Synthesis of Inherently Fluorescent Core-Shell Nanoparticles for Cell Imaging and Targeting Therapy: An In Vitro Evaluation

Fluorescent polymer nanoparticles (NPs) have great potential as bioimaging and therapeutic agents in the biomedical field. Here, a subtle method is developed to synthesize inherently fluorescent core-shell NPs with diameters less than 100 nm. The permanent fluorescence comes from the rigid conjugated structure between benzene and chloromethyl groups in the crosslinked poly(chloromethylstyrene) (PCMSt) core, which is able to be applied for the determination of Fe3+ with a detection limit of 1.39 x 10(-6) m. It is further demonstrated that the galactose modification (poly (6-O-acryloyl-d-galactose), PADGal) shell can efficiently center dot facilitate the selective internalization of NPs by human hepatocellular carcinoma cells (HepG2), and the cells are more prone to uptake the NPs with medium crosslinking degree. The hydrophobic anticancer drug 10-hydroxycamptothecin (HCPT) is then loaded onto PADGal@PCMSt NPs. Benefiting from the specific interactions between asialoglycoprotein (ASGP) receptors and the galactose moiety, the PADGal@PCMSt NPs can deliver HCPT with the highest efficiency to HepG2 cells in comparison with the human cervical cancer cells (HeLa), the human alveolar adenocarcinoma basal epithelial cells (A549), the mouse breast cancer cells (4T1), and the mouse fibroblast cells (NIH3T3). The present study provides a new strategy to build small-size fluorescent polymer NPs with both bioimaging and therapeutic functions.