1,2-distearoyl-rac-glycerol PEG2000 fluorescein (DSG-PEG2000-FITC) is a diacyl glycerol lipid fluorescein conjugate that contains no phosphate linkage. Stearic acid is a saturated C18 lipid that can interact well with cell membrane bilayer. Fluorescein modified distearoyl glycerol has strong green fluorescence with exitation/emission at 494 nm/515 nm. PEG linker between distearoyl glycerol and fluorescein offers better water solubility and flexible linker structure. DSG-PEG-fluorescein thus can be an excellent membrane imaging agent.