ABSTRACT
OBJECTIVE To prepare anemoside B4 （AB4） and programmed cell death ligand 1 （PDL1） siRNA （siP） co- delivered cRGD-modified targeting liposomes （AB4/siP-c-L）， and to study the cellular uptake in vitro. METHODS The cRGD- modified AB4-loaded targeted liposomes （AB4-c-L） were prepared by ethanol injection. AB4-c-L was mixed with 20 nmol/L siP in the same volume and AB4/siP-c-L was obtained through electrostatic adsorption. The particle size， Zeta potential， morphology， encapsulation efficiency and drug content， in vitro release behavior and serum stability of AB4/siP-c-L were investigated by laser scattering particle size tester， transmission electron microscopy， ultrafiltration centrifugation， dialysis and agar-gel electrophoresis block test. Cellular uptake of AB4/siP-c-L by Lewis lung cancer cells LLC and its intracellular localization were evaluated by flow cytometry and confocal laser scan technique. RESULTS The average particle size of AB4/siP-c-L was （187.4±3.1） nm， and the Zeta potential was （33.5±1.4） mV. AB4/siP-c-L was spheroidal in shape. The encapsulation efficiency and content of AB4 were （95.2±0.4） % and （1.0±0.2） mg/mL， respectively. AB4/siP-c-L could better package siP， and exhibited good serum stability， obvious pH sensitivity and sustained release property. The uptake rate of AB4/siP-c-L by LLC cells was significantly higher than that of free drug， and was able to accumulate in cytoplasm. CONCLUSIONS AB4/siP-c-L can effectively realize the co-loading of AB4 and gene drug siP， which has certain in vitro targeting to LLC cells.