: can one design not only target materials, but also non-equilibrium processes to target non-equilibrium (but metastable) states of materials?

Triggerable or addressable materials

New efforts are being aimed at developing materials systems that can achieve a prescribed function (e.g. detect a toxin, or release a chemical in response to an external cue) when exposed to distinct engineered signals. Examples range from metallic or polymeric structures that undergo a carefully prescribed shape change when exposed to external forces (stress, pH change),⁴ to liquid crystals that undergo a morphological (and colorimetric) transition when exposed to a toxin or a biological molecule.⁵ This work is in its infancy – can one now design materials that perform multiple functions and respond to multiple cues?

Material origami

It is now possible to engineer folds (origami) and cuts (kirigami) to control the transformation of 2D materials into prespecified 3D structures. Profound theoretical work has been developed to programme such cuts and intriguing experimental work has provided proof-of-concept demonstrations,^6,7 but we have yet to mimic the complexity that has been achieved in traditional (paper) origami, where complex structures are created by Japanese masters. What are the algorithms that these masters use? Can they be expressed in a mathematical form? There are exciting applications here in fields ranging from biology to medicine to space exploration (e.g. antennas that fold into tight packages).

Quantum engineering

Major resources are being invested in materials for quantum information. Thus far a key approach has been to exploit nitrogen vacancy centres in diamonds as solid-state qubits, but this is demanding. Considerable efforts have been aimed at discovering alternative materials through materials design strategies and new discoveries have been promising.⁸ The questions that seem to be emerging are whether we will be able to control such materials at room temperature, control coherence, and deploy such new systems in applications.

Additive manufacturing

We are undergoing a revolution in manufacturing, where the aim is to produce complex material parts on demand, when needed, according to ever-changing specifications. Three-dimensional printing, for example, has enable much of this revolution. Such platforms apply to metals, semiconductors, and polymers. There are newer forms of additive manufacturing that are highly promising (for example, based on photopolymerization). The materials that are being used in additive manufacturing are generally materials that were conceived for traditional, bulk manufacturing. There are tremendous opportunities for the design of new materials and manufacturing processes that will take advantage of emerging opportunities in that space.^9,10

We hope that Molecular Systems Design and Engineering will be a venue for future work on such problems, and we look forward to further enhancing communication between the science and engineering communities.

Juan de Pablo, Editorial Board Chair

Neil Hammond, Executive Editor

References

1. T. M. Pollock, Nat. Mater., 2016, 15, 809–815.
2. Y. Qiu, L. W. Antony, J. J. de Pablo and M. D. Ediger, J. Am. Chem. Soc., 2016, 138, 11282–11289.
3. D. Shakeel, D. M. Walters, I. Lyubimov, J. J. de Pablo and M. D. Ediger, Proc. Natl. Acad. Sci. U. S. A., 2015, 112, 4227–4232.
4. J. W. Rocks, N. Pashine, I. Bischofberger, C. P. Goodruch, S. R. Nagel and A. J. Liu, Biophys. J., 2016, 110, 54A.
5. E. Bukusoglu, M. Bedolla Pantoja, P. C. Mushenheim, X. Wang and N. L. Abbott, Annu. Rev. Chem. Biomol. Eng., 2016, 7, 163–196.
6. B. Gin-ge Chen, B. Liu, A. A. Evans, J. Paulose, I. Cohen, V. Vitelli and C. D. Santangelo, Phys. Rev. Lett., 2016, 116, 135501.
7. P. M. Reis, F. López Jiménez and J. Marthelot, Proc. Natl. Acad. Sci. U.S.A., 2015, 112, 12234–12235.
8. H. Seo, A. L. Falk, P. V. Klimov, K. C. Miao, G. Galli and D. D. Awschalom, Nat. Commun., 2016, 7, 12935.
9. R. Janusziewicz, J. Tumbleston, A. L. Quintanilla, S. J. Mecham and J. M. DeSimone, Proc. Natl. Acad. Sci. U.S.A., 2016, 113(42), 11703–11708.
10. R. L. Truby and J. A. Lewis, Nature, 2016, 540, 371–378.

---