Photophysics of Laser Dyes in Aqueous Polymer Media
Final technical rept.,
BOSTON UNIV MA DEPT OF CHEMISTRY
Pagination or Media Count:
The photophysical properties of a series of coumarin laser dyes in an aqueous polyelectrolyte medium have been measured. The binding of the dyes to polymethacrylic acid PMAA in water has been demonstrated through the observation of dramatic blue-shifts of fluorescence bands and increases in emission quantum yield and lifetime and polarization. The systematic changes in fluorescence properties reveal that the hydrophobic dyes reside in relatively nonpolar dry and highly viscous microdomains at lower pH values for aqueous PMAA solutions in which a highly compact conformation of the uncharged polyelectrolyte is important. The transition from the hypercoiled conformation pH 4-8 can be followed readily by reference to coumarin fluorescence wavelength, quantum yield and polarization data.
- Lasers and Masers