MMP14 and neuroblastoma: This nanoprobe utilized Near Infrared (NIR)-II-emitting Ag2S quantum dots with (a) PEGylated AF7P, a peptide targeting MMP-14 loop domain in neuroblastoma to allow for primary localization and (b) NIR-II absorbing A1094 poly-anionic fragments (E8) conjugated to MMP-14 activated peptide, which conceals R9 cell penetrating peptide (TAT) prior to activation [253].