PTX-PEG-Cy3 (Paclitaxel-PEG-Cy3) is a Cy3 labeled PTX-PEG conjugate. The Cy3 fluorophore is commonly used in applications such as immunolabeling, nucleic acid labeling, fluorescence microscopy, and flow cytometry. Cy3 has an emission maximum around 562-570 nm. PTX stabilizes tubulin polymerization. PTX can cause both mitotic arrest and apoptotic cell death. PTX also induces autophagy.