Anions Enhance Rare Earth Adsorption at Charged Surfaces
May 14, 2020
J. Phys. Chem. Lett., 11, 11, 4436-4442 (2020)
Ion adsorption and transfer at aqueous interfaces are very important in various processes. However, the mechanism is complicated and not well understood since many driving forces play roles here. Combining nonlinear light scattering and surface X-ray scattering techniques, researchers from Argonne National Laboratory studied the rare earth ions adsorption at negatively charged surfaces with various anions in the solution. They discovered that specific anions can absorb to the surface and therefore enhance the cations adsorption when ion-specific effects dominate over electrostatic interactions.
Materializing rival ground states in the barlowite family of kagome magnets: quantum spin liquid, spin ordered, and valence bond crystal states
April 29, 2020
npj: Quantum Materials, 5, 23 (2020)
The spin kagome antiferromagnet is considered an ideal host for a quantum spin liquid (QSL) ground state. The scientists found that when the bonds of the kagome lattice are modulated with a periodic pattern, new quantum ground states emerge.
Competing Absorption of Surfactants and Antibodies to the Water Surface
February 4, 2020
ACS Appl. Mater. Interfaces 2020, 12, 8, 9977-9988 (2020)
Monoclonal antibodies have become leading candidates to be used as therapeutics due to the exceptional selectivity and binding affinity for their molecular targets. However, the absorption of antibodies at air-water interfaces during various processes and the subsequent denaturation reduces their lives. To overcome this problem, the pharmaceutical industry uses surfactants to compete with antibodies for adsorption onto the surface. A research group from CCNY used pendant bubble tensiometry and X-ray reflectivity techniques to characterize the adsorption process of antibodies and surfactants.
*Reprinted with permission from ACS Appl. Mater. Interfaces 2020, 12, 8, 9977-9988. Copyright 2020 American Chemical Society.
In situ visualization of loading-dependent water effects in a stable metal–organic framework
December 02, 2019
Nature Chemistry (2019)
Even for MOFs that are highly stable in humid environments, a static representation of the framework structure may not be sufficient to understand the observed stability. This work has shown that the DMOF-TM framework has a dynamic and reversible structural response to water guest molecules, observed in changes in the unit cell parameters, microstrain, vibrational spectra and atomic structure. These changes manifest themselves at low guest loading and continue to change in response to guest loading.
Nanosheets Synthesis under Mixed Surfactants
October 11, 2019
Chem. Mater. 2019, 31, 21, 9040-9048
Two-dimensional monocrystalline oxide nanomaterials have a great impact on material innovation and property advancement. However, creating them with fine control remains a grand challenge. Inspired by the biomineralization processes, researchers from the University of Wisconsin-Madison were able to synthesize the monocrystalline 2D nanosheets under the mix-charges amphiphilic monolayer. The growth process was monitored by in-situ grazing incidence X-ray diffractions at NSF’s ChemMatCARS.
*Reprinted with permission from Chem. Mater. 2019, 31, 21, 9040-9048. Copyright 2019 American Chemical Society.
Characterization of a Reactive Rh2 Nitrenoid by Crystalline Matrix Isolation
September 24, 2019
J. Am. Chem. Soc. 2019, 141, 41, 16232 –16236
The scientists from Texas A&M University and The University of Chicago report the first X-ray crystal structure of a reactive Rh2 nitrenoidis, enabled by N2 elimination from an organic azide ligand within a single-crystal matrix. The resulting high-resolution structure displays metrical parameters consistent with a triplet nitrene complex of Rh2. The demonstration of facile access to reactive metal nitrenoids within a crystalline matrix provides a platform for structural characterization of the transient species at the heart of C–H functionalization.
The Role of Ligands on Bio-Nano Interactions
Nanoparticles targeting biological membranes leads to multiple biomedical effects. The coating ligands are known to affect the nanoparticle-membrane interaction. However, the molecular mechanisms of this modulation remain unresolved. Researchers from Chinese Academy of Sciences, Columbia University, and University of Chicago combined X-ray liquid surface scattering and MD simulations to investigate the role of coating ligands on the nanoparticle-membrane binding at the water surface.
Phospholipid-Phospholipase Interaction on Water Surface
Overexpressed intrinsic enzymes such as secretory phospholipase A2 (sPLA2) have been used to trigger the local drug release from lipid vesicles. sPLA2 can catalyze the hydrolysis of one tail of a phospholipid, which yields equimolar fatty acid and lysophospholipid. However, little is known about this process on the molecular length scale. A recent study by researchers from University of Illinois at Chicago uncovered molecular interactions of phospholipids with enzymes.