Fluorescence active

The detection and determination of traces of cobalt is of concern in such diverse areas as soflds, plants, fertilizers (qv), stainless and other steels for nuclear energy equipment (see Steel), high purity fissile materials (U, Th), refractory metals (Ta, Nb, Mo, and W), and semiconductors (qv). Useful techniques are spectrophotometry, polarography, emission spectrography, flame photometry, x-ray fluorescence, activation analysis, tracers, and mass spectrography, chromatography, and ion exchange (19) (see Analytical TffiTHODS Spectroscopy, optical Trace and residue analysis). 

The ability to display proteins on the surface of an organism has been exploited as a screening method, typically in conjunction with fluorescence-activated cell sorting (FACS) [37,47,48]... 

Becker, S., Schmoldt, H.U., Adams, T.M. et al. (2004) Ultra-high-throughput screening based on cell-surface display and fluorescence-activated cell sorting for the identification of novel biocatalysts. Current Opinion in Biotechnology, 15, 323-329. 

The chemical composition of particles can be just as varied as their shape. Commercial particles can consist of polymers or copolymers, inorganic constructs, metals and semiconductors, superparamagnetic composites, biodegradable constructs, and synthetic dendrimers and dendrons. Often, both the composition of a particle and its shape govern its suitability for a particular purpose. For instance, composite particles containing superparamagnetic iron oxide typically are used for small-scale affinity separations, especially for cell separations followed by flow cytometry analysis or fluorescence-activated cell sorting (FACS). Core-shell semiconductor particles, by... 

Abou-Samra, A.B., Freeman, M., Juppner, H., Uneno, S., and Segre, G.V. (1990) Characterization of fully active biotinylated parathyroid hormone analogs. Applications to fluorescence activated cell sorting of parathyroid hormone receptor bearing cells./. Biol. Chem. 265, 58-62. 

J. Kruger, K. Singh, A. O Neill, C. Jackson, A. Morrison, and P. O Brien, Development of a microfluidic device for fluorescence activated cell sorting. J. Micromech. Microeng. 12, 486-494 (2002). 

Van Duuren [37] examined the use of emission and excitation spectra in the identification of aromatic hyorocarbons. Contour diagrams of fluorescence activity at various excitation and emission wavelengths have been used as a means of identifying petroleum residues. 

Fluorescence-activated cell sorter, 26 971 Fluorescence band maxima, 20 512 Fluorescence detection, 17 635 Fluorescence detectors, liquid... 

AEOs have been analysed by HPLC and UV or fluorescence detection after suitable derivatisation. The derivatising agents proposed so far are phenyl isocyanate [80,81], 1-anthroylnitrile [82], 3,5-dinitro-benzoyl chloride [83], naphthyl isocyanate [84] and naphthoyl chloride [84], However, the lack of fluorescence activity and the need for synthesis through a multistep reaction for some derivatising agents limits their application in a real-world analysis. In fact, only a few of them were applied in the determination of AEOs in environmental samples. Zanette et al. [84] developed derivatisation and separation... 

Kubo Y, Kato M, Misawa Y et al (2004) A fluorescence-active l,3-bis(isothiouronium)-derived naphthalene exhibiting versatile binding modes toward oxoanions in aqueous MeCN solution new methodology for sensing oxoanions. Tetrahedron Lett 45 3769-3773... 

Few groups of chromophores exhibit absorbance or fluorescence activity due to electronic transitions in the NIR region. Furthermore, very few dyes are commercially available that could be used in probe applications. The limited commercial availability of NIR-absorbing fluorophores, especially functionalized dyes, is probably the major obstacle in the further development of NIR OFCD. However, the synthesis of several NIR dyes has been reported 39 3 and has been applied successfully in NIR... 

The molecular absorption intensity of polar compounds is usually small, but highly sensitive detection can be obtained after pre- or post-column derivatiza-tions. The use of ultraviolet absorption or fluorescence-active counter-ions makes it possible to achieve highly sensitive detection of polar compounds and enhance the capability of ion-pair liquid chromatography. For example, N,N-dimethylprotriptyline has been used as a counter-ion for carboxylic acids12 and picric acid for quaternary amines13 in normal-phase ion-pair partition liquid chromatography. Phenethylammonium, cetylpyridinium, l-phenethyl-2-pyco-linium, and naphthalene-2-sulfonic acid have been used for sulfonic acid and alkyl amines detection.14,15 Ion-pair post-column extraction was applied on-line for fluorescence detection.16... 

A fluorescence-activated cell sorter (FACS) is a flow cytometry instrument used to separate and identify cells in a heterogeneous population. Cell mixtures to be sorted are first bound to fluorescent dyes such as fluorescein or phycoerythrin. The labeled cells are then pumped through the instrument and are excited by a laser beam. Cells that fluoresce are detected, and an electrostatic charge is applied. The charged cells are separated using voltage deflection. 

Electronic Standards for Transmission of Regulatory Information European Union antigen-binding fragment fluorescence-activated cell sorter fetal bovine serum constant fragment... 

Stiles, B.G., Blocker, D., Hale, M.L., Guettholf, M.A. and Barth, H., Clostridium botulinum C2 toxin binding studies with fluorescence-activated cytometry, Toxicon, 40, 1135-1140, 2002. 

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