Precise Size‐Selective Sieving of Nanoparticles Using a Highly Oriented Two‐Dimensional Supramolecular Polymer

The development of size‐selective membranes with well‐defined nanopores towards the precise separation of nanometer‐sized substances is a challenging task to achieve. Here a supramolecular membrane is presented that comprises a highly oriented, honeycomb‐like, 2D supramolecular polymer on a polycarbonate filter support. It enables precise size‐selective sieving of colloidal nanoparticles (NPs). Owing to the uniform parallel‐aligned nanocavities within the 2D supramolecular polymers, the composite membrane shows a high size‐selectivity with a sub‐nanometer accuracy in the cutoff size of about 4.0 nm. In principle, the species of size‐separable particles are unlimited, as demonstrated by quantum dots, noble metal, and metal oxide NPs. This supramolecular membrane combined with filtration advances the potential of NPs in terms of their monochromatic emission and size monodispersity, and also enables rapid removal of small magnetic NP adsorbents that are otherwise difficult to capture.     

Study of Blood Porphyrin Spectral Profile for Diagnosis of Chronic Renal Failure

The progression to end-stage renal failure is independent of the initial pathogenic mechanism. Metabolic acidosis is a common consequence of chronic renal failure that results from inadequate ammonium excretion and decreased tubular bicarbonate reabsorption. Protoporphyrin IX (PpIX) is the immediate metabolic precursor of the heme molecule. The purpose of this study was to evaluate the levels of erythrocytes protoporphyrin IX at an animal model during progressive renal disease. A total of 36 eight-week-old male Wistar rats were divided into six groups: Normal, 4 and 8 weeks after 5/6 nephrectomy (NX). Renal function was evaluated by creatinine clearance and plasma creatinine levels. The autofluorescence of erythrocytes porphyrin of healthy and NX rats was analyzed using fluorescence spectroscopy. Emission spectra were obtained by exciting the samples at 405 nm. Significant differences between normal and NX rats autofluorescence shape occurred in the 600–700 nm spectral region. A correlation was observed between emission band intensity at 635 nm and progression of renal disease.     

Synthesis of novel neuroexcitatory amino acids derived from kainic acid

The synthesis of the novel epimeric amino acids $\text{5a}$ and $\text{7a}$ by oxidation of methyl ketones derived from kainic acid is described. On biological testing both compounds exhibit a strong neuroexcitatory activity.     

In situ ultraviolet Raman spectroscopy of the reduction of chromia on alumina catalysts

A fluidized bed in situ cell is used to examine the chromia on alumina catalyst surface. The loading is varied from 1 to 20% chromium oxide on alumina. The structure of the surface is monitored as a function of temperature, reduction, and hydration. This is the first study to use ultraviolet excitation to study a reduced chromium catalyst surface. Reduction of the sample in hydrogen gas leads to the formation of noncrystalline Cr(3+) species. Addition of potassium to the surface reduces the size of the chromia clusters.     

Syntheses, structural characterization, and host-guest chemistry of ethynylcrown ether containing polynuclear gold(I) complexes

Two novel ethynylcrown ether containing di- and tetranuclear gold(I) complexes have been synthesized and structurally characterized; their binding ability toward various metal ions has also been studied.     

Syntheses and photochromic studies of dithienylethene-containing imidazolium derivatives and their reactivity towards nucleophiles

A series of dithienylethene-containing imidazolium salts with various substituents on the 2-position of the imidazolium ring has been synthesized. The photochromic properties of these compounds have been studied, and the closed forms are found to be solvatochromic due to the donor-acceptor interaction with the solvent molecules. The closed form of the imidazolium salt shows a much higher affinity towards nucleophiles over the open form of the salt. A reaction pathway has been proposed to account for this reactivity difference based on the structure-property relationship, and the possible structure of the reaction product is discussed.     

Syntheses and Photophysical Properties of N‐Pyridylimidazol‐2‐ylidene Tetracyanoruthenates(II) and Photochromic Studies of Their Dithienylethene‐Containing Derivatives

A series of tetracyanoruthenate(II) with chelating pyridyl N‐heterocyclic carbene ligands (NHC‐py) was synthesized and characterized. Their photophysical and electrochemical properties as well as the photochromic behavior of their dithienylethene‐containing complexes were studied. Photocyclization was found to take place upon irradiation into the metal‐to‐ligand charge transfer (MLCT) absorption bands of these complexes, and evidence is provided to support the triplet‐sensitizing reaction pathway.