Poly fluorescence emission

The identification of anionic polyfacrylic acid) sizes can be carried out by staining with a fluorescent cationic dye (Cl Basic Orange 14) followed by spectroscopic measurement of excitation wavelength and fluorescence emission [195,196]. Such methods can also be used (with Cl Basic Orange 14 or Cl Basic Red 1) to detect and estimate carboxymethylcellulose, poly(vinyl alcohol) and starch derivatives [197]. 

Fluorescence measurement using this probe does not require a fluorescence quencher or washing process to suppress the fluorescence emission from nonbinding probes and nonspecific binding probes, which would be advantageous for the detection of mRNAs with poly(A) tracts in cells. 

The broad emission and low-fluorescence quantum yield of PPS suggested a distribution of trapping sites in the Si skeleton, which were also considered responsible for the lower-than-expected conductivity. The far-IR spectrum of PPS suggested the existence of cyclohexasilane rings connected by linear chains.361,362 Subsequent investigations by Irie et al. on the electronic absorption spectra of radical ions of poly(alkylsilyne)s were taken to indicate the presence of various cyclic silicon species, in corroboration of this conclusion.363 The large Stokes shift and broadness of the fluorescence emission indicate a range of fluorophore structures, different from the chromophore structures. This is... 

Barja BC, Chesta C, Atvars TD, Aramendia PF (2005) Relaxations in poly(vinyl alcohol) and in poly(vinyl acetate) detected by fluorescence emission of 4-aminophthalimide and prodan. J Phys Chem B 109 16180-7... 

The hypochromicity of Ad-Q-Ad and poly-VAd corresponds to the formation of the excimer which has also been concluded from the results of the fluorescence emission spectra. The stereomodel of Ad-Q-Ad shows that the conformation in which two adenine rings are situated plane-parallel and, thus, the formation of the excimer is possible. From these considerations, it can be inferred that there exist two kinds of interactions between adenine residues exhibiting either plane-to-plane or coplanar arrangements. Both interactions can be expected to be valid for poly-VAd which includes two kinds of interactions along the polymer chain corresponding to Ad-Q-Ad and Ad-Q-Ad. This effect may give rise to high hypochromicity in the spectra of the polymer. 

UV absorption spectra, fluorescence emission spectra and photostabilization effect of 2-(2-hydroxy-4-acryloyloxyphenyl)-2/7-benzotriazole and of its polymer bound forms were studied in poly-CK-l,4-polybutadiene [337]. The following activity series was found copolymer with methyl methacrylate > homopolymer > monomer. It seems that chromophoric units incorporated into a macromolecule behave cooperatively (causing self-absorbance of the emitted radiation). 

Here we report preliminary results on the multiple fluorescence emission of 1 and 2. From structure-property relationships, solvent effect and temperature effect studies, we are able to show that the multiple emission is from the emission of free squaraine in solution, the emission of the solute-solvent complex and the emission of a twisted relaxed excited state. Further solvent effect study using 2 as a model shows that squaraine forms strong solute-solvent complexes with alcoholic solvent molecules. Analogous complex-ation process is also detected between 1 and the hydroxy groups on the macromolecular chains of poly(vinyl formal). The Important role of this complexation process on the stabilization mechanism of particles of 1 in polymer solution is discussed. 

Neat Polymer Films. It is interesting to compare the triplet photophysical properties of poly(N-vinylcarbazole) (PVCA)(16) on the one hand and poly(l-vinylnaphthalene) (PIVN)(17) on the other when each is examined as a pure polymer film. Both polymers exhibit a prominent excimer phosphorescence band as well as a distinct delayed fluorescence emission. In addition, the delayed fluorescence arises by a process of triplet-triplet annihilation for both polymers. Furthermore, the luminescence decay kinetics suggest that equilibria of the type... 

Labelling and doping of polymers continues to attract interest especially with regard to metal ions and pH effects. Poly(sodium styrenesulphonate-CO-vinylphenyl)anthracene copolymers have been prepared which appear to give compact conformations and are therefore able to solubilize large hydrophobic structures . Polymer bound ortho-hydroxyphenylbenzotriazoles have been found to exhibit a temperature dependent red fluorescence emission from a... 

The chiral polythiophene, poly(3- (.S )-5-amino-5-carboxyl-3-oxapcntyl -2,5-thiophenylene) hydrochloride, l-POWT, ring-functionalized with the amino acid L-serine, has been synthesized by Inganas and coworkers,69,168 and was found to exhibit pH-dependent UV-visible, fluorescence emission, and CD spectra. At a pH equal to the isoelectric point of the amino acid, the poly thiophene chains separate and adopt a nonplanar right-handed helical conformation. Increasing the pH leads to a more planar conformation of the backbone and aggregation of the polymer chains. 

It is known that [3.3]paracyclophane, which has the almost highest transannular interaction of the less distorted benzenes (12), has the fluorescence emission at longer wavelength (356 nm) (18) than the excimer of 1,3-diphenylpropane (332 nm). The fluorescence spectrum of the cyclopolymer, poly(St-C3-St), recorded under the same conditions as for [3.3]paracyclophane is illustrated in Figure 1 (20). Both have the fluorescence at the same wavelength, and therefore the polymer is supported to contain [3.3]paracyclophane units as sequence units. The fluorescence emission at 312 nm is ascribed to the residual styryl groups. 

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