The N-isopropylacrylamide and acrylic acid copolymerlc microgel was prepared by dispersion polymerization The complex of micmgel containing terbium (Ⅲ) was prepared and characterized by dynamic laser scaRering(DLS)

UV spectrum

FT-IR and Fluorescence spectrum．The DLS results indicated that the particle radium decreased from 120 nm to 90 nm after the terbium adding into microgel．In the UV spectrum

the main absorption peak was red shifted from 204 nm to 210 nm

correspondingly

the peaks of carbonyl groups and the amino groups of the microgel also underwent a red shift in FT-IR spectrum by adding terbium (Ⅲ) ions．The above measurements indicated that the terbium ion could bind with the oxygen atom in carbonyl groups and the nitrigen atom in amino groups of microgel．The fluorescence spectrum showed that the Tb(Ⅲ)-microgel complex possesed a good fluorescence properties showing the characteristic emissions of terbium(Ⅲ) ions and the complex exhibited the strongest fluorescence emission at 0.6％ ration．