Monodisperse microgels were synthesized by a microfluidic setup and used as a sacrificial template for the fabrication of "giant" hollow polyelectrolyte capsules with rigid walls consisting of covalently cross-linked polyelectrolytes and metal nanoparticles. First, a simple tubing-needle-based microfluidic system is utilized to produce size-monodisperse, degradable "giant" microgels consisting of dextran chains linked via carbonate esters. Second, these monodisperse microgels are subjected to a layer-by-layer coating of negatively charged platinum nanoparticles (Pt(NP)'s) and a positively charged diazoresin (DAR). Three bilayers of Pt(NP)'s and DAR are used to obtain a stable membrane on the microgels. Finally, the sacrificial dextran-based microgel cores are smoothly hydrolyzed and removed without rupture of the polyelectrolyte membrane due to the covalently linked hybrid polyelectrolyte/nanoparticle nature of the membrane. Scanning electron and confocal microscopy are used to characterize the capsules. The capability of encapsulating materials of interest is also shown by the addition of fluorescent polystyrene particles to the monomer mixture and subsequent visualization of embedded polystyrene particles in coated microgels after microfluidic polymerization and layer-by-layer coating. The obtained "giant" microcapsules are envisaged to be used as microreactors or drug-delivery systems.
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Biochim Biophys Acta Biomembr
February 2025
Institute of Life and Environmental Sciences, University of Tsukuba, 1-1-1 Tennodai, Tsukuba, Ibaraki 305-8572, Japan.
Unlike homogeneous liposomes, phase-separated liposomes have the potential to be attractive soft materials because they exhibit different properties for each phase. In this study, phase separation was observed when liposomes were prepared using 1,2-dioleoyloxy-3-trimethylammonium propane chloride (DOTAP), 1,2-distearoyl-sn-glycero-3-phosphocholine (DSPC), and cholesterol. The pH of the DOTAP-rich phase was evaluated using a coumarin derivative, and measurements showed that DOTAP molecules accumulated hydroxyl ions (OH) in the DOTAP-rich phase.
View Article and Find Full Text PDFNat Commun
November 2024
IMDEA Materials Institute, Getafe, Madrid, Spain.
Systems with broken continuous symmetry in ideal lattices cannot be rectified through rearrangement or deformation. Topological metamaterials featuring nontrivial, artificially induced phase transitions have emerged as pivotal constituents for engineering these topological defects, which, until now, have mostly been experimentally realized in linear or planar configurations. Buckminster Fuller lent his name to the C ball-shaped carbon allotrope, which is not only the roundest molecule in existence but also embodies 3D topological defects.
View Article and Find Full Text PDFJ Am Chem Soc
August 2024
Guangdong Provincial Key Laboratory of Carbon Dioxide Resource Utilization, School of Chemistry, South China Normal University, Guangzhou, Guangdong 510006, China.
The construction of isotypic high-nuclearity inorganic cages with identical pristine parent structure and increasing nuclearity is highly important for molecular growth and structure-property relationship study, yet it still remains a great challenge. Here, we provide an in situ growth approach for successfully synthesizing a series of new giant hollow polymolybdate dodecahedral cages, , , and , whose structures are growth based on giant polymolybdate cage . Remarkably, they show two pathways of nuclear growth based on , that is, the growth of 10 and 20 Mo centers on the inner and outer surfaces to afford and , respectively, and the growth of 10 Mo centers both on the inner and outer surfaces to give .
View Article and Find Full Text PDFJ Am Chem Soc
June 2024
Institute of Environmental Research at Greater Bay Area, Key Laboratory for Water Quality and Conservation of the Pearl River Delta, Ministry of Education, Guangzhou Key Laboratory for Clean Energy and Materials, Guangzhou University, Guangdong 510006, China.
Molecular self-assembly is a widely recognized approach for fabricating biomimetic functional nanostructures. Here, we report the synthesis of two giant hollow coronoid-like supramolecular hexagons, and . These hexagons feature large cavities, showcasing unique inner and outer hexagons fixed by specific connectivities for enhanced stability and high metal center density.
View Article and Find Full Text PDFChemosphere
June 2024
College of Environment and Safety Engineering, Qingdao University of Science and Technology, Qingdao, Shandong, 266042, PR China. Electronic address:
The wide application of flexible polyurethane foam (FPUF) poses a giant challenge to human society in terms of fire prevention and environmental pollution. To solve this problem, the lignocellulose-based P-N flame retardant (LFPN) has been developed using mechanochemical methods. It was found that FPUF treated using LFPN exhibited good flame retardancy, but suffered from high smoke generation and toxicity.
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