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101.
Monica Ermolli Anna Fantozzi Massimiliano Marini Domenico Scotti Branko Balla Sebastian Hoffmann Maddalena Querci Claudia Paoletti Guy Van den Eede 《Accreditation and quality assurance》2006,11(1-2):55-57
GMO protein content in maize flours or fresh crops can be easily assessed by the enzyme-linked immunosorbent assays (ELISA)
and immunochromatographic (lateral flow) strip tests commercially available. Therefore, ELISA can be seen as a useful tool
for screening, for control purposes and for traceability implementation. In order to highlight the importance of monitoring
GMO protein presence in food products and to investigate the performance of representative ELISA commercial kits, we evaluated
three commercial kits by measuring the amount of Cry1Ab/Cry1Ac in IRMM certified reference materials.
Presented at AOAC Europe/Eurachem Symposium March 2005, Brussels, Belgium 相似文献
102.
This paper reports the optimisation of a competitive immunoassay (ELISA) to detect lactosylated proteins in milk samples. The assay employs monoclonal antibodies for lactosylated proteins produced in our laboratory and requires no pre-treatment of the samples other than a dilution step. Monoclonal antibodies were fully characterised in terms of selectivity and cross-reactivity with structurally related molecules and used in a competitive assay format with lactosylated standard proteins (lactosylated ovalbumin). The detection limit for lactosylated ovalbumin was 0.015 microgram ml-1 and the working range was from 0.010 to 40 micrograms ml-1. The data obtained indicate that the ELISA developed is applicable to diluted milk samples and is able to distinguish between milk samples that have undergone different heat treatments (UHT and pasteurised milk). 相似文献
103.
Organic-inorganic hybrid coatings containing quaternary ammonium salts (QAS) bonded to the organic-inorganic network were prepared from tetraethoxysilane and triethoxysilane terminated poly(ethylene glycol)-block-poly(ethylene) using a sol-gel process. They were applied as a thin layer (0.6-1 μm) to PE films and the antibacterial activity of the coated films was tested against both Gram-negative (Escherichia coli ATCC 25922) and Gram-positive (Staphylococcus aureus ATCC 6538) bacteria. Measurements at different contact times showed a rapid decrease of the viable count for both the tested strains. In particular, after 48 h of contact, a decrease of 96.4% and 99.1% of E. coli and S. aureus, respectively, was observed. The permanence of the antibacterial activity of the coated films was demonstrated through repeated washings and prolonged immersion in physiological saline solutions at 37 °C. Indeed, due to the removal of QAS moieties by the nucleophilic attack of water, the antibacterial activity after 24 h was strongly reduced when measured on samples submitted to several washings. However, a quite good antibacterial activity was observed even on the same samples after 96 h, probably due to a spontaneous partial restoring of the QAS on the surface. Very good transparency, quite good adhesion and high wettability are further features of these hybrid coatings. 相似文献
104.
A new glycoside, hypoxoside, was isolated from rhizome of Hypoxis obtusa, a plant used in Mozambique in native medicine for the treatment of urinary diseases. The structure 1 of a diglycoside of 1-(3′,4′-dihydroxyphenyl)-5-(3″,4″-dihydroxyphenyl)-1-penten-4-yne was attributed to hypoxoside on the basis of physico-chemical determinations and chemical behaviour. 相似文献
105.
Gaggelli E Gaggelli N Maccotta A Valensin G Marini D Di Cocco ME Manetti C Delfini M 《Spectrochimica acta. Part A, Molecular and biomolecular spectroscopy》1999,(1):205-210
The copper (II) complex of amikacin in water solution at pH 5.5 was investigated by 13C-NMR. The temperature dependence of spin-lattice relaxation rates was measured and fast exchange conditions were shown to apply. The motional correlation time of the complex was approximated by the pseudo-isotropic rotational correlation time of free amikacin in water solution (tau c = 0.17 ns at 300 K). Formation of a pseudo-tetrahedral 1:1 complex was demonstrated by relaxation rates analysis and also by UV-Vis spectrophotometry. Two amino nitrogens of amikacin, together with the amide nitrogen and the hydroxyl in the hydroxyl-aminopropyl carbonyl side chain, were assigned as the copper-binding sites and a model of the complex was built by using copper-carbon distances obtained by NMR analysis as input parameters. 相似文献
106.
Marini A. Berbenni V. Bruni G. Villa M. Orlandi A. 《Journal of Thermal Analysis and Calorimetry》2002,68(2):389-396
GV150526A is a novel 2-carboxyindole derivative, recently synthesized by GlaxoWellcome, which is used in treatment or prevention
of CNS disorders resulting from neurotoxic damage. It has been prepared in three forms, F1, F2 and F3, having significantly
different hydration/dehydration behavior and/or diffraction patterns. Here, we extend the thermal analysis of these polymorphs
above 200°C, where all forms are fully dehydrated and the main thermal phenomena are decomposition and melting. Simultaneous
TG/DSC measurements have been repeated in wet and dry nitrogen atmospheres over a wide range of heating rates. Form F3 displays
a qualitatively different behavior relative to F1 and F2. This fact is interpreted as an evidence of a mechanism of decomposition
which sets F3 apart from F1 andF2. The thermal data are summarized by simple heuristic equations and few ‘apparent’enthalpies.
This revised version was published online in August 2006 with corrections to the Cover Date. 相似文献
107.
Fernandez E Ford WT Qi N Read AL Smith JG Camporesi T De Sangro R Marini A Peruzzi I Piccolo M Ronga F Blume HT Hurst RB Venuti JP Wald HB Weinstein R Band HR Gettner MW Goderre GP Meyer OA Moromisato JH Polvado RO Shambroom WD Sleeman JC von Goeler E Ash WW Chadwick GB Clearwater SH Coombes RW Kaye HS Lau KH Leedy RE Lynch HL Messner RL Moss LJ Muller F Nelson HN Ritson DM Rosenberg LJ Wiser DE Zdarko RW Groom DE Lee HY Delfino MC Heltsley BK Johnson JR Lavine TL Maruyama T Prepost R 《Physical review letters》1985,54(11):1118-1121
108.
C. Pigot J.P. de Brion A. Caillet J.B. Cheze J. Derre G. Marel E. Pauli G. Vrana G. dAgostini G. Auriemma G. Marini G. Martellotti F. Massa A. Nigro A. Rambaldi A. Sciubba S. Reucroft E.G.H. Williams 《Nuclear Physics B》1985,249(1):172-188
The production of a strange dibaryonic system called H+1 (M = 2.13 GeV/c2, S = ?1), has been studied with a missing mass spectrometer, at the CERN Proton Synchrotron, in the reaction K?d → π?H+1 and in the line-reversed reaction π+d → K+H+1 between 0.9 and 1.4 GeV/c.The reactions , ,have been studied in a missing mass spectrometer at CERN. The experiment (PS159) is well adapted to search for a signal in the missing mass X+ (B = 2, S = ?1) produced in the backward c.m.s. direction, between 2.0 and 2.3 GeV/c2. The two reactions have been analysed at three different beam settings: 1.4, 1.06 and 0.92 GeV/c for reaction (1) and 1.4, 1.2 and 1.06 GeV/c for reaction (2). 相似文献
109.
Marcello Tiecco Lorenzo Testaferri Andrea Temperini Luana Bagnoli Francesca Marini Claudio Santi 《合成通讯》2013,43(12):2167-2179
Simple alkenes react with PhSeOTf and NaN3 in MeCN to afford β-phenylseleno azides as the result of a stereospecific trans addition. The regioselectivity of the process is determined by the structure of the alkene. 相似文献
110.