Catalytic self-folding of 2D structures through cascading magnet reactions

While thousands of proteins involved in development of the human body are capable of self-assembling in a distributed manner from merely 20 types of amino acid, macroscopic products that can be assembled spontaneously from ‘alive’ components remains an aspiration in engineering. To attain such a mechanism, a major challenge lies in understanding which attributes from the bio-molecular realm must be leveraged at the macro-scale. Inspired by protein folding, we present a centimetre-size 1D tile chain whose self-folding processes are directed by structure-embedded magnetic interactions, which can theoretically self-assemble into convex 2D structures of any size or shape without the aid of a global ‘controller’. Each tile holds two magnets contained in paths designed to control their interactions. Once initiated by a magnetic unit (termed Catalyst), the chain self-reconfigures by consuming magnetic potential energy stored between magnet pairs, until the final 2D structure is reached at an energetic minimum. Both simulation and experimental results are presented to illustrate the method’s efficacy on chains of arbitrary length. Results demonstrate the promise of a physically implemented, bottom-up, and scalable self-assembly method for novel 2D structure manufacturing, bridging the bio-molecular and mechanical realms.


Recommendation? Accept as is
Comments to the Author(s) The research described in this paper -on an approach to generating 2D structures from an initial 1D line of tiles through cascading magnetic interactions -is interesting, novel and scientifically sound. I believe it constitutes a solid contribution to the literature. The paper is well written, the motivations are clear and the authors show a proper understanding of the strengths and weaknesses of the approach.
In my opinion the authors have more than adequately responded to the original reviewers' comments.
As a biologically inspired approach to structure formation this is interesting and potentially important work. The authors have produced a cleverly designed experimental framework that has been used to demonstrate that the basic principles of their approach do indeed work.

Review form: Reviewer 2
Is the manuscript scientifically sound in its present form? Yes

Are the interpretations and conclusions justified by the results? Yes
Is the language acceptable? Yes

Recommendation?
Accept with minor revision (please list in comments)

Comments to the Author(s)
The nomenclature used in this paper is not an easy one to follow for Biological Researchers. In fact there are statements that might seem a bit off. Take for example "One example of biological self-assembly can be found in the assembly of DNA nucleotide bases into the correct A-T and C-G pairs in a highly stochastic process, demonstrating a high level of addressabilty." I would argue that DNA replication is NOT a stochastic process (unless you consider any chemical reaction a highly stochastic process). A few other examples of this type of nomenclature clash exist and should be clarified. Nomenclature should also be defined early on if biologists are to engage with the paper from the beginning.
There are also some typos and the manuscript should be passed through a word corrector (e.g. repariable should be repairable).
Finally, I would like to see some films of experiments with more than three tiles. It is stated that you performed experiments with up to 10 tiles, so why not show some of these, with 5 or 6 tiles?

04-Jun-2019
Dear Professor Southern On behalf of the Editors, I am pleased to inform you that your Manuscript RSOS-182128 entitled "Catalytic Self-Folding of 2D Structures through Cascading Magnet Reactions" has been accepted for publication in Royal Society Open Science subject to minor revision in accordance with the referee suggestions. Please find the referees' comments at the end of this email.
The reviewers and handling editors have recommended publication, but also suggest some minor revisions to your manuscript. Therefore, I invite you to respond to the comments and revise your manuscript.
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Reviewer comments to Author: Reviewer: 1 Comments to the Author(s) The research described in this paper -on an approach to generating 2D structures from an initial 1D line of tiles through cascading magnetic interactions -is interesting, novel and scientifically sound. I believe it constitutes a solid contribution to the literature. The paper is well written, the motivations are clear and the authors show a proper understanding of the strengths and weaknesses of the approach.
In my opinion the authors have more than adequately responded to the original reviewers' comments.
As a biologically inspired approach to structure formation this is interesting and potentially important work. The authors have produced a cleverly designed experimental framework that has been used to demonstrate that the basic principles of their approach do indeed work.

Reviewer: 2
Comments to the Author(s) The nomenclature used in this paper is not an easy one to follow for Biological Researchers. In fact there are statements that might seem a bit off. Take for example "One example of biological self-assembly can be found in the assembly of DNA nucleotide bases into the correct A-T and C-G pairs in a highly stochastic process, demonstrating a high level of addressabilty." I would argue that DNA replication is NOT a stochastic process (unless you consider any chemical reaction a highly stochastic process). A few other examples of this type of nomenclature clash exist and should be clarified. Nomenclature should also be defined early on if biologists are to engage with the paper from the beginning.
There are also some typos and the manuscript should be passed through a word corrector (e.g. repariable should be repairable).
Finally, I would like to see some films of experiments with more than three tiles. It is stated that you performed experiments with up to 10 tiles, so why not show some of these, with 5 or 6 tiles?