Detection of 6-His-tagged Protein by Western Blot.  Samples: 200, 100, or 50 ng of E. coli whole cell lysate expressing a multi-tag fusion protein.   Antibodies: Affinity purified, rabbit anti-6-His antibody A190-214A used for WB at 0.04 ug/ml (1:25,000). Detection: Chemiluminescence with an exposure time of 3 seconds.