Provided is an activatable probe that undergoes intramolecular cyclization and subsequent aggregation in apoptotic tumor cells upon peptidase-initiated, and most advantageously caspase-3, activation. These caspase-sensitive nano-aggregation probes (C-SNAFs) are generally biocompatible, possess NIR spectral properties or may serve as PET or MRI imaging agents, and have a mechanism of target-mediated nanostructure self-assembly amenable to in vivo use. The probes encompass biocompatible condensation chemistry products that comprise D-cysteine and 2-cyano-6-hydroxyquinoline (CHQ) moieties linked to an amino-luciferin scaffold, and which can be activated by a two-step reaction requiring caspase-3/7-mediated cleavage of an aspartate-glutamate-valine-aspartate (L-DEVD) capping peptide and the free intracellular thiol-mediated reduction of the disulfide bond.
提供的是一种可激活的探针,当肽酶引发并且最好是caspase-3引发时,在凋亡肿瘤细胞中会发生分子内环化和随后的聚集。这些caspase敏感的纳米聚集探针(C-SNAFs)通常具有
生物相容性,具有近红外光谱特性或可用作PET或MRI成像剂,并且具有适于体内使用的靶向介导的纳米结构自组装机制。这些探针包括
生物相容性凝聚
化学产物,其中包括
D-半胱氨酸和2-
氰基-
6-羟基喹啉(CHQ)基团连接到
氨基-路西非林支架上,并且可以通过两步反应被激活,需要caspase-3/7介导的
天冬氨酸-谷
氨酸-缬
氨酸-
天冬氨酸(L-DEVD)覆盖肽的剪切和游离细胞内
硫醇介导的二
硫键还原。