Recent Progress on Lysosome-Targetable Fluorescent Probes

Lysosomes are vital in many physiological processes such as metabolism, membrane repair, cell apoptosis, etc. To have lysosomes visualized and reactive small molecules (RSMs) detected are of great significance on the understanding of some intracellular dynamic procedures as well as the therapy of related deseases. In the past few years, many lysosome-targeting RSMs-sensing fluorescent probes are reported, including protons, reduction species, oxidation species, metal cations, anions, enzymes and some physical properties such as pH, viscosity and temperature. The mechanism of targeting lysosomes can be classified into three types: (1) based on the acidic physiological environments in lysosomes, (2) based on the pathway of substance metabolism, especially the endocytosis of materials, and (3) based on the specific membrane proteins and hydrolases in lysosomes. The recently reported lysosomal fluorescent probes were assorted, summarized and reviewed in this work. The bright prospects of these probes in the application of preliminary diagnosis and therapy of some diseases were also discussed.