Functional v Competitive PPIase Assay

The table below describes, using the example of cyclophilins, the main differences between the functional and competitive PPIase assays available at Selcia. The functional PPIase assay is usually used for detailed kinetic measurement of known inhibitors. The competitive binding TR-FRET assay is usually used to confirm whether your inhibitor is competitive with cyclosporine A and for screening of a larger number of unknown inhibitors.

Comparison of Selcia’s Cyclophilin Assays

Criteria Functional PPIase Assay Competitive TR-FRET Assay1
Assay type functional competitive binding
Throughput single cuvette 384 well
Detection 330nm FRET (ratio of two wavelengths)
Deliverable Ki value Kd value
Lower sensitivity Ki>1nM Kd>5nM
Turnaround time 2-3 weeks (2) 1-2 weeks (2)
  1. 384 well competitive binding time-resolved fluorescence resonance energy transfer assay
  2. Typical time for dose response curves of 12 compounds