Fluorometric detection

Kotani, N. and Takasaki, S., Analysis of 2-aminobenzamide-labeled oligosaccharides by high-pH anion-exchange chromatography with fluorometric detection, Anal. Biochem., 264, 66, 1998. 

Lin, S. L., Inoue, Y., and Inoue S., Evaluation of high-performance anion-exchange chromatography with pulsed electrochemical and fluorometric detection for extensive application to the analysis of homologous series of oligo-and polysialic acids in bioactive molecules, Glycobiology, 9, 807, 1999. 

Liu, J., Shirota, O., Wiesler, D., and Novotny, M., Ultrasensitive fluorometric detection of carbohydrates as derivatives in mixtures separated by capillary electrophoresis, Proc. Nat. Acad. Sci., 88, 2302, 1991. 

Flora, K. and Brennan, J.D. (1998) Fluorometric detection of Ca2 based on an induced change in the conformation of sol-gel entrapped parvalbumin. Analytical Chemistry, 70, 4505-4513. 

Scheper T., Bueckmann A.F., A fiber optic biosensor based on fluorometric detection using confined macromolecular nicotinamide adenine dinucleotide derivatives, Biosens. Bioelectron. 1990 5 125. 

Tributyltin has been determined in estuarine waters by high-performance liquid chromatography with fluorometric detection in a method described... 

The classic work of Dawson and Pritchard [264] on the determination of a-amino acids in seawater uses a standard amino acid analyser modified to incorporate a fluorometric detection system. In this method the seawater samples are desalinated on cation exchange resins and concentrated prior to analysis. The output of the fluorometer is fed through a potential divider and low-pass filter to a comparison recorder. 

In conclusion, CL ISH has proved more sensitive than ISH followed by colorimetric detection and can be as sensitive as ISH using radioactive labels [31, 32, 64, 65], When compared with fluorometric detection, CL showed an improved signal-to-noise ratio, thus a higher specific detectability furthermore, once standardized, it provided more precise and accurate quantitative results. 

Ho H-A, Boissinot M, Bergeron MG, Corbeil G, Dore K, Boudreau D, Leclerc M (2002) Colorimetric and fluorometric detection of nucleic acids using cationic polythiophene derivatives. Angew Chem Int Ed 41 1548-1551... 

Ho et al. were able to verify the a-helical shape of the polymer by circular dichroism (CD) spectra. No structural elements were observed until the formation of the double helical DNA at which point they observed a right-handed a-helix in the polythiophene backbone. Their work demonstrates the power of fluorometric detection as they noted a seven order of magnitude increase in detection sensitivity (20 fM in 200 pi) simply through the use of fluorometric detection as opposed to UV-vis absorption. The polymer in solution has a high fluorescence yield with a maximum at 530 nm (Fig. 11a). Upon formation of the duplex the fluorescence is significantly quenched (Fig. lib), while with the addition of the complementary DNA and triplex formation, the fluorescence intensity is enhanced by a factor of 5 (Fig. 11c). The inherent sensitivity of the spectral shift even allowed distinction between DNA with only one and two mismatched bases (Fig. lOBd, e). 

When an analyte is fluorescent, direct fluorometric detection is possible by means of a spectrofluorometer operating at appropriate excitation and observation wavelengths. This is the case for aromatic hydrocarbons (e.g. in crude oils), proteins (e.g. in blood serum, in cow milk), some drugs (e.g. morphine), chlorophylls, etc. Numerous fields of applications have been reported analysis of air and water pollutants, oils, foods, drugs monitoring of industrial processes monitoring of species of clinical relevance criminology etc. 

Rabaioli G., Taglietti A. (2001) Fluorometric Detection of Anion Activity and Temperature Changes, in Valeur B. and Brochon J. C. (Eds), New Trends in Fluorescence Spectroscopy. Applications to Chemical and Life Sciences, Springer-Verlag, Berlin, pp. 209-27. 

J. Wangsa and M. A. Arnold, Fiber-optic biosensor based on the fluorometric detection of reduced nicotinamide adeneine dinucleotide, Anal. Chem. 60, 1080-1082(1988). 

K. Sauda, T. Imasaka and N. Ishibashi, Determination of protein in human serum by high-performance liquid chromatography with semiconductor laser fluorometric detection, Anal. Chem. 58, 2649-2653 (1986). 

Static In this case, the distribution of lifetimes is due to the existence of a continuum of conformational microstates, each characterized by its own lifetime. For time-resolved fluorometric detection of heterogeneity in this case, it is necessary for the rate of transition between such microstates to be slower than that of emission. 

See Figure 8. HPLC equipment using reversed phase separation with fluorometric detection was used. Injection for correlation HPLC was accomplished with a newly developed device ( 4 ). The total range of phenol measured was five decades of concentration 0.01 -100 jug/L. The two higher concentrations (10 - 100 /i-g/L) were determined solely by conventional methods. The two lower concentrations (0.01 - 0.1 /xg/L) were determined by correlation HPLC with 16 and 3 sequences correlation time, respectively. Measurements at the 1 /xg/L level were carried out both by conventional and by correlation HPLC (1 sequence). The bars indicated on the calibration graph represent the peak area +3 (arbitrary units), where is the standard deviation... 

Figure 8. Calibration graph of phenol with fluorometric detection.

Mancinelli and colleagues (1999) reported the simultaneous determination of 3-4-methylenedioxymethamphetamine (MDMA), N-ethyl-3,4-methylenedioxyamphetamine (MDEA), methylenedioxyamphetamine (MDA), and N-methyl-l-(l,3-benzdioxol-5-yl)-2-butamine (MBDB) by RP-HPLC with fluorometric detection. The method required a 100 pi sample volume of serum, urine, or saliva separation was achieved on a LiChrospher lOORP-18 analytical column using an acetonitrile/water mobile phase (pH 11.4) set at a flow rate of 1 ml/min. The LLOQ and LLOD were 50 and 10 ng/ml respectively. 

Galvan A, Smith Y, Wichmann T. 2003. Continuous monitoring of intracerebral glutamate levels in awake monkeys using microdialysis and enzyme fluorometric detection. J Neurosci Methods 126(2) 175-185. 

The pesticides methyl and ethyl parathion were determined in run-off water er preconcentration on XAD-2. This allowed analyses of these compounds at the parts per billion level (497). Parathion and paraoxon obtained from leaf extracts and orchard soil have also been determined (492). The separation of 30 carbamate pesticides by RPC has been described (493). Various modes of postcolumn fluorometric detection of carbamate insecticides have been reported including post-colun)n reaction between o-phthalaldehyde and methylamine, a carbamate hydrolysis... 

Zgorka and Kawka [356] applied RP-HPLC both with UV detection and fluorometric detection in assessing the phenolic concentration in Eleutherocossus senticosus root preparation whose properties are considered similar to Ginseng. Amaral et al. [357] fnlly characterized the phenolic profile of walnut leaves extract, which is used as a folk medicine. Jnglone (5-hydroxy-l,4-naphtoqninone), which is characteristic of the fresh leaves, was fonnd in very low concentration, due to polymerization phenomena. Therefore, this componnd is nnsuitable for qnality control of this drng. 

When the amount of thiamine is relatively high, U V detection at 254nm can be applied. Fluorometric detection, however, enables to reach higher sensitivity, when coupled with precolumn or postcolumn derivatization. The derivatization is carried out by using potassium ferricyanide under alkaline conditions to convert thiamine to highly fluorescent thiochrome derivatives. 

This paper presents analysis methods for compounds fo defermine fheir general biological acfivity. Characferisfics of the methods in model systems using different antioxidant reaction mechanisms are also described. Both colorimetric methods and those with fluorometric detection as well as chemiluminescence testing are included. 

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