Effects of gamma irradiation on the yields of volatile extracts of Angelica gigas Nakai

The study was carried out to determine the effects of gamma irradiation on the volatile flavor components including essential oils, of Angelica gigas Nakai. The volatile organic compounds from non- and irradiated A. gigas Nakai at doses of 1, 3, 5, 10 and 20 kGy were extracted by a simultaneous steam distillation and extraction (SDE) method and identified by GC/MS analysis. A total of 116 compounds were identified and quantified from non- and irradiated A. gigas Nakai. The major volatile compounds were identified 2,4,6-trimethyl heptane, α-pinene, camphene, α-limonene, β-eudesmol, α-murrolene and sphatulenol. Among these compounds, the amount of essential oils in non-irradiated sample were 77.13%, and the irradiated samples at doses of 1, 3, 5, 10 and 20 kGy were 84.98%, 83.70%, 83.94%, 82.84% and 82.58%, respectively. Oxygenated terpenes such as β-eudesmol, α-eudesmol, and verbenone were increased after irradiation but did not correlate with the irradiation dose. The yields of active substances such as essential oil were increased after irradiation; however, the yields of essential oils and the irradiation dose were not correlated. Thus, the profile of composition volatiles of A. gigas Nakai did not change with irradiation.     

Synthesis of a Polymer-bound Sensitizer and its Application in the Photoisomerization of trans-Vitamin D_3 to cis-Vitamin D_3

The photochemistry of the vitamin D family and their precursors has been the subject of extensive studies for many years1-4. Most of the studies focus on the photoisomer- ization of 7-dehydrocholesterol and that of tachysterol to previtamin D3, which is of commercial importance in the synthesis of vitamin D34, 5. Recently the cis/trans isomerization of vitamin D analogs (Scheme 1) draws attention because of its importance in the synthesis of hydroxylated vitamin D metabolites6. However, o…     

Development of a competitive liposome-based lateral flow assay for the rapid detection of the allergenic peanut protein Ara h1

A competitive lateral flow assay for detecting the major peanut allergen, Ara h1, has been developed. The detector reagents are Ara h1-tagged liposomes, and the capture reagents are anti-Ara h1 polyclonal antibodies. Two types of rabbit polyclonal antibodies were raised either against the entire Ara h1 molecules (anti-Ara h1 Ab) or against an immunodominant epitope on Ara h1 (anti-peptide Ab). All of them reacted specifically with Ara h1 in Western Blot against crude peanut proteins. Moreover, the anti-Ara h1 Ab was chosen for this assay development because of its highest immunoactivity to Ara h1-tagged liposomes in the lateral flow assay. The calculated limit of detection (LOD) of this assay is 0.45 g mL^–1 of Ara h1 with a dynamic range between 0.1 and 10 g mL^–1 of Ara h1 in buffer. Additionally, the visually determined detection range is from 1 to 10 g mL^–1 of Ara h1 in buffer. Results using this assay can be obtained within 30 min without the need of sophisticated equipment or techniques; therefore, this lateral flow assay has the potential to be a cost-effective, fast, simple, and sensitive method for on-site screening of peanut allergens.     

Syntheses, structures, and magnetic properties of unusual nonlinear polynuclear copper(II) complexes containing derivatives of 1,2,4-triazole and pivalate ligands

Novel polynuclear Cu(II) complexes containing derivatives of 1,2,4-trizaole and pivalate ligands, [Cu(3)(mu(3)-OH)(mu-adetrz)(2)(piv)(5)(H(2)O)].6.5H(2)O (1) (adetrz = 4-amino-3,5-diethyl-1,2,4-triazole, piv = pivalate), [Cu(4)(mu(3)-OH)(2)(mu-atrz)(2)(mu-piv)(4)(piv)(2)].2MeOH.H(2)O (2) (atrz = 4-amino-1,2,4-triazole), [Cu(4)(mu(3)-OH)(2)(mu-tbtrz)(2)(mu-piv)(2)(piv)(4)].4H(2)O (3) (tbtrz = 4-tert-butyl-1,2,4-trizaole), and [Cu(4)(mu(3)-O)(2)(mu-admtrz)(4)(admtrz)(2)(mu-piv)(2)(piv)(2)].2[Cu(2)(mu-H(2)O)(mu-admtrz)(piv)(4)].13H(2)O [4 = 4a.2(4b).13H(2)O; admtrz = 4-amino-3,5-dimethyl-1,2,4-triazole], have been prepared and structurally characterized. 1 is an asymmetrical triangular complex containing a [Cu(3)(mu(3)-OH)] core with two Cu---Cu edges spanned by bridging adetrz ligands. 2, 3, and 4a are novel tetranuclear compounds containing a [Cu(4)(mu(3)-O)(2)] or [Cu(4)(mu(3)-OH)(2)] core with Cu---Cu edges spanned by bridging 1,2,4-triazole or pivalate ligands. 4b is a dinuclear compound with one admtrz and one water bridge, and it is the first dinuclear Cu(II) triazole complex with one bridging water molecule. 1 is one of few reported triangular Cu(II) complexes with derivatives of 1,2,4-triazole, while 2, 3, and 4a are the first group of the nonlinear tetranuclear Cu(II) compounds with derivatives of 1,2,4-triazole. Variable-temperature magnetic susceptibility studies on the powder samples of 1-3 reveal the overall antiferromagnetic coupling between Cu(II) ions with J values of -55.6 to -12.8 cm(-1) (1), -216.4 to 0 cm(-1) (2), and -259.8 to 4.8 cm(-1) (3).     

Two-particle friction in a mesoscopic solvent

The effects of hydrodynamic interactions on the friction tensors for two particles in solution are studied. The particles have linear dimensions on nanometer scales and are either simple spherical particles interacting with the solvent through repulsive Lennard-Jones forces or are composite cluster particles whose atomic components interact with the solvent through repulsive Lennard-Jones forces. The solvent dynamics is modeled at a mesoscopic level through multiparticle collisions that conserve mass, momentum, and energy. The dependence of the two-particle relative friction tensors on the interparticle separation indicates the importance of hydrodynamic interactions for these nanoparticles.     

Preparation and characterization of lithium ion-conducting glass-ceramics in the Li1 + xCrxGe2 − x(PO4)3 system

Li₂O–Cr₂O₃–GeO₂–P₂O₅ based glasses were synthesized by a conventional melt-quenching method and successfully converted into glass-ceramics through heat treatment. Experimental results of DTA, XRD, ac impedance techniques and FESEM indicated that Li_1.4Cr_0.4Ge_1.6(PO₄)₃ glass-ceramics treated at 900 °C for 12 h in the Li_1 + xCr_xGe_2 − x(PO₄)₃ (x = 0–0.8) system exhibited the best glass stability against crystallization and the highest ambient conductivity value of 6.81 × 10⁻⁴ S/cm with an activation energy as low as 26.9 kJ/mol. In addition, the Li_1.4Cr_0.4Ge_1.6(PO₄)₃ glass-ceramics displayed good chemical stability against lithium metal at room temperature. The good thermal and chemical stability, excellent conducting property, easy preparation and low cost make it promising to be used as solid-state electrolytes for all-solid-state lithium batteries.     

A Novel 3‐D Heterobimetallic Cyano‐bridged Coordination Polymer Incorporating Ag···Ag Interaction: [Cu(dien)Ag(CN)2]2[Ag2(CN)3][Ag(CN)2]

A three‐dimensional cyano‐bridged copper(II) complex, [Cu(dien)Ag(CN)₂]₂[Ag₂(CN)₃][Ag(CN)₂] ( 1 ) (dien = diethylenetriamine), has been prepared and characterized by X‐ray crystallography. Complex 1 crystallized in the monoclinic space group P2₁/n with a = 6.988(2), b = 17.615(6), c = 12.564(4) Å, β = 90.790(5)°. The crystal consists of cis‐[Cu(dien)]²⁺ units bridged by [Ag(CN)₂]^— to form a zig‐zag chain. The Ag atoms of the free and bridging [Ag(CN)₂]^— link together to form additional infinite zig‐zag chains with short Ag···Ag distances. The presence of Ag···Ag interactions effectively increases the dimensionality from a 1‐D chain to a 3‐D coordination polymer.     

Towards Single-component Molecular Conductor [Ni(dmit)_2] by Charge Disproportionation:2[Ni(dmit)_2]~(-0.5)[Ni(dmit)_2]+[Ni(dmit)_2]~-

It was commonly thought that a molecular conductor or semiconductor should be composed of at least two components to make the conducting component in partially charged state. However, this idea became questionable by the recent report of the single-component molecular conductor [Ni(tmdt)2]1 as well as several reports about single-component molecular semiconductors such as [Ni(ptdt)2]2 and [Ni(C10H10S8)2]3. In fact, as early as 1985, [Ni(dmit)2] as a by-product in synthesizing TTF[Ni(dmit…     

A Novel Fluorescent Aminoacid Designed for Fluorometric Detection of Cu （Ⅱ）

A fluorescent aminoacid was designed for selective and sensitive detection of Cu(II) in aqueous solution. The designing of this Cu(II) fluorescent chemosensing molecule, N ± (1‐naphthyl). aminoacetic acid (NAA), was based on the binding of Cu(II) to aminoacetic acid and the novel charge transfer photophysics of 1‐aminonaphthalenes. The fluorescence of NAA was found quenched by Cu (II) and several other metal ions of similar electronic structure such as Co(II), Ni(II) and Zn(II). The quenching was shown to occur via electron transfer within the metal‐NAA complex, which required an optimal combination of high binding affinity and favorable redox properties of the components in the metal‐NAA complex and hence afforded selective fluorometric detection of Cu(II). The calibration graph obeyed Stern‐Volmer theory and was shown for Cu(II) over the range of 0–2.75 ± 10–⁴ mol/L. The quenching constant of Cu(II) was measured as 8.0 ± 10³ mol/L that was two orders of magnitude higher than those of Co(II), Ni(II) and Zn(II). The 3SD limit of detection for Cu(II) was 8.00 ± 10^?6 mol/L with a coefficient of variation of 1.65%. Linear range for quantitative detection of Cu(II) was 2.67 ± 10^?5‐2.75 ± 10^?4 mol/L. The method was applied to synthetic sample measurements which gave recoveries of 105%‐112%.     

Ratiometric chemosensing of Mg ions by a calix[4]arene diamide derivative

A new chemosensor with a phenanthroimidazole subunit based upon calix[4]arene-diamide has been synthesized, and its Mg²⁺-selective fluoroionophoric properties were investigated in an aqueous DMSO solution. The compound exhibited a pronounced Mg²⁺-selective fluoroionophoric behavior over other physiologically relevant metal ions. A significant red shift in fluorescence emission (Δλ = 86 nm) provided the ratiometric determination as well as naked-eye detection of Mg²⁺ ions.