Abstract: The freshwater crabs(Sinopotamon henanense) were exposed with 100 mg/L Cu(as CuSO4·5H2O) to induce synthesizing of metallothionein(MT).Then the crabs were dissected and the hepatopancreas were taken out,homogenized and centrifugalized.The supernatant obtained were purified primarily using acetone precipitation(50 %～80 %),followed by chromatography treatment on columns Sephadex G-50 and DEAE sepharose fast flow,then dialyzed to desalt.According to SDS-PAGE analysis,UV absorbance spectrometry analysis and mass spectrometry analysis,high purity MT is obtained,and its molecular weight is 6882 D.

Key words: copper, Sinopotamon henanense, metallothionein, isolation and purification