PCL(3k)-PEG(3k)-RhB is a micelle-forming biodegradable polymer with red fluorescent probe for staining and labeling. The polymer is amphiphilic due to the presence of hydrophobic polycaprolactone (PCL) and hydrophilic PEG blocks. The micelles formation can be used as nanocarrier where the hydrophobic regions, shielded from water, serve as reservoirs for hydrophobic drugs. Reagent grade, for research purpose.