Intracellular distribution and mechanisms of actions of photosensitizer Zinc(II)-phthalocyanine solubilized in Cremophor EL against human hepatocellular carcinoma HepG2 cells

► The solubility of ZnPc was improved by using a Cremophor EL formulation. ► ZnPc mainly accumulated in mitochondria, lysosome and endoplasmic reticulum (ER). ► ZnPc triggered caspase-dependent apoptosis by elevating the intracellular ROS level. ► ZnPc induced cell cycle arrest in G2/M phase and decreased membrane potential (ΔΨm) in HepG2 cells.