Vitamin E-loaded polymeric nanoparticles from biocompatible adipate-based copolymer obtained using the nanoprecipitation method

Despite the search for new biomaterials dedicated for biomedical applications intensified in recent decades, this field is still not fully explored. Therefore, the synthesis of novel aliphatic biopolyesters poly(butylene adipate-co-dilinoleic adipate) (PBA-DLA) was performed using monomers derived from natural sources and enzyme lipase B Candida antarctica (CALB) as biocatalyst in order to provide fully biobased and biodegradable material suitable for drug delivery systems. Proton nuclear magnetic spectroscopy (1H NMR) analysis confirmed chemical structure of PBA-DLA copolyester whereas in vitro cytotoxicity assay indicate on material biocompatibility. By applying a single-step nanoprecipitation method narrowly distributed PBA-DLA nanoparticles (NPs) with hydrodynamic diameter (HD) of ~200 nm were produced, however, after purification (centrifugation) step NPs tend to agglomerate. In order to eliminate this drawback suitable amount of stabilizer (Pluronic F127, 0.05 mg/ml) was selected and NPs with HD of ~149 nm were obtained. The PBA-DLA NPs could be loaded with the hydrophobic α-tocopherol (α-TP) – main ingredient of vitamin E, with encapsulation efficiency ranging from 48 to 74 % depending on tested α-TP concentration (2.5, 5, 10 mg/ml) as evidenced by combined dynamic light scattering (DLS), ultraviolet-visible spectroscopy (UV-VIS) and 1H NMR measurements.