Clodronate liposomes are composed of chlorophosphate salts encapsulated within phospholipid bilayer liposomes, which are selectively ingested by macrophages following systemic administration. Within macrophage lysosomes, phosphatases gradually release the chlorophosphate salts from the liposomal vesicles, leading to their intracellular accumulation. Once a threshold concentration is reached, the accumulation results in irreversible damage to the macrophages and induces apoptosis, making clodronate liposomes a useful research tool for investigating macrophage depletion and immune modulation.