Analysis of cancer cell lipids using matrix‐assisted laser desorption/ionization 15‐T Fourier transform ion cyclotron resonance mass spectrometry

A combination of methodologies using the extremely high mass accuracy and resolution of 15‐T Fourier transform ion cyclotron resonance (FT‐ICR) mass spectrometry (MS) was introduced for the identification of intact cancer cell phospholipids. Lipids from a malignant glioma cell line were initially analyzed at a resolution of >200 000 and identified by setting the mass tolerance to ±1 mDa using matrix‐assisted laser desorption/ionization (MALDI) 15‐T FT‐ICR MS in positive ion mode. In most cases, a database search of potential lipid candidates using the exact masses of the lipids yielded only one possible chemical composition. Extremely high mass accuracy (<0.1 ppm) was then attained by using previously identified lipids as internal standards. This, combined with an extremely high resolution (>800 000), yielded well‐resolved isotopic fine structures allowing for the identification of lipids by MALDI 15‐T FT‐ICR MS without using tandem mass spectrometric (MS/MS) analysis. Using this method, a total of 38 unique lipids were successfully identified. Copyright © 2012 John Wiley & Sons, Ltd.     

Coherence three-dimensional imaging spectrometry based on measurement of rotated-hyperbolic volume interferograms

A new interferometric technique to obtain three-dimensional multispectral images of spatially incoherent polychromatic-source distributions is investigated. This technique is based on the measurement of a new type of volume interferogram, herein called the rotated-hyperbolic volume interferogram, which can be obtained by existing interferometer together with a novel aperture synthesis. This paper reports the first demonstration of the method: measurement of a monochromatic point source. The results obtained from this measurement included three-dimensional spatial information and spectral information corresponding to the impulse response function defined over a four-dimensional space. These experimental results confirmed that the imaging characteristics, particularly depth resolution, of the new method are superior to those of previous methods.     

Synthesis of carbon encapsulated metal (Ni and Cu) nano particles and applications for chiral catalysts

Research on Chemical Intermediates - Carbon-encapsulated Ni and Cu nanoparticles with a core/shell structure were synthesized by levitational gas condensation (LGC). Methane (CH4) gas was used to...     

Proton-conducting composite membranes from graft copolymer electrolytes and phosphotungstic acid for fuel cells

New organic–inorganic composite membranes based on poly(vinylidene fluoride-co-chlorotrifluoroethylene)-graft-poly(styrene sulfonic acid) [P(VDF-co-CTFE)-g-PSSA] with embedded phosphotungstic acid (PWA) were prepared. Fourier transform infrared spectra indicated the existence of a specific interaction between P(VDF-co-CTFE)-g-PSSA graft copolymer and PWA particles. PWA nanoparticles were well confined in the polymeric matrix up to 20 wt.%, above which they started to be extracted from the matrix, as revealed by scanning electron microscope analysis. Accordingly, Young’s modulus of membranes also increased with PWA concentration up to 20 wt.%, above which it continuously decreased. Upon incorporation of PWA nanoparticles, the proton conductivity of composite membranes slightly decreased from 0.042 to 0.035 S/cm at room temperature up to 20 wt.%, presumably due to strong interaction between the sulfonic acids of graft copolymer and PWA nanoparticles. The characterization by thermal gravimetric analysis demonstrated the enhancement of thermal stabilities of the composite membranes with increasing concentration of PWA.     

Synthesis and characterization of low‐bandgap cyclopentadithiophene‐biselenophene copolymer and its use in field‐effect transistor and polymer solar cells

Novel series of conjugated copolymers, incorporating cyclopentadithiophene (CPDT) and the biselenophene ( R‐CPDT‐Se2 ), were synthesized by Pd‐catalyzed Stille coupling polymerization. The optical, electrochemical, field‐effect carrier mobilities, and photovoltaic properties of the R‐CPDT‐Se2 were investigated and compared with cyclopentadithiophene (CPDT) and the bithiophene ( EHex‐CPDT‐T2 ). The highest hole mobility of thin film transistor devices fabricated with new p‐type polymer semiconductors, Oct‐CPDT‐Se2 , was 1.3 × 10^?3 cm²/Vs with an on/off ratio of about 10⁵. The maximum power conversion efficiency of polymer solar cell fabricated with the blend of EHex‐CPDT‐Se2 /C₇₁‐PCBM reached 1.86% with an open circuit voltage (V_OC) of 0.55 V, a short circuit current density (J_sc) of 7.27 mA/cm², and a fill factor (FF) of 0.47 under AM 1.5G irradiation (100 mW/cm²). © 2009 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2009     

Polyurea-reinforced polyacrylonitrile

Polyacrylonitrile (PAN) fibers were reinforced with three different types of polyurea (PU), which were synthesized in the presence of PAN dissolved in dimethyl formamide (DMF) (referred to as an in situ blend). Solution viscosity increased with increasing PU content, with viscosity yield seen at high PU content and an extended Newtonian plateau at low PU content. The reinforcing effect was greater with linear PUs, among which PU prepared from toluene diisocyanate (TDI) and ethylene diamine (EDA) gave the greatest improvement.     

In vitro skin permeation of cubosomes containing water soluble extracts of Korean barberry

The monoolein (MO) cubic phases containing water soluble extract (WSE) from Berberis koreana (Korean barberry) were prepared by hydrating the molten MO with aqueous solutions of WSE (0.5, 1.0, and 1.5%). The phase transition temperature of cubic phase containing WSE (∼70°C) was almost the same as that of WSE-free MO cubic phase that indicates that WSE was immobilized in the water channels of the cubic phase and did not affect its structure. The release of WSE from the cubic phase fits the first order process. The cubosomes were obtained by micronizing the cubic phase in a sonicator using Pluronic F127 as a dispersant. The cubosomes were stable in size at the ethanol concentration ≲16%. When compared with WSE solution in phosphate-buffered saline (10 mM, pH 7.4), in vitro skin permeation of WSE in the cubosomes was enhanced by about two times.