Facilitated self-assembly of novel dendron-based copolymers

Self-assembly of newly synthesized dendron-based amphiphilic copolymers with controlled hydrophilic-lipophilic balances has been investigated to evaluate their potential as a novel nanocarrier. The hydroxyl-terminated polyester dendron (G3) bearing a focal alkyne moiety was used to mediate the combination of poly(s-caprolactone) (PCL) with multiple polyethylene glycol (PEG) moieties. Four types of PCL-G3-mPEG with different block lengths were prepared and their structures were confirmed by ¹H NMR, FT-IR, and GPC. Critical micelle concentration (CMC) values varied from 6.50 × 10^-8 to 3.52 × 10^-7 M, which were lower than those reported for linear PCL-mPEG. TEM revealed that all PCL-G3-mPEG micelles were spherical with an average diameter of 20 nm. The drug release profile for each PCL-G3-mPEG was investigated by loading indomethacin (IMC), as a model drug, within the micelles. IMC was released in a controlled manner over 72 hours. Synthesized copolymers used in this study were also found to be non-cytotoxic at concentrations up to 100 μM. The low CMC, along with the controlled morphology, release profile and biocompatibility, all demonstrate the potential of the dendron-based micelles as a novel nanocarrier.