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81.
Fluorimetric Determination of Histamine in Fish Using Micellar Media and Fluorescamine as Labelling Reagent 总被引:1,自引:0,他引:1
Adamou R Coly A Douabalé SE Saleck ML Gaye-Seye MD Tine A 《Journal of fluorescence》2005,15(5):679-688
An analytical method based on the use of fluorescamine to produce a fluorescent derivative with histamine and combined with
micellar-enhanced fluorescence detection of the formed complex is developed for the sensitive and rapid determination of histamine
in fishes. The fluorescence properties of the obtained complex in water and micellar solutions of sodium dodecyl sulfate (SDS),
cetyltrimethylammonium chloride (CTAC) and brij-700 are reported. Physicochemical variables influencing the sensitivity of
the method (pH, micellar, fluorescamine and NaCl relative concentrations) have been optimized. The stability of the formed
complex, as shown by kinetic study, depends on the pH of the solution. Linear calibration curves allowing an effective histamine
determination were established with large linear dynamic range (LDR), and low limits of detection (LOD) between 0.5 and 33
ng mL−1, according to the solvent. Application to the analysis of fish samples (sardines) yielded satisfactory results. The method
seems to be suitable for environmental fish quality control.
Presented in part, at the 39th IUPAC Congress and the 86th Conference of the Canadian Society for Chemistry, August, 10–15,
2003, Ottawa (Canada). 相似文献
82.
Zou L Wang J Beleva VJ Kooijman EE Primak SV Risse J Weissflog W Jákli A Mann EK 《Langmuir : the ACS journal of surfaces and colloids》2004,20(7):2772-2780
A systematic study of five different, symmetric bent-core liquid crystals in Langmuir thin films at the air/water interface is presented. Both the end chains (siloxane vs hydrocarbon) and the core (more or less amphiphilic) are varied, to allow an exploration of different possible layer structures at the interface. The characterization includes systematic surface pressure isotherms, Brewster angle microscopy, and surface potential measurements. The properties of these layers are strongly dependent on the individual type of molecule: the molecules with amphiphilic end chains lie quite flat on the surface, while the molecules with hydrophobic end chains construct multilayer structures. In both cases, the three-dimensional collapse structure is reversible. 相似文献
83.
Barrett PA Boix T Puche M Olson DH Jordan E Koller H Camblor MA 《Chemical communications (Cambridge, England)》2003,(17):2114-2115
The new synthetic form of microporous crystalline silica, denoted as ITQ-12, shows a high potential for the separation of propane and propene from its mixtures. 相似文献
84.
85.
Edgar E. Enochs J. R. Garcí a Rozas Luis Oyonarte 《Proceedings of the American Mathematical Society》2000,128(10):2863-2868
We prove that for certain classes of modules such that direct sums of -covers ( -envelopes) are -covers ( -envelopes), -covering ( -enveloping) homomorphisms are always right (left) minimal. As a particular case we see that over noetherian rings, essential monomorphisms are left minimal. The same type of results are given when direct products of -covers are -covers. Finally we prove that over commutative noetherian rings, any direct product of flat covers of modules of finite length is a flat cover. 相似文献
86.
Ernesto San-Blas Mayamarú Guerra Edgar Portillo Iván Esteves Nestor Cubillán Ysaías Alvarado 《Vibrational Spectroscopy》2011,57(2):220-228
The use of Fourier transform mid-infrared spectroscopy with attenuated total reflection for characterizing entomopathogenic nematodes is evaluated for the first time. The resulting spectra of Steinernema glaseri and Heterorhabditis indica were compared with the spectrum of Caenorhabditis elegans. In the absorption spectra generated by the nematodes samples, the absorption bands were assigned to the molecular species and some important components were identified including triglycerides, trehalose, glycogen and collagen. Also, the use of star diagrams for the fingerprint section of nematode spectra for separating genera is discussed. 相似文献
87.
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89.
G. H. Bailey Thornton Lamb Harry F. Keller Edgar F. Smith A. Joly und E. Leidié 《Fresenius' Journal of Analytical Chemistry》1893,32(1):636-645
Ohne Zusammenfassung 相似文献
90.