Real-time I-PCR has emerged as the
most sensitive assay for the detection of protein targets.
Sims et al. (2000) were the first researchers to use real-time
I-PCR for the detection of vascular endothelial growth
factor within human and mouse sera. In contrast to the
high sensitivities reported from the other laboratories, no
further increase in ELISA sensitivity was observed by these
researchers, probably due to matrix effects attributed to
non-specific binding of serum constituents that increased
the background noise and hence influenced the performance
of the I-PCR.