Determination of Ethopabate Residues in Chicken Muscles, Liver, and Eggs after Aqueous SDS Extraction by Micellar Liquid Chromatography with Fluorescence Detection with Application to Baby Food

A simple and sensitive liquid chromatographic method was optimized and validated for the analysis of ethopabate residues in chicken muscles, liver, and eggs. Aqueous sodium dodecyl sulfate (SDS) solution was used for extraction. Analytical separation was performed in less than 8 min using a C18 column (150?×?4.6 mm internal diameter, 5 μm particle size) with fluorescence detection at 271/364 nm. A micellar solution composed of 0.1 M SDS, 10 % 1-propanol, and 0.3 % triethylamine in 0.02 M phosphoric acid adjusted to pH?4 was used as the mobile phase. The method was fully validated in accordance with International Conference on Harmonization guidelines. The micellar method was successfully applied to quantitatively determine ethopabate residues in spiked chicken muscles, liver, and eggs. It was also extended to the determination of ethopabate residues in chicken-based baby food. The recoveries obtained were in the 93.81–115.67 % range. The limit of detection was found to be 1.6 ng/g. High extraction efficiency for ethopabate was obtained without matrix interference and in the subsequent chromatographic determination. No organic solvent was used during the pretreatment step.     

Tuning the Stability of Graphene Layers by Phthalocyanine‐Based oPPV Oligomers Towards Photo‐ and Redoxactive Materials

In contrast to pristine zinc phthalocyanine (1), zinc phthalocyanine based oPPV‐oligomers (2–4) of different chain lengths interact tightly and reversibly with graphite, affording stable and finely dispersed suspensions of mono‐ to few‐layer graphene—nanographene (NG)—that are photoactive. The p‐type character of the oPPV backbones and the increasing length of the oPPV backbones facilitate the overall π–π interactions with the graphene layers. In NG/2, NG/3, and NG/4 hybrids, strong electronic coupling between the individual components gives rise to charge transfer from the photoexcited zinc phthalocyanines to NG to form hundreds of picoseconds lived charge transfer states. The resulting features, namely photo‐ and redoxactivity, serve as incentives to construct and to test novel solar cells. Solar cells made out of NG/4 feature stable and repeatable photocurrent generation during several ‘on‐off’ cycles of illumination with monochromatic IPCE values of around 1%.     

High concentrations of essential and toxic elements in infant formula and infant foods – A matter of concern

This study assessed concentrations in and intake of toxic and essential elements from formulas and foods intended for infants during their first 6 months of life. Concentrations of the essential elements Ca, Fe, Zn, Mn and Mo were significantly higher in most formulas than in breast milk. Daily intake of Mn from formula varies from ten up to several hundred times the intake of the breast fed infant, levels that may be associated with adverse health effects. One portion of infant food provided significantly more Fe, Mn, Mo, As, Cd, Pb and U than one feeding of breast milk, but less Ca, Cu and Se. Rice-based products in particular contained elevated As concentrations. Drinking water used to mix powdered formula may add significantly to the concentrations in the ready-made products. Evaluation of potentially adverse effects of the elevated element concentrations in infant formulas and foods are warranted.     

Microencapsulation of Fish Oil by Spray Granulation and Fluid Bed Film Coating

Abstract: The stability of microencapsulated fish oil prepared with 2 production processes, spray granulation (SG) and SG followed by film coating (SG-FC) using a fluid bed equipment, was investigated. In the 1st process, 3 types of fish oil used were based on the ratios of eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) (10/50, 33/22, and 18/12). Each type was emulsified with soluble soybean polysaccharide (SSPS) and maltodextrin to produce 25% oil powders. In the 2nd process, 15% film coating of hydroxypropyl betacyclodextrin (HPBCD) was applied to the granules from the 1st process. The powder stability against oxidation was examined by measurement of peroxide values (PV) and headspace propanal after storage at room temperature and at 3 to 4 °C for 6 wk. Uncoated powder containing the lowest concentration of PUFA (18/12) was found to be stable during storage at room temperature with maximum PV of 3.98 ± 0.001 meq/kg oil. The PV increased sharply for uncoated powder with higher concentration of omega-3 (in 33/22 and 10/50 fish oils) after 3 wk storage. The PVs were in agreement with the concentration of propanal, and these 2 parameters remained constant for most of the uncoated powders stored at low temperature. Unexpectedly, the outcomes showed that the coated powders had lower stability than uncoated powders as indicated by higher initial PVs; more hydroperoxides were detected as well as increasing propanal concentration. The investigation suggests that the film-coating by HPBCD ineffectively protected fish oil as the coating process might have induced further oxidation; however, SG is a good method for producing fish oil powder and to protect it from oxidation because of the “onion skin” structure of granules produced in this process.     

Vacuum packed particles as flexible endoscope guides with controllable rigidity

In order to fully benefit from the functionalities of flexible endoscopes in surgery a simple shaft-guide that can be used to support the flexible endoscope shaft is required. Such a shaft-guide must be flexible during insertion into the human body and rigidified when properly positioned to support the flexible endoscope shaft. A shaft-guide called ‘Vacu-SL’ was designed, consisting of a foil tube, filled with particles, that is rigidified by creating a vacuum in its tube. It is expected that the bending stiffness of a loaded, rigidified Vacu-SL shaft-guide is significantly influenced by the shape, hardness and size of the filler particles used. The goal of this study was to find the relations between the filler particles’ size, shape and hardness and a rigidified Vacu-SL shaft-guide’s bending stiffness. Vacu-SL test models were made using polystyrene, acrylic glass, glass, steel, and corundum particles as spheres, pebbles and granulate, with average diameters between 0.16–1.7 mm. These test models were rigidified and then loaded in a tensile tester. The forces needed for 5 and 10 mm deflections of the rigidified test models were measured. The results show that particle size, shape and hardness all influence a rigidified Vacu-SL shaft-guide’s bending stiffness. Size and hardness showed an optimum and granules performed better than spheres. Although the maximally measured bending stiffness might be insufficient to enable proper guidance of flexible endoscope shafts, the results suggest several ways to successfully improve the Vacu-SL shaft-guide.     

Preparation and characterization of poly(lactic‐co‐glycolic acid) microparticles containing DNA molecules encoding a malaria vaccine candidate

BACKGROUND: A novel ultrasonic atomization approach for the formulation of biodegradable poly(lactic‐co‐glycolic acid) (PLGA) microparticles of a malaria DNA vaccine is presented. A 40 kHz ultrasonic atomization device was used to create the microparticles from a feedstock containing 5 volumes of 0.5% w/v PLGA in acetone and 1 volume of condensed DNA which was fed at a flow rate of 18 ml h^?1. The plasmid DNA vectors encoding a malaria protein were condensed with a cationic polymer before atomization. RESULTS: High levels of gene expression in vitro were observed in COS‐7 cells transfected with condensed DNA at a nitrogen to phosphate (N/P) ratio of 10. At this N/P ratio, the condensed DNA exhibited a monodispersed nanoparticle size (Z‐average diameter of 60.8 nm) and a highly positive zeta potential of 38.8 mV. The microparticle formulations of malaria DNA vaccine were quality assessed and it was shown that the microparticles displayed high encapsulation efficiencies between 82–96% and a narrow size distribution in the range of 0.8–1.9 µm. In vitro release profile revealed that approximately 82% of the DNA was released within 30 days via a predominantly diffusion controlled mass transfer system. CONCLUSIONS: This ultrasonic atomization technique showed excellent particle size reproducibility and displayed potential as an industrially viable approach for the formulation of controlled release particles. Copyright © 2009 Society of Chemical Industry     

Discharge rate capabilities of alkaline AgCuO2 electrode

A series of AgCuO₂ samples are prepared and tested as alkaline cathode materials for primary batteries. AgCuO₂ discharges via four equivalent-charge reduction processes, the rate capabilities of which are determined. At ambient temperature AgCuO₂ displays superior rate capabilities for the two highest voltage processes. For all samples, the rate capability of the two lower voltage processes is always superior to those at higher voltage. This is due to the electrode intrinsically doping itself with elemental silver during discharge as part of the second reduction process. The electrode compares favourably with commercial electrolytic manganese dioxide but is prone to self-discharge, the kinetics of which are also discussed.     

New developments in Cu(In,Ga)(S, Se)2 thin film modules formed by rapid thermal processing of stacked elemental layers

A second-generation process for high-efficiency large-area Cu(In,Ga)(Se,S)₂ thin film (CIGSSe) solar modules has been developed applying controlled sodium doping and rapid thermal processing for absorber formation. The pilot line delivers aperture area efficiencies of 12.2%±0.5% (average) for 30×30 cm² modules and a certified champion efficiency of 13.1% for an unencapsulated 60×90 cm² demonstrator module. The stability of the frameless pilot line modules with a low-cost package against humidity is confirmed externally by passing the damp heat test sequence according to IEC 61646. Substitution of CBD-CdS by CBD-Zn(S, OH) buffer layers yields efficiencies up to 12% on 30×30 cm² circuits. First CIGSSe-cells on flexible substrates were also developed applying 30 μm thin titanium foils, 8×8 cm² in size. Average cell efficiencies on a substrate up to 12.4% were achieved.     

Vortex Dynamics in Heavy Fermion CeCoIn5

Local magnetic measurements utilizing a micro-Hall probe were performed on a superconducting heavy fermion CeCoIn₅ single crystal. We show that the critical current follows a power law as predicted by Ginzburg–Landau theory. This behavior is found to be universal in different heavy fermion and high-T _c superconducting materials. Furthermore, we report on remanent magnetization relaxation showing a high relaxation rate with approximately linear temperature dependence. Although qualitatively similar to another undoped heavy fermion, UBe₁₃, this relaxation rate is significantly higher, providing evidence that CeCoIn₅ can be grown in the clean limit.