Invited for this month's cover is the group of Prof. Jörg Eppinger. The cover picture illustrates the concept of using metal-conjugated affinity labels (m-ALs) to convert proteases into well-defined and catalytically active artificial metalloenzymes. For more details, see the Communication on p. 50 ff.

Immobilized Metal-Affinity Chromatography (IMAC) represents a relatively new separation technique that is primarily appropriate for the purification of proteins with natural surface-exposed histidine residues and for recombinant proteins with engineered histidine tags or histidine clusters. Because the method has gained broad popularity in recent years, the main recent developments in the field...

Protein-A or Protein-L affinity chromatography and virus inactivation are key processes for the manufacturing of therapeutic antibodies and antibody fragments. These two processes often involve exposure of therapeutic proteins to denaturing low pH conditions. Antibodies have been shown to undergo conformational changes at low pH, which can lead to irreversible damages on the final product. Here...

Affinity capillary electrophoresis has become an established approach for performing interaction studies. In affinity electrokinetic chromatography the retention factor, as in liquid chromatography, is useful for describing the migration behavior of the analytes, and is instrumental for assessing the affinity of an analyte for the pseudo-stationary phase. Erroneous use of the retention factor c...

The rates at which biological interactions occur can provide important information on the mechanism and behavior of such processes in living systems. This paper will discuss how affinity chromatography can be used as a tool to examine the kinetics of biological interactions. This approach, referred to here as biointeraction chromatography, uses a column with an immobilized binding agent to exam...