Superior low temperature activity over α-MnO/β-MnOOH catalyst for selective catalytic reduction of NO with ammonia.

Manganese octahedral molecular sieves with an α-MnO crystal structure (OMS-2) and their related materials have attracted significant attention for the selective catalytic reduction of NO using NH (NH-SCR) at low temperatures. Further lowering their operating temperature should be an effective method to develop an environmentally friendly de-NO system; however, their catalytic activity at low temperatures, especially below 100 °C, remains poor. This study describes a post-synthetic approach to develop Mn-based catalysts superior to those in the literature that operate at ultralow temperatures.

Selective inhibition of cancer cell migration using a pH-responsive nucleobase-modified DNA aptamer.

Because of the extracellular acidic microenvironment of cancer cells, many pH-responsive molecules have become indispensable materials for bioanalysis and targeted therapy development. pH-Responsive DNA aptamers, which selectively bind to target proteins in cancer cells, have become a key research target in the therapeutic field. However, conventional pH-responsive aptamers have fatal drawbacks, such as complex structures, sequence limitation, and difficulties in mass production, as they require special nucleic acid structures, including the i-motif and DNA triplex.

Pd-incorporated polyoxometalate catalysts for electrochemical CO reduction.

Polyoxometalates (POMs), representing anionic metal-oxo clusters, display diverse properties depending on their structures, constituent elements, and countercations. These characteristics position them as promising catalysts or catalyst precursors for electrochemical carbon dioxide reduction reaction (CORR). This study synthesized various salts-TBA (tetra--butylammonium), Cs, Sr, and Ba-of a dipalladium-incorporated POM (Pd2, [γ-HSiWOPd(OAc)]) immobilized on a carbon support (Pd2/C).

A high-resolution structural characterization and physicochemical study of how a peptoid binds to an oncoprotein MDM2.

Peptoids are a promising drug modality targeting disease-related proteins, but how a peptoid engages in protein binding is poorly understood. This is primarily due to a lack of high-resolution peptoid-protein complex structures and systematic physicochemical studies. Here, we present the first crystal structure of a peptoid bound to a protein, providing high-resolution structural information about how a peptoid binds to a protein.

Supramolecular copolymerization of hydrophobic and hydrophilic monomers in liquid crystalline media.

In the case of covalent polymers, immiscible polymers can be integrated by covalently linking them together, but such a strategy is not possible in supramolecular polymers. Here we report the supramolecular copolymerization of two porphyrin-based monomers, P and P with side chains bearing cyanobiphenyl (CB) groups at the ends of hydrophobic alkyl or hydrophilic tetraethylene glycol chains, respectively. These monomers undergo self-sorting supramolecular polymerization in highly diluted solutions ([monomer] = 3.

Fluoroalkylated hypervalent sulfur fluorides: radical addition of arylchlorotetrafluoro-λ-sulfanes to tetrafluoroethylene.

Fluorinated groups are essential hydrophobic groups in drug design. Combining a carbon-free tetrafluoro-λ-sulfanyl (SF) group with a polyfluoroalkyl group (R) provides SFR groups, exhibiting high hydrophobicity with a short carbon chain. In this study, various aryltetrafluoro(polyfluoroalkyl)-λ-sulfanes (ArSFR) were synthesized through the radical addition of arylchlorotetrafluoro-λ-sulfanes (ArSFCl) to tetrafluoroethylene.

Organocatalyzed ring-opening reactions of γ-carbonyl-substituted ε-caprolactones.

Side-chain-functionalized aliphatic polyesters are promising as functional biodegradable polymers. We have investigated ring-opening reactions of γ-carbonyl-substituted ε-caprolactones (gCCLs) to obtain poly(ε-caprolactone) (PCL) analogues. Organic catalysts and Sn(Oct) often used for the ring-opening polymerization (ROP) of ε-caprolactone (CL) have been explored to find the conditions for the formation of polymeric products of gCCLs.

Hysteresis behavior in the unfolding/refolding processes of a protein trapped in metallo-cages.

Confinement of molecules in a synthetic host can physically isolate even their unstable temporary structures, which has potential for application to protein transient structure analysis. Here we report the NMR snapshot observation of protein unfolding and refolding processes by confining a target protein in a self-assembled coordination cage. With increasing acetonitrile content in CDCN/HO media (50 to 90 vol%), the folding structure of a protein sharply denatured at 83 vol%, clearly revealing the regions of initial unfolding.

Photocatalytic formation of a gas permeable layer selectively deposited on supported metal nanoparticles for sintering-resistant thermal catalysis.

Nanoparticle aggregation of supported metal catalysts at high temperatures is a serious problem that causes a drop in catalytic performance. This study investigates the protection of metal nanoparticles from sintering by selectively forming nanoscale SiO shells on Pd supported on TiO by ultraviolet (UV) light irradiation. The proton-coupled reduction reaction increases the local pH around Pd nanoparticles, resulting in hydrolysis of tetraethoxyorthosilicate (TEOS) in only the vicinity of the metal.

Label-free quantification of passive membrane permeability of cyclic peptides across lipid bilayers: penetration speed of cyclosporin A across lipid bilayers.

Cyclic peptides that passively penetrate cell membranes are under active investigation in drug discovery research. PAMPA (Parallel Artificial Membrane Permeability Assay) and Caco-2 assay are mainly used for permeability measurements in these studies. However, permeability rates across the artificial membrane and the cell monolayer used for these assays are intrinsically different from the ones across pure lipid bilayers.

Variable control of the electronic states of a silver nanocluster protonation/deprotonation of polyoxometalate ligands.

The properties of metal nanoclusters depend on both their structures and electronic states. However, in contrast to the significant advances achieved in the synthesis of structurally well-defined metal nanoclusters, systematic control of their electronic states is still challenging. In particular, stimuli-responsive and reversible control of the electronic states of metal nanoclusters is attractive from the viewpoint of their practical applications.

Tracking the crystallization behavior of high-silica FAU during AEI-type zeolite synthesis using acid treated FAU-type zeolite.

During AEI zeolite synthesis using acid treated FAU (AcT-FAU), we found the recrystallization of high-silica FAU with high crystallinity and Si/Al ratio of 6.1 using ,-dimethyl-3,5-dimethylpiperidinium hydroxide (DMDMPOH) after 2 h, followed by the crystallization of AEI FAU-to-AEI interzeolite conversion at a longer synthesis time. In order to understand the formation mechanism of high-silica FAU and generalize its direct synthesis, we have investigated this synthesis process.

The impact of surface Cu of ZnO/(Cu Zn )O heterostructured nanowires on the adsorption and chemical transformation of carbonyl compounds.

The surface cation composition of nanoscale metal oxides critically determines the properties of various functional chemical processes including inhomogeneous catalysts and molecular sensors. Here we employ a gradual modulation of cation composition on a ZnO/(Cu Zn )O heterostructured nanowire surface to study the effect of surface cation composition (Cu/Zn) on the adsorption and chemical transformation behaviors of volatile carbonyl compounds (nonanal: biomarker). Controlling cation diffusion at the ZnO(core)/CuO(shell) nanowire interface allows us to continuously manipulate the surface Cu/Zn ratio of ZnO/(Cu Zn )O heterostructured nanowires, while keeping the nanowire morphology.

Structural exploration of rhodium catalysts and their kinetic studies for efficient parahydrogen-induced polarization by side arm hydrogenation.

Parahydrogen-induced polarization (PHIP) is a rapid and cost-effective hyperpolarization technique using transition metal-catalysed hydrogenation with parahydrogen. We examined rhodium catalysts and their kinetic studies, rarely considered in the research of current PHIP. It emerged that rhodium complexes with electron-donating bisphosphine ligands, with a dicyclohexylphosphino group, appear to be more effective than conventional rhodium catalysts.

Targeted Therapy against Metastatic Melanoma Based on Self-Assembled Metal-Phenolic Nanocomplexes Comprised of Green Tea Catechin.

The targeted therapy of metastatic melanoma is an important yet challenging goal that has received only limited attention to date. Herein, green tea polyphenols, (-)-epigallocatechin-3-gallate (EGCG), and lanthanide metal ions (Sm) are used as building blocks to engineer self-assembled Sm-EGCG nanocomplexes with synergistically enhanced tumor inhibitory properties. These nanocomplexes have negligible systemic toxic effects on healthy cells but cause a significant reduction in the viability of melanoma cells by efficiently regulating their metabolic pathways.

Self-assembly of peptide amphiphiles by vapor pressure osmometry and dissipative particle dynamics.

Peptide amphiphiles are one of the most promising materials in the biomedical field, so much effort has been devoted to characterizing the mechanism of their self-assembly and thermosensitive gelation. In this work, vapor pressure osmometry measurements were carried out to parameterize the thermosensitivity of interactions between peptide amphiphiles in an aqueous solution. The osmometry measurement verified that the peptides became more hydrophobic as temperature increased, which was quantitatively described with the Flory-Huggins parameter.

Intercalation-controlled cyclodehydration of sorbitol in water over layered-niobium-molybdate solid acid.

Layered niobium molybdate (HNbMoO6 ) was used in the aqueous-phase dehydration of sorbitol and was found to exhibit remarkable selectivity toward its monomolecular-dehydrated intermediate 1,4-sorbitan. This was attributed to the selective intercalation of sorbitol within the interlayers with strong Brønsted acid sites.