Determination of concentration and enantiomeric excess of amines and amino alcohols with a chiral nickel(II) complex

A chiral N,N'-dioxide-Ni(II) complex was found to exhibit highly enantioselective fluorescent recognition of chiral amines and amino alcohols. It can be used to determine their concentration and ee value. Using a 96-well plate, high-throughput screening for enantiomer discrimination was accomplished.     

Electrokinetically-controlled RNA-DNA hybridization assay for foodborne pathogens

Chitosan microspheres were prepared by an emulsion crosslinking method using glutaraldehyde as the cross-linker. Two auxins were dissolved in ethyl benzoate and encapsulated into the microspheres. The best encapsulation efficiency for naphthalene-1-acetic acid and indole-3-acetic acid, respectively, are 68% and 56% and depends on the selection of the appropriate extent of crosslinker, crosslinking time, and the ratio of the oil/water phase. The microspheres were characterized by FTIR spectroscopy. Differential scanning calorimetry was applied to study the thermal stabilities, and scanning electron microscopy to investigate the morphology of the loaded microspheres. In-vitro release studies performed in buffered aqueous methanol at pH 7.4 indicated that the cumulative release rate of the auxins from the particles reaches a maximum (60%) after about 120?h. The release rate in water is higher than the one in methanol. Based on data for the correlation coefficient it is concluded that the drug release is controlled by a diffusion mechanism that follows a super Case-II transport scheme.

Design, synthesis and antifibrotic activities of carbohydrate-modified 1-(substituted aryl)-5-trifluoromethyl-2(1H) pyridones

Pirfenidone, a pyridone compound, is an effective and novel antifibrotic agent. In this article, we describe the design, synthesis and activity evaluation of novel antifibrotic agents, 1-(substituted aryl)-5-trifluoromethyl-2(1H) pyridones modified with carbohydrate. Most of the title compounds exhibited comparable or better inhibitory activity than fluorofenidone. Notably, compound 19a demonstrated the highest cell-based inhibitory activity against NIH 3T3 (IC(50) = 0.17 mM).     

Myoglobin-directed assemblies of binary monolayers functionalized with iminodiacetic acid ligands at the air-water interface through metal coordination for multivalent protein binding

Myoglobin binding to the binary monolayers composed of sodium hexadecylimino diacetate and hexadecanol at the air-water interface by means of metal coordination has been investigated using infrared reflection absorption spectroscopy (IRRAS). In the absence of Cu(2+), no myoglobin binding to the binary monolayers was observed. In the presence of Cu(2+), remarkable myoglobin binding to the binary monolayers resulted from the formation of ternary complexes of iminodiacetate (IDA)-Cu(2+)-surface histidine. Myoglobin-directed assemblies of the binary monolayers facilitated multivalent protein binding through lateral rearrangements of the IDA ligands and reorientations of the alkyl chains for enhanced protein binding. Myoglobin binding to and desorption from the binary monolayers could be readily controlled through metal coordination.     

Two new lupene-type triterpenoids from the roots of Liquidambar formosana

Two new lupene-type triterpenoids, 3β,6β-dihydroxylup-20(29)-en-28-oic acid β-glucopyranosyl ester (1) and 2α-acetoxyl-3β,6β-dihydroxylup-20(29)-en-28-oic acid β-glucopyranosyl ester (2), along with 18 known compounds, were isolated from Liquidambar formosana. The structures were elucidated on the basis of spectroscopic methods, including UV, IR, ESIMS, 1D- and 2D-NMR experiments, as well as by comparison of the spectral data with those of related compounds.     

Protein-assisted synthesis of double-shelled CaCO3 microcapsules and their mineralization with heavy metal ions

Calcium carbonate (CaCO(3)) is one of the most abundant and important biominerals in nature. Due to its biocompatibility, biodegradability and nontoxicity, CaCO(3) has been investigated extensively in recent years for various fundamental properties and technological applications. Inspired by basic wall structures of cells, we report a protein-assisted approach to synthesize CaCO(3) into a double-shelled structural configuration. Due to varying reactivities of outer and inner shells, the CaCO(3) microcapsules exhibit different sorption capacities and various resultant structures toward different kinds of heavy metal ions, analogical to biologically controlled mineralization (BCM) processes. Surprisingly, three mineralization modes resembling those found in BCM were found with these bacterium-like "CaCO(3) cells". Our investigation of the cytotoxicity (MTT assay protocol) also indicates that the CaCO(3) microcapsules have almost no cytotoxicity against HepG2 cells, and they might be useful for future application of detoxifying heavy metal ions after further study.