Science Highlights
Phospholipid-Phospholipase Interaction on Water Surface
April, 2019
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.
Element Selectivity of Solvent Extraction
February 2019
Solvent extraction technique has been widely used in mining and refinement of rare earths. Although all rare earths are chemically similar, the extraction efficiency increases as a function of atomic number. Combining MC simulation and X-ray fluorescence measurements at NSF’s ChemMatCARS, researchers from Northwestern University and The University of Chicago revealed the electrostatic origin of this selectivity.
Thermally Persistent High-Spin Ground States in Octahedral Iron Clusters
November 7, 2018
J. Am. Chem. Soc., 2018, 140 (48), pp 16792-16806
In this paper, a series of isostructural octahedral hexairon clusters are shown to display spin ground states varying from S = 9/2 to S = 11, marking thus the record of the highest spin states that remain isolated up to 300 K. Such behavior is attributed to double exchange manifested in the strongly delocalized clusters. Consequences of the latter are the hyperfine splitting of the Mössbauer spectrum at low temperature and the emergence of SMM behavior. As seen in the structural metrics, the existence of magnetic anisotropy can be predicted by the asymmetry of the [Fe6] octahedron and further manipulated by simple solvation of the cluster. The latter provides a pathway by which the magnetic behavior can be tuned and enhanced by simple exploration of other auxiliary ligands.
Ordering of Molecular Rotor Monolayer on Aqueous Surface
June 2018
BBA – Biomembranes, 2018, 1860, pp 1414-1423
Antimicrobial peptides (AMPs) target bacterial cells mainly by electrostatic interactions. Studies indicate that the hydrophobicity of AMPs plays an important role on the selectivity. By using the X-ray reflectivity technique at NSF’s ChemMatCARS and other characterization tools, researchers from Illinois Institute of Technology and New York University have investigated the molecular basis for peptoid interactions with bacterial and eukaryotic lipid membranes on the sub-nanometer scale.