Hierarchical Self-Assembly Pathways of Peptoid Helices and Sheets
January 12, 2022
Molecular dynamics simulations predict a hierarchical self-assembly pathway of peptoid sheets in evaporation-induced assembly: monomers first assemble disordered aggregates, then 1D helical rods, and finally 2D crystalline sheets. Predictions are supported by experimental observations using x-ray diffraction and atomic force microscopy.
Scientific Achievement
We use coarse-grained molecular dynamics simulations and experimental validation to establish a new mechanistic and thermodynamic understanding of the evaporation-induced assembly of peptoids into 2D nanosheets, and to identify conditions that stabilize previously unknown 1D helical rod intermediates.
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Significance and Impact
The results define new principles and guidance for the predictive design of peptoid-based nanomaterials.​
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Research Details
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MD simulations predict a hierarchical assembly pathway in which peptoid oligomers first assemble into disordered aggregates that next self-order into 1D chiral helical rods, which then assemble into 2D achiral crystalline nanosheets.
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Experimental observation of 1D rods in mixed solvent by SAXS and CD, and of 2D crystalline sheets in pure water by XRD and AFM, support computational predictions.