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1. Anomalous Dynamics in Macromolecular Liquids

   https://doi.org/10.3390/polym14050856  

   Guenza, Marina G. (March 2022, Polymers)

   Macromolecular liquids display short-time anomalous behaviors in disagreement with conventional single-molecule mean-field theories. In this study, we analyze the behavior of the simplest but most realistic macromolecular system that displays anomalous dynamics, i.e., a melt of short homopolymer chains, starting from molecular dynamics simulation trajectories. Our study sheds some light on the microscopic molecular mechanisms responsible for the observed anomalous behavior. The relevance of the correlation hole, a unique property of polymer liquids, in relation to the observed subdiffusive dynamics, naturally emerges from the analysis of the van Hove distribution functions and other properties. 

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2. Revisiting macromolecular hydration with HullRadSAS

   https://doi.org/10.1007/s00249-022-01627-8  

   Fleming, Patrick J.; Correia, John J.; Fleming, Karen G. (January 2023, European Biophysics Journal)

   Hydration of biological macromolecules is important for their stability and function. Historically, attempts have been made to describe the degree of macromolecular hydration using a single parameter over a narrow range of values. Here, we describe a method to calculate two types of hydration: surface shell water and entrained water. A consideration of these two types of hydration helps to explain the “hydration problem” in hydrodynamics. The combination of these two types of hydration allows accurate calculation of hydrodynamic volume and related macromolecular properties such as sedimentation and diffusion coefficients, intrinsic viscosities, and the concentration-dependent non-ideality identified with sedimentation velocity experiments. 

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3. Macromolecular-clustered facial amphiphilic antimicrobials

   https://doi.org/10.1038/s41467-018-07651-7  

   Rahman, Md Anisur; Bam, Marpe; Luat, Edgar; Jui, Moumita Sharmin; Ganewatta, Mitra S.; Shokfai, Tinom; Nagarkatti, Mitzi; Decho, Alan W.; Tang, Chuanbing (December 2018, Nature Communications)

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4. Chirality transmission in macromolecular domains

   https://doi.org/10.1038/s41467-021-27708-4  

   Pandey, Shankar; Mandal, Shankar; Danielsen, Mathias Bogetoft; Brown, Asha; Hu, Changpeng; Christensen, Niels Johan; Kulakova, Alina Vitaliyivna; Song, Shixi; Brown, Tom; Jensen, Knud J.; et al (January 2022, Nature Communications)

   Abstract Chiral communications exist in secondary structures of foldamers and copolymers via a network of noncovalent interactions within effective intermolecular force (IMF) range. It is not known whether long-range chiral communication exists between macromolecular tertiary structures such as peptide coiled-coils beyond the IMF distance. Harnessing the high sensitivity of single-molecule force spectroscopy, we investigate the chiral interaction between covalently linked DNA duplexes and peptide coiled-coils by evaluating the binding of a diastereomeric pair of three DNA-peptide conjugates. We find that right-handed DNA triple helices well accommodate peptide triple coiled-coils of the same handedness, but not with the left-handed coiled-coil stereoisomers. This chiral communication is effective in a range (<4.5 nm) far beyond canonical IMF distance. Small-angle X-ray scattering and molecular dynamics simulation indicate that the interdomain linkers are tightly packed via hydrophobic interactions, which likely sustains the chirality transmission between DNA and peptide domains. Our findings establish that long-range chiral transmission occurs in tertiary macromolecular domains, explaining the presence of homochiral pairing of superhelices in proteins. 

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5. Nanoparticle Brushes: Macromolecular Ligands for Materials Synthesis

   https://doi.org/10.1021/acs.accounts.3c00160  

   Hueckel, Theodore; Luo, Xin; Aly, Omar F.; Macfarlane, Robert J. (July 2023, Accounts of Chemical Research)

   In this Account, we describe our recent work in developing polymer brush coatings for nanoparticles, which we use to modulate particle behavior on demand, select specific nanoscopic architectures to form, and bolster traditional bulk polymers to form stronger materials by design. Distinguished by the polymer type and capabilities, three classes of nanoparticles are discussed here: nanocomposite tectons (NCTs), which use synthetic polymers end-functionalized with supramolecular recognition groups capable of directing their assembly; programmable atom equivalents (PAEs) containing brushes of synthetic DNA that employ Watson–Crick base pairing to encode particle binding interactions; and cross-linkable nanoparticles (XNPs) that can both stabilize nanoparticles in solution and polymer matrices and subsequently form multivalent cross-links to strengthen polymer composites. We describe the formation of these brushes through “grafting-from” and “grafting-to” strategies and illustrate aspects that are important for future advancement. We also examine the new capabilities brushes provide, looking closely at dynamic polymer processes that provide control over the assembly state of particles. Finally, we provide a brief overview of the technological applications of nanoparticles with polymer brushes, focusing on the integration of nanoparticles into traditional materials and the processing of nanoparticles into bulk solids. 

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