Investigation of endocytosis and cytotoxicity of poly-d, l-lactide-poly(ethylene glycol) micro/nano-particles in osteoblast cells.
Biodegradable polymer particles present a promising approach for intracellular delivery of drugs, proteins, and nucleic acids. Poly-d,l-lactide-poly(ethylene glycol) (PELA) copolymers with different weight ratios of polyethylene glycol (PEG) were used as drug carriers in the present study. PELA particles entrapped with fluorescein isothiocyanate (FITC) as a fluorescent marker were formulated using a double emulsion-solvent evaporation technique. The size and morphology of the particles were observed with scanning electron microscope (SEM), atomic force microscope (AFM), and laser diffraction particle size analyzer (LDPSA). The purpose in the present work was to investigate the cytotoxicity and the process of endocytosis of PELA particles with different contents of PEG and variable particle size using rat osteoblasts (OBs). The cytotoxicity of the particles was investigated using 5-dimethylthiazol-2-yl-2,5-diphenyltetrazolium bromide (MTT) assay and flow cytometry. Results indicate that as the content of PEG in the polymer increased, so did cell survival. Endocytosis was observed through a light microscope and a fluorescence microscope; intracellular uptake and retention were determined quantitatively using fluorescence spectrophotometer (FSP). The results showed that as PEG content in PELA copolymer increased, there was a reduction in endocytosis of nanoparticles in osteoblasts.
School of Materials Science and Engineering, Key Laboratory of Advanced Technologies of Material, Ministry of Education, Southwest Jiaotong University, Chengdou, Sichuan, People's Republic of China.
Weijia
W
Wang
Shaobing
S
Zhou
Laiyang
L
Guo
Wei
W
Zhi
Xiaohong
X
Li
Jie
J
Weng
D000818:Animals; D002470:Cell Survival / Q000187:drug effects; D002478:Cells, Cultured; D004337:Drug Carriers; D016503:Drug Delivery Systems; D004705:Endocytosis; D008422:Materials Testing; D018625:Microscopy, Atomic Force; D046529:Microscopy, Electron, Transmission; D008856:Microscopy, Fluorescence; D008863:Microspheres; D050997:Nanomedicine; D054118:Nanospheres / Q000737:chemistry* / Q000633:toxicity* / Q000648:ultrastructure; D010006:Osteoblasts / Q000187:drug effects* / Q000502:physiology*; D010316:Particle Size; D011091:Polyesters / Q000737:chemistry* / Q000378:metabolism / Q000633:toxicity*; D011092:Polyethylene Glycols / Q000737:chemistry* / Q000378:metabolism / Q000633:toxicity*; D051381:Rats
D004337:Drug Carriers; D011091:Polyesters; D011092:Polyethylene Glycols; C083464:poly(ethyleneglycol-lactide)