Based on the same principle, fluorescent BRS-680 was developed as an optical alternative for preclinical imaging of cancer, using a 7-amino acid sequence from GRP that was labeled with a NIR fluorophore (ex/em 674/690 nm) and conjugated with a pharmacokinetic modifier to improve its bioavailability and circulation half-life (plasma t1/2 ~ 1.7h). The gene discussed is GRP; the disease is cancer.