PEG–lipid–PLGA hybrid nanoparticles loaded with berberine–phospholipid complex to facilitate the oral delivery efficiency

The natural product berberine (BBR), present in various plants, arouses great interests because of its numerous pharmacological effects. However, the further development and application of BBR had been hampered by its poor oral bioavailability. In this work, we report on polymer–lipid hybrid nanoparticles (PEG–lipid–PLGA NPs) loaded with BBR phospholipid complex using a solvent evaporation method for enhancing the oral BBR efficiency. The advantage of this new drug delivery system is that the BBR–soybean phosphatidylcholine complex (BBR–SPC) could be used to enhance the liposolubility of BBR and improve the affinity with the biodegradable polymer to increase the drug-loading capacity and controlled/sustained release. The entrapment efficiency of the PEG–lipid–PLGA NPs/BBR–SPC was observed to approach approximately 89% which is more than 2.4 times compared with that of the PEG–lipid–PLGA NPs/BBR. To the best of our knowledge, this is the first report on using polymer material for effective encapsulation of BBR to improve its oral bioavailability. The prepared BBR delivery systems demonstrated a uniform spherical shape, a well-dispersed core-shell structure and a small particle size (149.6 ± 5.1 nm). The crystallographic and thermal analysis has indicated that the BBR dispersed in the PEG–lipid–PLGA NPs matrix is in an amorphous form. More importantly, the enhancement in the oral relative bioavailability of the PEG–lipid–PLGA NPs/BBR–SPC was ∼343% compared with that of BBR. These positive results demonstrated that PEG–lipid–PLGA NPs/BBR–SPC may have the potential for facilitating the oral drug delivery of BBR.