Affinity techniques thrombin

You have isolated a protein of interest tagged with the GST domain. At this point, the fusion protein is bound to the glutathione Sepharose 4B resin and the unbound proteins have been washed away. Describe, in detail, two different techniques that you could use to isolate the protein without the affinity tag using only thrombin, glutathione Sepharose 4B, and reduced glutathione. 

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