Abstract: The objective of this study is to purify μ-Calpain from cattle spleen by applying a variety of biological methods and different procedures. Fresh yellow cattle spleen (within 30min postmortem) was sampled and treated with procedures such as homogenization, ionic exchange, hydrophobic chromatography, molecular sieve exclusion etc. In the last step, the specific activity of resultant μ-Calpain was 38.4U/mg. Meanwhile, the total activity and specific activity of μ-Calpain and other parameters related at different major purification procedures were detected and verified by way of SDS-PAGE and casein zymography.

Key words: &mu, -Calpain； purification； column chromatography； casein-zymography； SDS-PAGE；