Hygroscopy of Single‐Stranded DNA Nano‐Brushes: Atomic Workings of its Hydration‐Induced Deformation. Issue 34 (17th October 2022)

• Record Type: Journal Article
• Authors: Ortega, Maria; Vilhena, J. G.; Pérez, Rubén
• Is Part Of: Advanced materials interfaces. Volume 9:Issue 34(2022)
• Page Start: n/a
• Page End: n/a
• Publication Date: 2022-10-17
• Subjects: hydration -- hygroscopic properties -- mechanical responses -- molecular dynamics -- ssDNA polymer brushes; Materials science -- Periodicals; 620.11
• DOI: 10.1002/admi.202201272
• Languages: English
• ISSNs: 2196-7350

Abstract

Abstract: Hydration control of structure and mechanical properties is a process widely exploited in living organisms for key biological functions and, most recently, also in man‐made smart materials. Here, the challenge of unveiling the underlying atomistic mechanisms of this phenomenon using all‐atom Molecular Dynamics (MD) simulations to model the hygroscopic properties of polymer‐brushes composed by single‐stranded DNA (ssDNA) molecules is faced. The simulations identify three swelling regimes with a markedly different mechanical response. This evolution is produced by the competition between the formation of additional water–ssDNA and water–water hydrogen bonds, in a subtle interplay with the co‐evolving structure of the ssDNA SAM. This cooperative interaction between conformational and hydration degrees of freedom should be applicable to other polymer brushes and related hydrogen‐bonded systems. The results have direct implications for the use of ssDNA SAMs as sequencing devices, explaining the crucial role of the polymer‐brush density in the SAM collective response to hydration, and for the alternative design of hygroscopic materials, that exploit the extreme hygroscopic power of biological polymers like ssDNA brushes. Abstract : Controlling shape, size, and stiffness through hydration is a phenomenon ingeniously explored in Nature (e.g., plants). However, beyond recognizing it, understanding such process is critical to harness it in emerging technologies (e.g., smart materials). Here, molecular dynamics simulations provide an atomically detailed understanding of long‐range hydration‐induced deformations occurring in DNA polymer brushes, thus connecting supramolecular interactions with shape‐shifting properties.