Fluorescence, acridine

Variation of Experimental Rate Constant /tQ with Ionization Potential of Quencher of Acridine Fluorescence in Aqueous NaOH (0.03M)... 

Quenching of acridine fluorescence in aqueous solution (0.03 M NaOH) at 25°C. 

The intramolecular interaction of the 9-aminoacridine dye quinacrine with the nucleobases attached via a flexible polymethylene linker has been studied by Constant et al. [100]. The dye and nucleobase form r-stacked intramolecular complexes in water and, to a lesser extent, in organic solvents. Complex formation with adenine or thymine results in an increase in the acridine fluorescence intensity, presumably due to decreased solvation by water. In contrast, complexation with guanine results in quenching of the acridine fluorescence, presumably due to electron transfer. 

TABLE 6. Critical Micelle Concentrations detarmined by the Acridine Fluorescence Method in Comparison with Other Methods... 

Elema RP, Michels PAM and Konings WN (1978) Response of 9-amino-acridine fluorescence to transmembrane pH-gradients in chromatophores from Rhodopseudomonas sphaeroides, Eur.J.Biochem. 92, 381-387. 

Figure 2 ATP dependent 9-amino-acridine fluorescence change in CFq-CFi proteoliposomes. Preparations as in Fig. 1. 9-aminoacridine (9AA) responses were measured in the same reaction mixture, except that 9AA replaced oxonol, in a Perkin-Elmer spectrophoto-fluorometer using for excitation 420 nm and for emission 465 nm.

Of interest, and occasional importance (in whiteness enhancers, for instance), are the fluorescent properties of heterocyclic compounds. Fluorescence is quite frequently found in the compounds relevant to this volume the acridines and acridones show it particularly often, but it appears in a number of very diverse systems. The fluorescence and phosphorescence of heterocyclic molecules have been reviewed by Schulman <74PMH(6)147). 

A highly sensitive method for the determination of anionic surfactants, particularly sodium dodecyl sulfate, has been described [275]. The method is based on the formation of fluorescent ionic complexes of the anionic surfactant with acridine red and acridine yellow. The complexes are extracted with dichloro-... 

Another morphological assay of apoptosis is done with acridine orange, a nuclear staining that reveals chromatin condensation under light and fluorescent microscope. 

Acridine orange changes its fluorescence color from pale yellow-green to yellow in a specific pH range (pH 8-10) [1, 4]. 

Acridine orange, pH-dependent change of fluorescence color 91 Activation of the layer 124ff. N-Acylglycine conjugates 176 ADB = 2-amino-2, 5-dichlorobenzophe-none 227... 

It had been found that if bacteria are stained with acridine orange and examined under fluorescent microscopy, viable, as dishnct from dead, cells fluoresce with an orange-led hue. This basic observation has been adapted to an ingenious method of determining bacterial content and may be completed within 1 hour. 

Solubilization of an active H,K-ATPase is also a prerequisite for reconstitution of the enzyme into liposomes. With these H,K-ATPase proteoliposomes it is then possible to study the transport characteristics of pure H,K-ATPase, without the interference of residual protein contamination that is usually present in native vesicular H,K-ATPase preparations. Rabon et al. [118] first reported the reconstitution of choleate or n-octylglucoside solubilized H,K-ATPase into phosphatidylcholine-cholesterol liposomes. The enzyme was reconstituted asymmetrically into the proteoliposomes with 70% of the pump molecules having the cytoplasmic side extravesicular. In the presence of intravesicular K, the proteoliposomes exhibited an Mg-ATP-dependent H transport, as monitored by acridine orange fluorescence quenching. Moreover, as seen with native H,K-ATPase vesicles, reconstituted H,K-... 

The pH indicator shows the acid or basic properties of sample molecnles. Commonly used for acid indicating are solutions of bromocresol green (20 mg dissolved in 10 ml of ethanol combined with 1 ml of 0.1-molar aqueous NaOH) or bromophenol blue (20 mg dissolved in 10 ml of ethanol, pH-adjusted with 0.1-molar NaOH or 0.2% aqneous citric acid). In the presence of acids, 2,6-dichloroindophenol (40 mg dissolved in 100 ml of ethanol) changes the color from blue to red. The fluorescent dye acridine orange (20 mg dissolved in 100 ml of ethanol) changes pH-dependently the color of its flnorescence from yellow-green to yellow. 

This chapter focuses on recent developments in the design and applications of fluorescent organic markers, such as coumarins, benzoxadiazoles, acridones, acridines, polyaromatics (naphthalene, anthracene, and pyrene), fluorescein, and rho-damine derivatives, which display maximum fluorescence emission in the UV/ visible region and have been applied in the labeling of relevant biomolecules, namely DNA, RNA, proteins, peptides, and amino acids, among others. 

Acridine and its derivatives are also fused nitrogen heterocycles similar to acridones, which display a high fluorescence quantum yield and possess the ability to intercalate tightly, though reversively, to the DNA helical structure [73], with large binding constants [74]. As a result, acridine dyes are recognized in the field of the development of probes for nucleic acid structure and conformational determination [75-77]. 

Wu M, Wu W, Gao X et al (2008) Synthesis of a novel fluorescent probe based on acridine skeleton used for sensitive determination of DNA. Talanta 75 995-1001... 

Anthracene has also been used as an acceptor (Fig. 10). In solution, 26 emits a single fluorescence band that is somewhat structured in nonpolar solvents and becomes broad and structureless with increasing polarity [58]. The strongly hindered molecule 27 also exhibits a similar behavior, but its absorption spectrum is better structured [59]. The rate of formation of a charge transfer state is higher for 27 than for 26. Based on this observation, it appears that the twist around the anthryl-phenyl C-C bond plays a significant role in the fluorescence profile of the probes [60]. Acridines, such as 28, behave similarly to anthracene except that acridine is a better electron acceptor [61]. 

Diverdi LA, Topp MR (1984) Subnanosecond time-resolved fluorescence of acridine in solution. J Phys Chem 88(16) 3447-3451... 

When acridane 1 is oxidized by dibenzoyl peroxide in propanol/ water in acid or neutral medium, there occurs chemiluminescence whose emission spectrum matches the fluorescence spectrum of acridinium cation (protonated acridine) 2. As radical scavengers have no influence... 

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