PCL(4k)-PEG(1k)-FITC is a block copolymer with polycaprolactone (PCL) as hydrophobic and PEG as hydrophilic block. The polymer contains green fluorescent dye which can be easily traced by fluorescence microscopy. In water, the polymer self-assembles with PCL being shielded from water by the PEG. The core region can serve as hydrophobic drugs reservoir. Reagent grade, for research purpose.