L-Anilino-8-naphthalene sulfonate

One of the most well known polarity probes is ANS (l-anilino-8-naphthalene sulfonate), discovered by Weber and Lawrence in 1954. It exhibits the interesting feature of being non-fluorescent in aqueous solutions and highly fluorescent in solvents of low polarity. This feature allows us to visualize only hydrophobic regions of biological systems without interference from non-fluorescent ANS molecules remaining in the surrounding aqueous environment. 

The dye l-Anilino 8-Naphthalene Sulfonic acid (ANS) has high specificity for protein. It fluoresces only when bound to protein [30]. In smears and handsections (i.e. unembedded materials) we have never observed it to effect emulsion stability in the manner more traditional protein dyes such as Coomassie Brilliant Blue or Fast Green often do. This relative pH independence probably is due to the mode of action of this dye. It becomes fluorescent in hydrophobic pockets on protein molecules [30] in contrast to the ionic bonding necessary for Fast Green FCF and Coommassie Blue [22]. We have not observed a strong cross-reaction with lipids, either, although a fluorescence of different spectral characteristics sometimes is seen. 

Properties of Plasteins. Plasteins are generally characterized by their low solubility in water. If during the resynthesis reaction a part of the product becomes insoluble, this serves as a driving force. Aso et al. (56, 57) investigated some physicochemical properties of a water-insoluble fraction of a plastein produced from a soybean globulin hydrolysate. This fraction interacted with l-anilino-8-naphthalene sulfonate (ANS) to give a new and larger ANS emission spectrum at 450 nm (Table II). 

Evidence has been accumulated that shows that transaldolase is a half the sites enzyme, in which binding of substrate to one site almost completely inactivates the other active site. As mentioned above, only 1 mole of substrate is bound to the active site, even though the enzyme is a dimer. In the presence of excess F-6-P a burst of one equivalent of G-3-P is produced followed by a slower conversion of F-6-P to G-3-P plus DHA. It appears therefore, that the blocking of one active site by adduct formation with dihydroxyacetone results in a modified second active site which is able to slowly cleave F-6-P [76], This second site behavior is identical to that found in transaldolase in which one active site has been modified by reducing the dihydroxyacetone adduct with borohydride. Photo-oxidation of one of the two histidine residues in isoenzyme III results in the loss of activity of the enzyme, as is consistent with half-sites reaction [77]. The dye l-anilino-8-naphthalene sulfonate on the other hand is bound with 2 moles of dye per mole of enzyme, indicating two binding sites for F-6-P [78]. 

Tables 2.1 and 2.2 give two examples concerning the positions of the absorption and emission of the fluorescence probes l-anilino-8-naphthalene sulfonate and 6-propionyl-2-(dimethylamino)naphthalene or PRODAN with the solvent. We can notice that for both fluorophores, the Stokes shift decreases with the decrease of the polarity of the solvent.

Other two probes, l-anilino-8-naphthalene sulfonate (ANS) and 2-p toluidinylnaphthalene-6-sulfonate (TNS) ... 

N. Kitamura, N. Sakata, H-B. Kim, S. Habuchi, Energy gap dependence of the nonradiative decay rate constant of l-anilino-8-naphthalene sulfonate in reverse micelles, Analytical Sciences 15, 431-419 (1999)... 

Thirdly, we inspected the resistance of liposomes to the enzymatic lysis. When phospholipase D was added to the preincubated suspension of liposomes which contain l-anilino-8-naphthalene-sulfonate (ANS) close to the membrane surface, the fluorescence from ANS was effectively quenched upon the release of ANS to the bulk aqueous phase (Fig. 4). This quenching was effectively... 

The decrease in the value of was also observed for the fluorescent probe 1-anilino-8-naphthalene sulfonate (ANS) in presence of apomyoglobin. In fact, the absorption peak shift from 265 mu when free in solution to 271 mu in presence of apomyoglobin while the extinction coefficient decreases from 19200 to 13000 cm / mmole L, (Fig. 1.15). 

Abbreviations EPR, electron paramagnetic resonance FITC, fluorescein-5 -isothiocyanate lAEDANS, iV-iodoacetyl-N -(5-sulfo-l-naphthyl)ethylenediamine NCD, fluorescent yV-cyclohexyl-N -(4-dimethyl-amino-a-naphthyl)carbodiimide RITC, rhodamine-5 -isothiocyanate DPPE, dipalmitoylphosphatidyl-ethanolamine PE, egg phosphatidyl-ethanolamine ANS, 8-anilino-l-naphthalene sulfonate DPH, diphenylhexatriene e-ADP, l,iV -ethanoadenosine-5 -diphosphate TNP-ADP, 2 [3 ]-0-(2,4,6-trinitrophe-nyl)adenosine-5 -diphosphate. 

As one of the probes, fluorescence compounds are known. The fluorescence probe such as 8-anilino-l-naphthalene sulfonic acid ammonium salt(ANS) has been used as an indicator of membrane... 

Figure 42. 8-Anilino-l-naphthalene sulfonic acid (ANS) binding assay of the protyrosinase (pro-TY, —) and acid-activated tyrosinase (acid T Y, —).

Also, HPLC methods with electrochemical or fluorescent detection are used (H19, M3). In proteins, dityrosine can be estimated by immunochemical methods employing dityrosine-specific antibodies (K5). Measurements of o,o -dityrosine and o-tyrosine levels in rat urine express dityrosine contents in skeletal muscle proteins, and have been proposed as the noninvasive oxidative stress test in vivo. One should be aware, however, that A-formylkynurenine, also formed in protein oxidation, has similar fluorescence properties as dityrosine (excitation 325 nm, emission at 400-450 nm) (G29). Also, oxidation of mellitin when excited at 325 nm produces an increase in fluorescence at 400—450 nm, despite the fact that mellitin does not contain tyrosine. Oxidation of noncontaining Trp residues ribonuclease A and bovine pancreatic trypsin inhibitor with "OH produces loss of tyrosine residues with no increase in fluorescence at 410 nm (S51). There are also methods measuring the increased hydrophobicity of oxidized proteins. Assays are carried out measuring protein binding of a fluorescent probe, 8-anilino-l-naphthalene-sulfonic acid (ANS). Increase in probe binding reflects increased surface hydrophobicity (C7). 

A number of examples of the use of host-guest chemistry in the creation of PET active systems have appeared. The reaction of P-cyclodextrin alcoholate with meso-tetrakis(pentafluorophenyl)porphyrin is reported to give a hydrophilic cyclodextrin-porphyrin conjugate in 14% yield. ° In the presence of guests such as 1,4-benzoquinone, anthraquinone-2-sufonate or 8-anilino-l-naphthalene sulfonic acid, PET operates as evidenced by the fluorescence... 

The molecular group giving rise to fluorescence is termed fluorophore (fluorescence chromophore). The main fluorophores can be classified into natural fluorophores such as tryptophan residue in proteins, NAD(P)H, FMN/FAD and fluorescent indicators (probes) such as dansyl chloride, 8-anilino-l-naphthalene sulfonate (ANS), and ethidinm bromide. Nucleic adds do not have appreciable fluorescence, except for a minor base (Y-base) in tRNA (Table 7.4). 

Mixture of LR-CyDs) CA(S)[= l and CA(L)W Spectrofluorometry 8-Anilino-l-naphthalene sulfonic acid 64... 

Mixed surfactant systems can be investigated by the use of certain probes. Ultraviolet-visible spectra can provide information on the state of mixed micelles, the cmc value, and whether the interaction between different components in mixed micelles is taking place. Meguro and co-workers pioneered the use of this method to study the surfactant mixture system. In their extensive study, probes, tetracyanoquindimethane [55-58], benzoylacetone [59], beznoylacetoanilide [60,61], sodium (p-sulfonatophenylazo-l-naphthol-2-sulfonate) [62,63], and 8-anilino-naphthalene sulfonic ammonium salt [64] were examined. Using the probe method, Meguro and co-workers [64] confirmed the existence of mixed micelles between hydrocarbon-fluorocarbon surfactant, which was a controversial question before. 

The following experimental data are given for the reciprocal polarization (1/p) as a function of T/ri for adsorbates of l-anilino-naphthalene-8-sulfonic acid on BSA at 25°C in solutions of sucrose in water ... 

A H-n.m.r. study on a 2 1 chromomycin A3-Mg complex in methanol has been undertaken in order to show the importance of the carbohydrate moiety in controlling the shape of the antibiotic. Based on n.m.r. data and inspection of Corey-Pauling-Koltun models, the probable structure of the inclusion complex between 8-anilino-l-naphthalene sulfonate and 2,6-di-C)-methyl-cyclomaltoheptaose has been determined. ... 

The interaction between borate ions and a series of carbohydrates (sucrose, D-fructose and D-glucose) in aqueous solution have been examined using calorimetry, and thermodynamic parameters are available for the inclusion complex of 8-anilino-l-naphthalene sulfonate with 2,6-... 

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