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Results for “self assembly”
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Pickering Emulsions of Self-Assembled Lead Sulfide Quantum Dots with Janus-Ligand Shells as Nanoreactors for Photocatalytic Reactions
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Self-Assembly Interactions in Magnetite-Coated Cellulose Nanocrystals: Implications for Magnetic Hyperthermia Applications
Magnetic cellulose nanocrystal (MCNC) nanocomposites are promising sustainable and biocompatible platforms for magnetic hyperthermia; however, the molecular mechanisms governing Fe 3 O 4 adsorption and deposition onto CNCs remain poorly understood. Here, sulfated (S-CNC) and TEMPO-oxidized CNCs (T-CNC) were used to prepare nanocomposites at 1:2 and 1:4 CNC:Fe 3 O 4 mass ratios, enabling a systematic evaluation of how surface chemistry and nanoparticle loading dictate interfacial interactions and magneto-colloidal behavior. Bare magnetite nanoparticles were 21 ± 5 nm by TEM but grew to 144 ± 18 in the DLS measurement at pH 7. The S-CNC nanocomposites had hydrodynamic sizes between 144 and 210 nm, not much larger than the 140 nm long CNC rods, suggesting an enhanced dispersion stability compared to Fe3O4 alone. X-ray photoelectron spectroscopy combined with density functional theory revealed that −OH and −COOH groups drive electrostatic adsorption with charge transfer from Fe 3 O 4 to the CNC surface, while T-CNCs showed more favorable adsorption energies and evidence of covalent Fe−O bonding. Vibrating sample magnetometry demonstrated superparamagnetic behavior for all samples, with S-CNC/Fe 3 O 4 1:4 and 1:2 displaying saturation magnetizations of 78 and 77 emu/g-Fe 3 O 4 , close to the 83 emu/g of bare magnetite. The T-CNC composites showed lower (60 and 66 emu/g-Fe3O4) saturation magnetizations. Zero-field-cooled/field-cooled measurements resulted in a blocking temperature of 112 K for all samples, except T-CNC/Fe 3 O 4 1:2 (100 K). Magnetic hyperthermia studies revealed that specific absorption rate (SAR) increased with field strength and Fe 3 O 4 content; however, S-CNC/Fe 3 O 4 (1:2) achieved the highest intrinsic SAR per gram of Fe 3 O 4 (649 W/g-Fe 3 O 4 ) likely due to its anisotropy and fast magnetic relaxation. Cytotoxicity assays confirmed that all nanocomposites were nontoxic toward mammalian cells. These results establish quantitative structure−property relationships between CNC surface chemistry, interfacial bonding mechanisms, and magnetic heating performance, providing a foundation for rational design of biocompatible magnetic nanocomposites for hyperthermia and related applications.
Self-Assembly of Charged Diblock Copolymers with Reduced Backbone Polarity
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Superlattices are Greener on the Other Side: How Light Transforms Self-Assembled Mixed Halide Perovskite Nanocrystals
Perovskite nanocrystal superlattices (NC SLs) are the nearest real-world approximations to monodisperse NC ensembles. NC SLs thus represent ideal model systems for evaluating the optical and structural stability of CsPb(I 1– x Br x ) 3 NCs at a macroscopic level. Here, photoinduced changes to CsPb(I 1– x Br x ) 3 NC SLs (0 < x < 1.0) are probed via in situ photoluminescence, X-ray diffraction, and electron microscopy. We find that prolonged (~10–20 h) ultraviolet–visible irradiation causes irreversible PL blueshifts, photobrightening, and crystal structure contractions. These changes stem from gradual photoinduced I 2 sublimation, which transforms CsPb(I 1– x Br x ) 3 into CsPbBr 3 . Despite eliminating half of the initial halides from individual CsPb(I 0.53 Br 0.47 ) 3 particles, NCs within SLs remarkably preserve their initial crystallinity, cuboidal shapes, edge lengths, and size distributions. This work illustrates compositional control toward generating precisely engineered perovskite NC SLs. It also highlights iodide photo-oxidation as a hurdle that must be overcome if mixed halide perovskite nanomaterials are to be applied beyond fundamental studies.
Anti-persister and Anti-biofilm Activity of Self-Assembled Antimicrobial Peptoid Ellipsoidal Micelles
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Supramolecular Self-Assembly of Perylene Bisimide-Based Rigid Giant Tetrahedra
Abstract not provided
Block Copolymer Self-Assembly-Directed and Transient Laser Heating-Enabled Nanostructures toward Phononic and Photonic Quantum Materials
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Computer Simulations Show That Liquid–Liquid Phase Separation Enhances Self-Assembly
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Correction to “Self-Assembly of Accumulated Sphingolipids into Cytotoxic Fibrils in Globoid Cell Leukodystrophy and Their Inhibition by Small Molecules in Vitro”
Dr. Laor Bar-Yosef was significantly involved in the introduction and use of the Raman microspectroscopy part of this project. She was a major contributor to the novel conceptual use of this technology for detecting and monitoring sphingolipids in vitro and in cells. As expected from her deep involvement, Dr. Laor Bar-Yosef took part in analyzing the corresponding results.
Divergent Self-Assembly Pathways to Hierarchically Organized Networks of Isopeptide-Modified Discotics under Kinetic Control
Abstract not provided