Hydrophobically associating copolymers fluorescence

Hydrophobic associations in random copolymers of AMPS and iV-d ecylmethacrylamide (DodMAm) were investigated by viscometry, QELS, capillary electrophoresis (CE), NMR relaxation, and various fluorescence techniques (24,48), For fluorescence studies, the polymers that are singly-labeled with pyrene or naphthalene or doubly-labeled with pyrene and naphthalene (Chart 2) were employed (48). In this section, the self-association behavior of AMPS-DodMAm co lymers in water will be discussed with a focus on intra- and interpolymer self-associations as a function of the DodMAm content (/bod) in Ae copolymer. 

Analysis of the fluorescence decay curves in water indicated that the intracoil process is static and that anthryl aggregation induces non-exponentiality in the fluorescence decay associated with a dynamic equilibrium between the singlet diphenyl-anthracene and a non-fluorescent dimer state. Further evidence was also presented to show that these polymers self-organise into hydrophobic and hydrophilic regions Energy migration in alternative and random copolymers of 2-vinylnaphthalene and methyl methacrylat methacrylic acid... 

The observed release pattern from both types of microspheres lies in the distribution of the protein inside a microsphere, which is associated with the preparation method. In order to see this, FITC (fluorescein isothiocyanate)-insulin incorporated microspheres were observed under a confocal microscope, as shown in Fig. 7. For Msp A, a homogeneous distribution of fluorescence was observed while Msp B exhibited a rather heterogeneous distribution of FITC-insulin. In addition, Msp B shows significant surface fluorescence. These observations are, hence, consistent with the observed initial burst from Msp B and from the constant insulin release from Msp A over a prolonged period of time. It is reported that the constant release of insulin from triblock copolymer hydrogel may be attributed to the hydrophilic/hydrophobic domain structure of the gel. The incorporation of a significant fraction of insulin in the hydrophobic domain may have made possible... 

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