Fluorescence of poly

Fluorescence of poly(phenylsilane) at room temperature was not detected. Poly(chlorophenylsilane) has a long wavelength tail out to 380 nm with a transition centered at 330 nm. Substitution of the Si-Cl bonds of the... 

It was also found in the CPF spectra that no circular polarization was detected in the monomer fluorescence of poly(l- and 2-napAla)s. This indicates that the lowest-energy excited state of the naphthyl polymers is virtually localized on a monomeric naphthyl group and not delocalized over neighboring chromophores to form an exciton state. 

Figure 1. Effect of variation in temperature on polarization of fluorescence of poly Glu Lys2,1 (No. 3) conjugated with DNS or fluorescein (48)...

As a medical application of poly(ADP-ribose) immunofluorescence, Ikai et al. reported that myeloblasts in peripheral blood as well as in bone marrow in patients with acute myeloblastic leukemia (AML) showed intense fluorescence of poly(ADP-ribose) in nuclei and that this was the case for blastic crisis of chronic myelocytic leukemia (CML)[13]. 

A fluorometric detection of oligonucleotide hybridization is also possible since the fluorescence of poly(3-alkoxy-4-methylthiophene)s is quenched in the... 

The experimental method to assess the phase behavior is to measure the ratio of excimer to monomer intensity, la/lm- Samples of the polymer blend are cast on sapphire disks at thicknesses of the order to 10-25 pm, and the fluorescence spectra are obtained. In a study of the excimer fluorescence of poly(2-vinyl naphthalene) (P2VN) in polystyrene, the monomer emission peak at 337 nm was compared with the excimer emission peak at 398 nm [334]. The ratio of the peaks versus polystyrene molecular weight is illustrated in Fig. 5.32 (a and b). Phase separation (at 0.3 wt% P2VN addition) was observed at PS Mn of 17,500. It was noted that the results show the onset of phase separation before any visual phase separation was observed. 

Fluorescence and phosphorescence spectra of poly(propynoic acid)(FPA), polyphenylene (PP), and DPAcN show that the difference of energies between the lower excited singlet and triplet states, as observed in the case of PP (583 nm) and DPAcN (528 nm), is considerably greater than that of poly(propynoic acid) (270—300 nm) which besides transitions may undergo rr - transitions. PCSs showing only... 

It has been demonstrated that dendrimers can be used also as fluorescent sensors for metal ions. Poly(propylene amine) dendrimers functionalized with dansyl units at the periphery like 34 can coordinate metal ions by the aliphatic amine units contained in the interior of the dendrimer [80]. The advantage of a dendrimer for this kind of application is related to the fact that a single analyte can interact with a great number of fluorescent units, which results in signal amplification. For example, when a Co ion enters dendrimer 34, the fluorescence of all the 32 dansyl units is quenched with a 32-fold increase in sensitivity with respect to a normal dansyl sensor. This concept is illustrated in Fig. 3. 

Aoki, H., Kitamura, M. and Ito, S. (2008) Nanosecond dynamics of poly(methyl methacrylate) brushes in solvents studied by fluorescence depolarization method. Macromolecules, 41, 285-287. 

In order to develop compounds that can selectively target duplex RNA, Sinha et al. [ 194] studied the interaction of berberine with two different conformations of poly(rC) poly(rG) structures. Poly(rC) poly(rG) has been shown [15,215] to exist in two conformations depending on the pH of the solution, the A-form at physiological pH and the protonated form at pH 4.3. These two conformations have been characterized to have clearly defined but distinctly different circular dichroic and absorption spectral characteristics. Both the A-form and the protonated form of the RNA induced moderate hypochromic change and bathochromic shifts in the absorption maxima peaks at 344 nm and 420 nm of the alkaloid with three isosbestic points centered around 357,382 and 448 nm. Binding of berberine to both forms enhanced the fluorescence intensity, which was higher with the protonated form than with the A-from, suggesting clear differences in the nature of orientation... 

The fluorescence of the l>ylJ-containing probe ((pODN 5 -d(GGGCGGGTTTT TTTTTTCCC l>ylJ CCCTTTTTTTTTT)-3 )) was quenched in the absence of poly... 

Fluorescent pseudomonads are capable of synthesizing poly(3HAMCL)s from a large number of substrates. Work on the biotechnological production of poly(3HAMCL) has focused mainly on two model systems - Pseudomonas oleo-vorans and P. putida. P. oleovorans is able to use alkanes and alkenes as substrate due to the presence of the OCT-plasmid while P. putida, which does not have this plasmid, cannot. In contrast to P. oleovorans, however, P. putida can use carbohydrates such as glucose and fructose for the production of poly(3HAMCL). 

Jiang and Zhu (2001) reported on the synthesis of poly(p-carboxyphe-noxy succinic monoester anhydride) and poly(p-carboxyphenoxy adipic monoester anhydride) (PCPSM and PCPAM), and the copolymer P(CPAM-CPSM) as polymeric antimicrobial prodrugs for diseases such as malaria and hepatitis B. They also reported that PCPSM exhibits strong fluorescence, the intensity of which increases linearly with its molecular weight (Jiang et al., 2001a,b). They showed that when co-polymerized the fluorescence is maintained, though diminished approximately in proportion to the copolymer composition. 

Jiang and Zhu (2001) became interested in synthesizing additional polyanhydrides with fluorescence after their discovery of the fluorescent properties of PCPS. They synthesized the series of poly(anhydride-co-amide)s poly p-[carboxyphenoxy(ethyl/propyl/butyl)formamido]benzoic anhydride (PCEFB, PCPFB, and PCBFB) (Jiang et al., 2001c). Only the ethyl polymer emitted strong fluorescence, which was consistent with their previous study of the poly(anhydride-co-ester)s of similar chemistry... 

Kinetics with positive and negative amplitudes were observed for the natural ml-DNA and bm-DNA samples binding to 5.119 The kinetics were monitored by the fluorescence of 5 and the emission quantum yield for 5 bound to GC sites was much lower than for 5 bound to AT sites. The positive amplitudes were related to relocation of 5 from GC sites to AT sites. The different kinetics observed for ml-DNA compared with bm-DNA are in line with the observation that the binding dynamics of 5 with poly[d(G-C)] and poly[d(A-T)] were very different. 

By fluorescence analyses just upon laser ablation and of ablated surface, Molecular aspects of ablation echanisa were elucidated and a characterization of ablated Materials was perforaed. Laser fluence dependence of poly(N-vinylcarbazole) fluorescence indicates the iaportance of Mutual interactions between excited singlet states. As the fluence was increased, a plasna-like eaission was also observed, and then fluorescence due to diatonic radicals was superinposed. While the polyner fluorescence disappeared Mostly during the pulse width, the radicals attained the naxinun intensity at 100 ns after irradiation. Fluorescence spectra and their rise as well as decay curves of ablated surface and its nearby area were affected to a great extent by ablation. This phenonenon was clarified by probing fluorescence under a Microscope. 

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... 

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