Injectable drug delivery system based on in situ self-assembly of liquid star polyethylene glycol–poly(lactic-co-glycolic acid)

Particulate systems are widely used in biomedical applications, yet current systems are limited by their stability, complicated production processes, and the use of toxic excipients and cosolvents. Here, a new concept for an injectable nanocarrier system based on the in situ self-assembled star polyethylene glycol (PEG)– poly(lactic-co-glycolic acid) (PLGA)/drug mixture is presented. The new injectable material is based on a neat (solvent-free) liquid copolymer that self-assembles after it is injected along with the drug to form a particulate delivery system. The nanocarriers’ formation rate and encapsulation capabilities of hydrophobic drugs can be fine-tuned by changing the molecular weight of the PLGA segment. Furthermore, the starPEG–PLGA-based system demonstrates potential as a drug carrier for hydrophobic drugs and shows biocompatibility with cell line culture.