The fluorescence of the reporter portion of a NanoFlare is quenched in the absence of the target mRNA (left). In the presence of the target transcript, the fluorophore-conjugated oligonucleotide is released producing a fluorescent signal (right). The target mRNA competes with the fluorophore-coupled nucleic acid for the recognition sequence attached to the gold nanoparticle. Credit: Nanobrien [CC BY-SA 3.0 (https://creativecommons.org/licenses/by-sa/3.0)], from Wikimedia Commons
Read about using NanoFlares to detect the cells that cause excessive scarring:
N. R. Gough, Scar-Detecting Nanoparticles. BioSerendipity (9 May 2018) https://www.bioserendipity.com/scar-detecting-nanoparticles/