The 9-mer peptide ICG-Glu-Glu-AE105 also targets the uPAR-ATF interaction with a KD of 134 × 10−9 M and results in rapid (6–24 h) tumor localization in various in vivo xenograft models [47–49].While the delayed imaging window of uIgG-800F and rapid imaging window of ATF peptides and ICG-Glu-Glu-AE105 are evident, peak fluorescence is much harder to compare as these constructs not only differ in size and affinity but also in fluorophore. This evidence concerns the gene PLAUR and neoplasm.