Raman dye-labeled nanoparticle probes for proteins

In this paper, we demonstrate how one can chemically design Raman dye-functionalized nanoparticle probes with specific protein-binding affinities and use these probes, coupled with surface-enhanced Raman scattering (SERS) spectroscopy, to perform multiplexed screening of protein-small molecule interactions and protein-protein interactions in a protein microarray format.     

Preparation and Radical Oligomerization of anFe(II) Complex without Loss of Spin-Crossover Properties

 11-(4H-1,2,4-Triazol-4-yl)-undecylmethacrylate (1), a new ligand for Fe(II) spin-crossover (SCO) complexes containing a polymerizable group, was synthesized and characterized. The complex [Fe·1 ₃](BF₄)₂ (2) was obtained by reaction of 1 with Fe(BF₄)₂·6H₂O (molar ratio 1/Fe(II) = 3/1) in THF. Complex 2 showed a gradual spin-crossover between 80 and 230 K. The methacrylate units in the ligands of complex 2 could be oligomerized radically in solution (initiator: azoisobutyronitrile) without loss of the spin-crossover behaviour.     

The transformation operator for Schrödinger operators on almost periodic infinite-gap backgrounds

We investigate the kernels of the transformation operators for one-dimensional Schrödinger operators with potentials, which are asymptotically close to Bohr almost periodic infinite-gap potentials.     

Model reduction and clustering techniques for crash simulations

Model reduction in car crash simulations is a fairly new research field. In this paper, a possible workflow is presented: Since nonlinear behavior can occur, parts with linear and nonlinear behavior need to be separated with clustering methods such as k-means or spectral clustering. For the latter, a nonlinear reduction technique such as POD-DEIM needs to be applied. A longitudinal chassis beam of a 2001 Ford Taurus is used to examine the different clustering methods. (© 2015 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim)     

High-yield synthesis of pure ZnO nanoparticles by one-step solid-state reaction approach for enhanced photocatalytic activity

Zinc oxide (ZnO) nanostructures were synthesized via a one-step solid-state reaction approach in ammonia (NH₃) gas environment with different temperature ramp rates. The so-formed nanostructures were characterized using X-ray diffraction (XRD) for phase identification, where the typical wurtzite hexagonal structure was observed. Scanning electron microscopy (SEM) confirmed the particle size to be in the range 45–50 nm, the same as calculated by the XRD pattern for the ramp rate of 10 °C/min. Energy dispersive X-ray (EDX) spectroscopy and X-ray photoelectron spectroscopy (XPS) confirmed the chemical purity of the samples. The photoluminescence (PL) spectrum indicated multiple near-band-edge emissions and energy-band emissions. Then, these ZnO nanomaterials were used for the degradation of crystal violet (CV) dye under UV light irradiation. The CV solution was completely degraded in 2 hr. The initial photocatalyst and dye amounts of 0.2 g/100 ml and 0.5 mg/L, respectively, were found to be the optimum values for maximum degradation efficiency. The ZnO-based photocatalyst was stable up to three cycles of reuse. These results indicate that the high surface area and porosity of the nanomaterials are responsible for the high efficiency, which was confirmed by specific surface area analysis.     

Nigella sativa extract as a potent antioxidant for petrochemical-induced oxidative stress

Various beneficial properties has been attributed to Nigella sativa, including its antioxidant potential. Previously, it was reported that supercritical fluid extraction (SFE) could be used to obtain N. sativa extract rich in antioxidants. In the present study, N. sativa extracts prepared using the previously optimized SFE as well as the traditional Soxhlet extraction approaches were analyzed for various known antioxidants. N. sativa extracts were found to prevent protein carbonyl formation as well as depletion of intracellular glutathione (GSH) in fibroblasts exposed to toluene. Furthermore, partially purified SFE and Soxhlet fractions could prevent loss of hepatic GSH in toluene-induced oxidative stressed Wistar rats as well as in L929 fibroblasts. The results showed that SFE-produced N. sativa extract is richer in antioxidants than the Soxhlet approach. It was also shown using preparative silica gel and reverse phase chromatography that different fractions of SFE-extracted or Soxhlet-extracted N. sativa had different levels of protective effects with regards to GSH depletion in vivo as well as in cell culture. Although fractions rich in thymoquinone were found to be most potent in terms of antioxidant capacity, the data indicates that the protective effects of N. sativa may not only be due to thymoquinone, but perhaps other antioxidants.     

Phytochemical analysis and Enzyme Inhibition Assay of Aerva javanica for Ulcer

ABSTRACT: BACKGROUND: Aerva javanica (Burm. f.) Juss. ex Schult. (Amaranthacea) is traditionally used for the treatment of wound healings, cough, diarrhoea, ulcer and hyperglycaemia. The current study was aimed to fractionate and isolate bioactive compounds and ultimately to evaluate their anti-ulcereogenic potential. RESULTS: In order to achieve these aims, the fractionation, purifications and then biological potential determination of the isolated compounds was carried out. For purification purpose, initially extraction of the plant material was done with aqueous MeOH in the order of increasing polarity by using solvent-solvent extraction method. Phytochemical analysis revealed the presence of three compounds, 3-hydroxy-4 methoxybenzaldehyde (1), ursolic acid (2) and (E)-N-(4-hydroxy-3-methoxyphenethyl)-3-(4-hydroxy-3-ethoxyphenyl) acryl amide (3). Inhibition of urease activity of various fractions revealed that ethyl acetate fraction showed significant activity (P <0.05) as compared to other fractions. (E)-N-(4-hydroxy-3- methoxyphenethyl)-3-(4-hydroxy-3-ethoxyphenyl) acryl amide (3) showed marked anti ulcer activity (P <0.05). CONCLUSION: These results suggested the mild potential of A. javanica against ulcer.