The quality of our proteins are monitored mainly by SDS-PAGE:
Our proteins are purified greater than 95% homogeneous and contain no detectable protease, DNase, and RNase activity.

To checked Proteins activity, here at ProteinOne, we used among other:
Our patent pending Active Protein Array, to check protein-protein / protein-DNA / protein-RNA... binding activity.

The in vitro transcription assay developed in-house to check transcription activity.