[Spectra studies on the interaction of Mn2+ and poly N-isopropylacrylamide].

The interaction of Mn2+ and poly (N-isopropylacrylamide) (PNIPAAm) was studied by using UV-Vis, FTIR and fluorescence spectroscopic methods. The results indicated that Mn2+ could be bonded to oxygen atoms of carbonyl in PNIPAAm and form the complex of Mn2+ -PNIPAAm. It was found that there existed efficient Förster energy transfer from Mn2+ to PNIPAAm due to the emission spectra of Mn2+ overlapping the excitation spectra of PNIPAAm and that the emission peak of Mn2+ at 561 nm disappeared in Mn2+ -PNIPAAm complex. Therefore the fluorescence intensity at 307 nm was increased by 314%.