Phosphorescence Properties of 2-Amino- 1 -methyl-6-phenylimidazo[4,5- b]pyridine and Benzo[f]quinoline in Glucose Glasses via Temperature Variation and Spectral Characterization

摘要

Phosphorescence intensities and lifetimes of 2-ammo- 1-methyl-6-phenylimidazo[4,5-b]pyridine (PhIP) and benzo[f]quinoline (B[f]Q) in glucose glasses were measured over a wide range of temperatures. As the temperature decreased, both the phosphorescence lifetimes and the phosphorescence intensities for both PhIP and B[f]Q in glucose glasses increased. However, the phosphorescence intensity-to-lifetime ratio was not constant at different temperatures, which indicated that the triplet state formation efficiency was a function of temperature. Also, the in(1/τ↓(p) - 1/τ↓(p0)) vs 1/T plots for both PhIP and B[f]Q in glucose glasses with and without a heavy-atom salt gave nonlinear plots. From the plots for the samples with and without a heavy-atom salt, activation energies were obtained. The activation energies were related to low-frequency vibrational modes in the solid matrix, rotational relaxation of functional groups, and diffusion of water in the solid matrix. Infrared spectrometry revealed water in the glasses, and phosphorescence decay curves and confocal laser scanning microscopy showed the heterogeneity of the distribution of NaI in the glucose glasses.