Study On The Preparation And Cellular Uptake Of Mitoxantrone-polylactic Acid Nanoparticles

In this paper, Mitoxantrone polylactic acid nanoparticles (DHAQ-PLA-NP) and the Dextran 70 coating DHAQ-PLA-NP were prepared. The aims are to enhance the therapeutic efficacy of mitoxantrone in treating, reduce the toxicity and increase the uptake amount. Then, the cytotoxicity of DHAQ and DHAQ-PLA-NP on human hepatoma cells (SMMC-7721) and human normal hepatocyte (LO2) were studied. Finally, the uptake of the original drug, DHAQ-PLA-NP and Dextran 70 coating DHAQ-PLA-NP in these two cells was investigated. The study will provide some available information for liver cancer treatment of DHAQ-PLA-NP in clinic.The method of precipitation was employed to prepare DHAQ-PLA-NP. The factors, such as the ratio of organic solvent and surfactant which influence the preparation were investigated, and the techniques were optimized. The size was about 150 nm; the PDI was between 0.1 to 0.3 and the zeta potential was about -40mv. DHAQ-PLA-NP lyophilization injection was prepared by using lactose as protective agent in freeze drying. The product was of good looks and good quality. The results showed that the embedding ratio and drug loading of the nanoparticles were high. The nanoparticles had the characteristic which was the size well-distributed, freeze-dried good effect and so on.To reduce the liver toxicity of normal cells and investigate the effect of DHAQ-PLA-NP to liver cancer chemotherapy, the MTT assay was carried out to measure the cytotoxicity of DHAQ and DHAQ-PLA-NP on human hepatoma cells SMMC-7721 and human normal hepatocyte LO2. The results showed that the killing effect of DHAQ and DHAQ-PLA-NP was time- and dose-dependent. It was found that the IC50 of nanoparticles which have slow-releasing property, at the same time, was greater than the IC50 of DHAQ. It was showed that DHAQ-PLA-NP could reduce the toxicity.Furthermore, in order to increase the uptake of DHAQ-PLA-NP on human hepatoma cells SMMC-7721 and compare the uptake of DHAQ-PLA-NP between human hepatoma cells SMMC-7721 and human normal hepatocyte LO2, Dextran 70 coating DHAQ-PLA-NP was used and the concentration of mitoxantrone in SMMC-7721 cells and LO2 cells was determined by HPLC and the content of protein in cells by BCA method. The results showed that there was no obvious difference between DHAQ and DHAQ-PLA-NP at lower concentration. However, the uptake amount of DHAQ-PLA-NP was much larger than that of DHAQ at higher concentration and the uptake amount of 2% Dextran 70 coating DHAQ-PLA-NP was the most. The uptake amout of DHAQ-PLA-NP was larger than that of DHAQ and the uptake amout of 2% Dextran 70 coating DHAQ-PLA-NP was also higher than that of DHAQ-PLA-NP (P<0.05). It was showed that the uptake of Dextran 70 coating DHAQ-PLA-NP was more easily by cells.