The structural stabilities of the molecular chain sheets constituting the crystal structures of the cellulose allomorphs Iα, Iβ, II, and IIII were investigated by density functional theory (DFT) optimization of the isolated chain sheet models with finite dimensions. The DFT-optimized chain sheet models of the two native cellulose crystals developed a right-handed twist with a similar amount of twisting. The DFT-optimized cellulose II (010) and (020) models twisted in opposite directions with right- and left-handed chirality, respectively. The cellulose IIII (1-10) model retained the initial flat structure after the DFT-optimization. The structural features of the DFT-optimized chain sheet models were reflected in the structures of the parent crystal models observed in solvated molecular dynamics (MD) simulations. The minor conformations of the hydroxymethyl groups proposed in the real crystal structures were detected in the MD crystal models and the DFT-optimized (010) model of cellulose II. The crystal chain packing and crystal conversions are interpreted in terms of principal chain sheet stacking.
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Langmuir
January 2025
Jiangsu Collaborative Innovation Center of Biomedical Functional Materials, Jiangsu Key Laboratory of Bio-functional Materials, Department of Materials Science and Engineering, School of Chemistry and Materials Science, Nanjing Normal University, Nanjing 210023, P. R. China.
Steric stabilization and lubrication give loop polymer brushes enhanced antifouling properties. In the study, linear zwitterionic poly(NMASMCMS) brushes were first constructed on a poly(ethylene terephthalate) (PET) surface through surface-initiated reversible addition-fragmentation chain-transfer (SI-RAFT) polymerization. The tethered linear brushes on sheets were then thiolated with ethanolamine, followed by oxidation to form loop brushes.
View Article and Find Full Text PDFLangmuir
December 2024
Department of Chemical Engineering, Hanyang University, Seoul 04763, Korea.
Covalent organic nanotubes offer enhanced stability, robustness, and functionality, compared to their noncovalent counterparts. This study explores constructing polydiacetylene (PDA) nanotubes using a two-step process: self-assembly via noncovalent interactions followed by UV-induced polymerization of a diacetylene template. A promising building block consisting of a hydrogen-bonding headgroup, barbituric acid, linked to a linear diacetylene chain was prepared.
View Article and Find Full Text PDFAdv Healthc Mater
December 2024
Evolved.Bio, 280 Joseph Street, Kitchener, Ontario, N2G4Z5, Canada.
Progress in understanding the underlying mechanisms of muscular dystrophies is hindered by the lack of pathophysiologically relevant in vitro models. Here, an entirely scaffold-free anchored cell sheet engineering platform is used to create patient-specific three-dimensional (3D) skeletal muscle in vitro models. This approach effectively replicates mature muscle phenotypes and tissue- and disease-specific extracellular matric (ECM).
View Article and Find Full Text PDFJ Chem Phys
December 2024
Department of Chemistry, University of Chicago, Chicago, Illinois 60637, USA.
Peptoids (N-substituted glycines) are a class of sequence-defined synthetic peptidomimetic polymers with applications including drug delivery, catalysis, and biomimicry. Classical molecular simulations have been used to predict and understand the conformational dynamics of single chains and their self-assembly into morphologies including sheets, tubes, spheres, and fibrils. The CGenFF-NTOID model based on the CHARMM General Force Field has demonstrated success in accurate all-atom molecular modeling of peptoid structure and thermodynamics.
View Article and Find Full Text PDFActa Crystallogr E Crystallogr Commun
October 2024
Osaka Research Institute of Industrial Science and Technology, 1-6-50 Morinomiya, Joto-ku, Osaka 536-8553, Japan.
The title compound, [Zn(CHClNO)Cl], is a dinuclear zinc(II) complex with three chlorido ligands and one penta-dentate ligand containing quinolin-8-olato and bis-(pyridin-2-ylmeth-yl)amine groups. One of the two Zn atom adopts a tetra-hedral geometry and coordinates two chlorido ligands with chelate coord-ination of the N and O atoms of the quinolin-8-olato group in the ligand. The other Zn atom adopts a distorted trigonal-bipyramidal geometry, and coordinates one chlorido-O atom of the quinolin-8-olato group and three N atoms of the bis-(pyridin-2-ylmeth-yl)amine unit.
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