Novel Monomethoxy Poly(Ethylene Glycol) Modified Hydroxylated Tung Oil for Drug Delivery

Novel monomethoxy poly(ethylene glycol) ( PEG) modified hydroxylated tung oil (HTO), denoted as PEG-HTO- PEG, was designed and synthesized for drug delivery. PEG-HTO- PEG consists of a hydroxylated tung oil center joined by two PEG blocks via a urethane linkage. The properties of PEG-HTO- PEG were affected by the length of the mPEG chain. Three PEG with different molecular weights were used to prepare PEG-HTO- PEG. The obtained three PEG-HTO- PEG polymers were characterized by nuclear magnetic resonance (NMR), Fourier transformation infrared spectroscopy (FT-IR), differential scanning calorimetry (DSC) and gel permeation chromatography (GPC), respectively. Furthermore, the particle sizes of PEG-HTO- PEG micelles were evaluated by dynamic light scattering (DLS) and transmission electron microscope (TEM). A critical aggregation concentration (CAC) ranged from 7.28 to 11.73 mg/L depending on the chain length of mPEG. The drug loading and release behaviors of PEG-HTO- PEG were investigated using prednisone acetate as a model drug, and results indicated that hydrophobic prednisone acetate could be effectively loaded into PEG-HTO- PEG micelles and exhibited a long-term sustained release. Moreover, compared with HTO, PEG-HTO- PEG had no obvious cytotoxicity to HeLa and L929 cells. Therefore, monomethoxy poly(ethylene glycol) modified hydroxylated tung oil PEG-HTO- PEG may be a promising drug carrier.