Dansyl hydrazine

Figure 14 Representative fluorescence derivatization reagents used for PO-CL detection. DNS-CI, dansyl chloride DBD-F, 4-(A,A-dimethylaminosulphonyl-7-fluoro-2,l, 3-benzoxadiazole NDA, naphthalene-2,3-dicarboxaldehyde DNS-H, dansyl hydrazine DBD-H, 4-(iV,iV-dimethylaminosulphonyl-7-hydrazino-2,l,3-benzoxadiazole).

Kawasaki T, Maeda M, Tsuji A (1983) Immobilized -hydroxysteroid dehydrogenase and dansyl hydrazine as a pre-labeling reagent for high-performance liquid chromatography with fluorescence detection of bile acids. J Chromatogr 272 261-268... 

Aldehydes, hydrazine I-Dimethylaminonaphthalene-5-sulfonyl hydrazine (dansyl hydrazine)... 

DMQPH = 6,7-dimethoxy-l-methyl-2(177j-quinoxalinone-3-proprionylcarboxylic acid hydrazide, HCPI = 2-(4-hydrazinocarbonylphenyl)-4,5-diphenyli-midazole, DBPM = 7V-[4 (6 dimethylamino-2-benzofuranyl)phenyl]maleimide, DNS-H = dansyl hydrazine, DBD H = 4 (AA -dimethylaminosulphonyl) 7-hydrazino-2,l,3-benzoxadiazole, DETBA = l,3-diethyl-2-thiobarbituric acid, DCIA = 7-dimethylamino-3- 4-[(iodoacetyl)amino]phenyl -4-methylcou marin, m-CED = 1, 2-bjs(3-chlorophenyl)ethylenediamine. 

Dimethoxy 1 methyl 2(1//) quinoxalinone-3-proprionylcarboxylic acid hydrazide Dimethyl sulfide Dimethyl sulfoxide Deoxyribonucleic acid 5is-(2,4-dinitrophenyl) oxalate Dansyl chloride Dansyl hydrazine... 

Avigad, G., Dansyl hydrazine as a fluorimetric reagent for thin-layer chromatographic analysis of... 

Aldehydes p-N itrobenzyloxy-amine HC1 (PNBA) Dansyl hydrazine... 

A high degree of sensitivity and selectivity can be obtained with certain biomolecules by the chemical attachment of fluorophores. The most common fluorescent derivatization reagents include fluorescamine, dansyl chloride, pyridoxal, pyridoxal 5-phosphate, dansyl hydrazine, and pyr-idoxamine. Such derivatization procedures can be used to enhance the fluorescence of compounds with low quantum yields as well as impart fluorescent properties to compounds that do not fluoresce naturally. 

A less costly alternative to fluorescamine is o-phthaldehyde (OPT), the derivatives of which are more stable and consequently can be stored overnight if necessary. It is used in a similar manner to fluorescamine the detection limits being about 0.1 ng ca. 4 x g/ml). OPT has been used in the analysis of dopamine, catecholamines and histamines. Other fluorescence reagents that are sometimes used include 4-bromoethyl-7-methoxycoumarin, diphenylindene, sulphonyl chloride, dansyl-hydrazine and a number of fluorescent isocyanates. 

Analytical Methods.—Convenient new methods are described for the estimation of steroidal alcohols and ketones as fluorescent derivatives. 1-Dimethylamino-naphthalene-5-sulphonyl chloride [ dansyl chloride 550)] reacts with steroidal alcohols to provide fluorescent esters which are suitable for thin-layer chromatography.The corresponding sulphonyl hydrazine [ dansyl hydrazine (551)] provides similar fluorescent derivatives of steroidal ketones. A fluorescent... 

A pre-column derivatisation technique using dansyl hydrazine is used for the quantitative analyses of glucose in blood or vitreous humour in cases of people suffering from hypoglycaemia and hyperglycaemia. 

The following additional chromophores were investigated Rhodamine B (131), Indo-1 (132), Coumarin 307 (133), Cascade Blue (134), Lucifer Yellow (135), Dansyl Hydrazine (136), DAPI (137), and Bodipy (138) [85]. 

The carbonyl absorption at around 280 nm can be used to see oxidation in polypropylene directly but this is only possible in heavily oxidised samples which are also too brittle to be sectioned for microscopy. It is possible in this way to look only at samples which have been directly crystallised from the melt as thin films. In order to work with samples with more normal oxidation levels we must stain the oxygen containing groups to make them uv absorbing. In principle it should be possible to separately stain carbonyl or peroxide groups but we have concentrated on 2,4-dinitrophenylhydrazine (I IPH) as a stain for carbonyl groups. Dansyl hydrazine was also tried as a fluorescent stain but was limited in its ability to penetrate the sample so that only the surface was stained. 

The coloured p-nitro- and 2,4-dinitrophenylhydrazones are ideal derivatives for the separation and characterization of carbonyls by paper, thin-layer and column chromatography. The oximes can easily be revealed on the thin-layer plates by spraying with solutions of copper(Il) chloride or copper(II) acetate (alcoholic) or iron(III) chloride [21,22]. For the visualization of carbonyl compounds by means of fluorogenic labeling by Schiff base formation with reagents such as dansyl-hydrazine, we refer the reader to Chapter 9. 

In addition, carbohydrates can be derivatized to produce UV or fluorescent species to improve detection. As with the amino acids, both precolumn and postcolumn derivatization are used. Precolumn derivatization influences the chromatographic behavior of the compounds. For UV detection, phenyl-isocyanate derivatization can be used together with RP-HPLC or benzoyl chloride and 4-bromobenzoyl chloride derivatization together with normal-phase chromatography. When fluorescence detection is preferred, dansyl hydrazine and aminopyridine derivatives can be analyzed using RPC. 

Table 5. Detemiination of malonaldehyde (MDA) by the TEA test and by HPLC of the dansyl hydrazine derivative ...

Hirayama T, Yamada N, Nohara M and Fukui S (1984), The high performance liquid chromatographic determination of total malondialdehyde in vegetable oil with dansyl hydrazine , J Sci Food Agric, 35, 338-344. 

FIGURE 2.1 Reagents for introducing a fluorophore into compounds with a complementary reactive functional group. Reagents 1 = dansyl chloride 2 = dabsyl chloride 3 = dansyl hydrazine 4 = fluorescamine 5 = 2,4-dihydro-6,7-dimethoxy-4-methyl-3-oxo-quinoxaline-2-carbonyl azide 6 = o-phthalaldehyde 7 = fluorenyhnethyloxycarbonyl chloride 8 — 4-bromome iyl-7-methoxycoumarin and 9 = 4-chloro-7-nitrobenzofurazan. 

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