Excerpt -- A sensible approach to improve quenching efficiency is to preserve the terminal quencher for its blocking function while incorporating a second quencher at an internal position. That is the basis of novel double-quenched probe-type from LGC Biosearch Technologies, called BHQnova™ Probes:
5’ - [FAM]- Oligo sequence1 - [Nova] - Oligo sequence2 - [BHQ-1] - 3’
Standard hydrolysis probe vs BHQnova probes
Figure 1. qPCR amplification curves for BHQnova Probes (red) demonstrate the improved quenching and S:N of BHQnova Probe vs. standard hydrolysis probe (black) of the same sequence.