A new fluorescent first generation poly(propylene amine) dendrimer (PPI), peripherally modified with 4(butylamino-substituted-1,8-naphthalimide), has been synthesized and characterized. Its photophysical characteristics in organic solvents of different polarities were studied, and the influence of sodium hydroxide on its spectral characteristics in N,N-dimethylformamide is discussed. The complexes formed between the dendrimer and metal cations in solution have been studied with regard to the potential applications of the new dendrimer as a colorimetric and fluorescent sensor for metal ions. The fluorescence intensity of the dendrimer in the presence of metal cations (Zn2+, Co2+, Pb2+, Mn2+, Cu2+ and Fe3+) increases substantially revealing its sensor potential. 相似文献
A chemosensor is reported with high sensitivity and selectivity for detection of fluoride anion. The recognition mechanism is attributed to a fluoride-triggered disruption of the hydrogen bond between imidazole and naphthalimide moieties, resulting in a noncoplanar geometry with low fluorescence. 相似文献
The synthesis of two new green fluorescent poly(propyleneimine) dendrimers from first generation has been described. The new materials are comprised of a 1,8-naphthalimide fluorophore having a substituent at C-4 position. The substituent in the first case is a N,N-dimethylaminoethylamino group while in the second one it is N-methylpiperazine. The spectroscopic and photophysical characteristics of the new dendrimers determined in organic solvent of different polarity have been presented. Both dendrimers show substantial increases in their fluorescence intensity in the presence of metal cations (Zn2+, Co2+, Ni2+, Pb2+, Mn2+, Cu2+, Fe3+ and Ag+) and protons. The influence of the photoinduced electron transfer on their sensing properties has been discussed. 相似文献
A new 4-(N-methylpiperazine)-N-allyl-1,8-naphthalimide with intense yellow-green fluorescence has been synthesized. Then it has been copolymerized with styrene and methylmetacrylate. The photophysical characteristics of the fluorescent dye and its copolymers (poly(St-co-NI) and poly(MAA-co-NI)) have been determined viewing their sensor properties for protons and transition metal cations (Cu2+, Fe3+ and Zn2+). Fluorescence enhancement is the photophysical response of the 4-(N-methylpiperazine)-N-allyl-1,8-naphthalimide to the presence of metal cations and protons, while fluorescence quenching is observed for both copolymers. 相似文献
The investigations aim at revealing the ability of a 1,8-napthalimide-modified poly(amidoamine) dendrimer from second generation to respond to the presence of cuprum cations and protons in the environment. It has been established that a single Cu(2+) cation present in the dendrimer molecule is capable of quenching more than 78% of its fluorescence what is an indication of high sensitiveness. An enhancement of the fluorescence emission of the dendrimer has been observed in acidic medium. It has been established that the processes of coordinating the ions in different sites of the dendrimer are reversible. 相似文献
A novel naphthalimide molecule, 4-(2-methoxyethoxy)-N-butyl-1,8-naphthalimide (MEBN), has been synthesized and characterized. The UV–visible absorption and fluorescence emission
spectral properties in n-hexane, toluene, CHCl3, and CH3OH were studied. Its optical properties depend on solvent polarity. The application of MEBN in cell imaging was investigated. 相似文献
This report discloses a series of naphthalimide-based bifunctional fluorescent probes for hydrogen peroxide and diols.As a result,these molecules not only demonstrated high turn-on fluorescent response and good selectivity towards hydrogen peroxide over other relevant reactive oxygen species,but also displayed different responses to diols.Therefore,these fluorescent probes could be served as sensitive,selective and practical chemosensors for both hydrogen peroxide and diols under physiologicallike conditions. 相似文献
The paper reports on synthesis and spectroscopic study of novel N-butyl-4-styryl-1,8-naphthalimide dyes bearing methoxy (1), dimethoxy (2), and dimethylamino (3) groups in the styryl fragment. It is shown that all synthesized compounds demonstrate positive solvatochromism, high values of Stokes shift in polar solvents, and fluorescence in the long wavelength part of visible range. These facts indicate a potential application of these compounds as fluorescent dyes in the biochemistry. The changes in the dipole moments of the molecules caused by excitation were estimated using Lippert—Mataga equation. The obtained results could be assigned to the formation of the excited states with intramolecular charge transfer. The formation of the twisted states with charge transfer was suggested in the case of compound 3, while the fluorescence quantum yield was significantly reduced in polar protic solvents.
A new 1,8-naphthalimide derivative bearing an aza-15-crown-5 macrocycle (1) has been synthesized as a chemosensor for Hg2+ by a two-step reaction. The sensor shows selectivity to Hg2+ over 11 other metal cations in aqueous media. Upon addition of Hg2+, the fluorescence emission of the sensor at 537 nm is significantly quenched along with 22 nm blue-shift that makes this compound a useful sensor for Hg2+ measurement. 相似文献
A new fluorescent sensor 1 based on the rhodamine amide-armed homotrioxacalix[3]arene was synthesized, and its sensing behavior toward metal ions was investigated by UV–vis and fluorescence spectroscopies. Upon the addition of metal cations (Sb3+, Fe3+, Ni2+), a significant fluorescent enhancement in the range of 500–600 nm and colorimetric change was observed. 相似文献
A composite material based on polyvinyl chloride and a 1,8-naphthalimide derivative containing an azadithia-15‑crown-5 ether receptor showed a fluorescent response to silver cations in an aqueous solution at low concentrations. 相似文献
Russian Chemical Bulletin - Complexation of 4-amino-1,8-naphthalimide derivative containing an aza-15-crown-5 ether receptor unit in the N-aryl substituent at the imide nitrogen atom of the... 相似文献
A series of fluorescent siloxane-polyurethanes(HPMS-PUs) containing an amino-functionalized,1 8-naphthalimide,fluorescent monomer(AABD) as a chain extender were synthesized.The properties of the HPMS-PUs were investigated by UV–vis and fluorescence spectroscopies,thermogravimetric analysis and thermal migration behavior.The maximum absorption and emission wavelengths of HPMS-PUs showed a red shift of about 4 nm and a blue shift of about 9 nm,respectively,compared to those of AABD.The Stokes shifts of AABD and HPMS-PU2 were 3514 and 2931 cm 1,respectively.The quantum yield of HPMS-PU2 was 0.79,which was six times higher than that of AABD.Concentration self-quenching was observed in both AABD and HPMS-PUs.The fluorescence of HPMS-PUs was quite stable with respect to both temperature and fluorescence quencher effects.The thermal stability of HPMS-PUs increased with AABD content.The fluorophore units in the HPMS-PUs did not readily migrate. 相似文献
The use of anti-1,8-bis(2,2′-diisopropyl-4,4′-diquinolyl)naphthalene, 1, for metal ion-selective fluorescence recognition has been investigated. Employing CuCl2, ZnCl2, FeCl2, and FeCl3 in fluorescence titration experiments of 1 revealed formation of a bluegreen light emitting bimetallic complex. A dramatic red-shift of the fluorescence maximum of 1 and metal ion-selective quenching was observed in the presence of Cu(II), Fe(II), and Fe(III)chlorides in acetonitrile. By contrast, addition of ZnCl2 was found to result in fluorescence enhancement, whereas Cu(I) did not induce any significant fluorescence change of 1. The sensor was found to undergo highly ion-selective fluorescence quenching in aqueous solution. Screening of main group and transition metal ions showed excellent selectivity for FeCl3 even in the presence of competing metal ions. 相似文献
Two 4,5-disubstituted-1,8-naphthalimide derivatives 1 and 2 were synthesized as ratiometric fluorescent and colorimetric sensors for Cu2+, respectively. In 100% aqueous solutions of 1, the presence of Cu2+ induces a strong and increasing fluorescent emission centered at 478 nm at the expense of the fluorescent emission of 1 centered at 534 nm. Compound 2 senses Cu2+ by means of a colorimetric (primrose yellow to pink) method with a thorough quench in emission attributed to the deprotonation of the secondary amine conjugated to the naphthalimide fluorophore. 1-Cu2+ and 2-Cu2+ sense cyanide in ratiometric way via colorimetric and fluorescent changes. 相似文献