Fluorescence studies of volume phase transition in polyacrylamide gels with a pyrenyl probe in acetone/water mixed solvent

Abstract

The change in microenvironments and dynamics of poly(acrylamide) (PAAm) gels during the volume phase transition induced by the change in acetone content in an acetone/water mixed solvent were studied by measuring the fluorescence spectra, lifetime, and rotational diffusion coefficient of a prenyl probe attached to the side chain of the PAAm gels. The linear and cross-linked copolymers of acrylamide and sodium methacrylate were used. The results are (a) the volume phase transition of the PAAm gels from the swollen to collapsed state is accompanied by increases in interaction between PAAm main chains and the hydrophobicity of the microenvironment