Acridine In Solution Research Articles

Surface enhanced Raman scattering by a new derivative of acridine in solutions of colloidal silver

A new derivative of acridine, 4,5-bis(N,N-di(2-hydroxyethyl)iminomethyl)acridine (BHIA), which is a selective fluorophore relative to cadmium cations, is studied by the method of surface-enhanced Raman scattering (SERS). The SERS spectra of BHIA adsorbed on colloidal silver particles exhibit a high intensity and temporal stability of the signal. An assignment of the bands present in the studied spectral range is given. The dependence of the SERS spectra of BHIA on the solution’s pH reveals that the ligand can exist on the surface in protonated and deprotonated forms. The stability of the deprotonated form on the surface suggests that the ligand interacts with the surface by means of a conjugated π-system of aromatic rings. The addition of the salt of halide ions to the solution has a significant influence on the SERS spectrum. This effect is due to the displacement of the adsorbate molecules from the first monolayer, which is accompanied by the transition of BHIA from the chemi- to the physisorbed form.

Solvent Effects on Acridine Polymorphism

1H NMR dilution experiments were used to monitor self-association of acridine in solution in four different solvents. The pattern of complexation-induced changes in chemical shift is similar in chl...

Characterization of Acridine Species Adsorbed on (NH4)2SO4, SiO2, Al2O3, and MgO by Steady-State and Time-Resolved Fluorescence and Diffuse Reflectance Techniques

The ground- and excited-state species of acridine adsorbed on (NH(4))(2)SO(4), SiO(2), Al(2)O(3), and MgO surfaces were investigated in order to determine the precursor species and electronic states responsible for acridine photodegradation on particles serving as models of atmospheric particulate matter. The species present on each solid surface were characterized by comparing the steady-state absorption and fluorescence spectra, time-resolved fluorescence, and absorption measurements on acridine in solution with those corresponding to adsorbed acridine. On silica, the ground-state species present were hydrogen-bonded, neutral, and protonated, while on alumina hydrogen-bonded and neutral species were identified. A comparison of the protonated acridine absorption and emission intensities on silica and alumina with those observed for acridine in acidic water demonstrated that the emission on the surfaces is higher than expected. This was interpreted as resulting from photoprotolytic reactions on silica and alumina. For acridine adsorbed on ammonium sulfate, protonated acridine was the only adsorbed species identified. Since, at a similar ground-state absorbance, the fluorescence intensity of acridine on ammonium sulfate was smaller than for acridine in acidic water, the quenching of the excited state or a rapid photochemical reaction with the surface was proposed. On magnesium oxide, the presence of neutral and hydrogen-bonded acridine species were characterized from the two-component analysis of the fluorescence, the triplet-triplet absorption decay curves, and the time-resolved emission spectra at different time delays. As demonstrated in these studies, acridine adsorbed species and their decay pathways depend on the acidic properties of these models of atmospheric particulate matter. In addition, a comparison of the photodegradation rates of acridine on the different solids tested is presented and discussed in terms of the nature of the species and their decay pathways.

Electronic spectra of 7,14‐dithioketo‐5,7,12,14‐tetrahydroquinolino‐[2,3‐b]‐acridine in solution and in the solid state

Abstract7,14‐Dithioketo‐5,7,12,14‐tetrahydroquinolino‐[2,3‐b]‐acridine (DTQ) is a thionated derivative of quinacridone (QA) that is known as a red pigment. Thionation of QA brings about an intense near‐IR absorption in the solid state which is of practical importance for GaAsAl‐laser printers and optical information storage systems. The electronic properties of DTQ have been investigated in solution and in the solid state in order to characterize the near‐IR absorption from the standpoint of intermolecular hydrogen bonding. The electronic state of the DTQ‐chromophore is found to be most sensitively affected by an environment of proton acceptors which interact with the NH group of the chromophore. In solution, the hydrogen bonds between the NH group and the O atom of a solvent cause a bathochromic shift by 5 – 15 nm relative to the absorption spectrum in dioxane. This is interpreted as being due to electron transfer from the proton to the nitrogen atom, thereby increasing the electron density in the chromophore. A similar increase in electron density is also operative in the solid state through the intermolecular hydrogen bonds between the NH group of one DTQ and the S atom of the neighboring molecule. This is mainly responsible for the bathochromic displacement of DTQ in going from solution to the solid state. The near‐IR absorption is, however, not explicable in terms of the hydrogen bonding interaction alone. Another intermolecular interaction, such as π‐π interactions along the stacking axis, appears to be operative that might lead to a near‐IR absorption.

Triplet state (T 1) resonance Raman spectroscopy of phenazine and acridine

Resonance Raman spectra of the photoexcited lowest triplet states of phenazine and acridine in solution observed by time-resolved techniques are reported. Nine fundamentals in phenazine and fourteen in acridine are observed and assigned. The phenazine triplet (≈3 × 10 −4 M) in cyclohexane is observed to decay by a second-order process at a rate constant (2 k) of (4.8 ± 1.0) × 10 9 M −1 s −1.

Subnanosecond time-resolved fluorescence of acridine in solution

Utilisation des constantes de vitesse pour la relaxation electronique et pour les transitions radiatives, dans l'analyse de l'ordre et du melange des deux etats singulet excites les plus bas de l'acridine dans differents solvants

Radicals produced from the laser-induced photoionization of acridine in solution

We report on the transient species obtained in the biphotonic ionization of acridine in aqueous solution (pH 12.3) induced by the third harmonic of a neodymium-doped glass laser. The species directly produced during the laser pulse were the hydrated electron and the acridine cation which was detected for the first time in fluid media at room temperature. The hydrated electron and the cation decayed with pseudo-first-order kinetics, leading to microsecond transients which were assigned to two different acridine neutral radicals. The acridine cation was neutralized by the OH − present in the solution ( k = 3 × 10 8 M −1 s −1), leading to a radical (the “N radical”) characterized by an absorption around 600 nm (λ max = 595 nm; ϵ max ≈ 5000 M −1 cm −1). The hydrated electron reacted efficiently with unexcited acridine ( k = 4 × 10 10 M −1 s −1) to give a hydrogenated radical (the “C radical”) which showed a broad absorption in the visible region around 500 nm (λ max = 510 nm; ϵ max ≈ 4000 M −1 s −1).

ChemInform Abstract: PICOSECOND KINETICS OF ACRIDINE IN SOLUTION

Chemischer InformationsdienstVolume 12, Issue 15 Preparative Organic Chemistry ChemInform Abstract: PICOSECOND KINETICS OF ACRIDINE IN SOLUTION S. L. SHAPIRO, S. L. SHAPIROSearch for more papers by this authorK. R. WINN, K. R. WINNSearch for more papers by this author S. L. SHAPIRO, S. L. SHAPIROSearch for more papers by this authorK. R. WINN, K. R. WINNSearch for more papers by this author First published: April 14, 1981 https://doi.org/10.1002/chin.198115133AboutPDF ToolsRequest permissionExport citationAdd to favoritesTrack citation ShareShare Give accessShare full text accessShare full-text accessPlease review our Terms and Conditions of Use and check box below to share full-text version of article.I have read and accept the Wiley Online Library Terms and Conditions of UseShareable LinkUse the link below to share a full-text version of this article with your friends and colleagues. Learn more.Copy URL Share a linkShare onFacebookTwitterLinked InRedditWechat No abstract is available for this article. Volume12, Issue15April 14, 1981 RelatedInformation

Picosecond kinetics of acridine in solution

The fluorescence lifetime of acridine depends upon the excitation and emission wavelengths in certain solvents. The lifetime is also a sensitive function of temperature and medium, and variations are interpreted in terms of the hydrogen bonding characteristics of the solvents.

Photoreactive State of Acridine in Solution

The technique of energy transfer has been used in an attempt to establish the photoreactive state of acridine in solution. It is shown that the lowest-lying triplet of acridine, the ππ* triplet, is not the reactive species and that the reaction originates, at least in part, through the nπ* triplet. In the course of this work, the transfer of triplet-state energy from biacetyl to acridine, phenazine, anthracene, 1,2-benzanthracene, pyrene, 1,2-benzpyrene and 3,4-benzpyrene has been studied by an intensity method.