Studies On The Delivery System Of Amonafide

Amonafide?Amo?is a naphthalene antitumor compound that earliestly applied to the clinical research,which advances good curative effect for mammary cancer,leukemia and so on.As a chemotherapy drug,it hascertain side effects on human bone marrow;in the body it is vulnerable to form N-Acetyl-Amonafide acetylation by NAT2 that produce the side effects of and bone marrow inhibition uncertain side effects related to its metabolism,to make it stay in the third phase of clinical research at present.We imagine that the building of delivery system of Amo,it is a controlled-release biodegradable nanoparticles that overcome the side effects of metabolism,and decrease the times of taking medicine and make beneficial exploration for its clinical application.This paper optimized the synthesis of Amo,constructed Amo nanoparticles?NP?with poly?L-lactic-co-glycolic acid??PLGA?as the vehicle,studed the preparation,characterization,drug release properties,and inhibitory effect of a variety of tumor cells in vitro.Amo PLGA-NP were produced by nanoprecipitation method.The drug loading?DL?and incorporation efficiency were detected by ultraviolet spectrophotometry.The optimal preparation parameters were selected by singe factor and orthogonal-designing test.The shape and structure of the best preparation of nanoparticles was characterized by infrared spectrum and transmission electron microscope.The release characteristics of Amo NP was investigated by dialysis method that used to simulate thebody environment.The cell growth inhibition rate and mechanical of action was researched by MTT assay,contrast microscope,fluorescence microscopy and flow cytometry.The synthesis method of high purity?99.3%?and yield?76.3%?.FTIR shows that Amo-PLGA-NP contains weak?compressed?heavy aromatic group(1500-1700cm^-1)of Amo.The characteristics of the peak can indirectly show that Amo has successfully wrapped in Amo-PLGA-NP.Amo-PLGA-NP were spherical in shape and the average size was about 35.5 nm by TEM.The mean drug loading of Amo-PLGA-NP was?1.945±0.031?%and the mean encapsulation efficiency was?79.325±0.287?%.In vitro release profiles of Amo from the nanoparticles were obtained by a dissolution test in Tris-HCl buffer solution?Tris,1%DMSO,pH7.4?.The releasing test in vitro showed that over 98 percent of Amo encapsulated in Amo-PLGA-NP was continuously released in about 80 hour,with a burst release?29.32±0.89?%in the first2 hour.The cytotoxicity of Amo-PLGA-NP was investigated on three cancer cells of mammary cancer?MCF-7?cell,liver cancer?A549?cell and ovarian cancer?HeLa?cell.MTT test displayed that the mean cell growth suppression rate of blank nanoparticles was?1.58±0.64?%.The cancer cell growth inhibition rate was not made difference to blank-NP,but the released Amo from Amo-PLGA-NP;co-culture of MCF-7 and A549 cells showed that the cell growth inhibition rate of Amo-PLGA-NP was higher than that of free Amo?p<0.05?when the time was 12h,24h and 48h;co-culture of HeLa cells displayed that the cell growth inhibition rate of Amo-PLGA-NP was higher than that of free Amo?p<0.05?when 6h,12h,24h and48h;while co-culture of three kinds of cells showed that the cell growth inhibition rate of Amo-PLGA-NP and free Amo had no significant difference?p>0.05?when72h.Co-culture of three kinds of cells with Amo-PLGA-NP and free Amo showed that the cells with Amo-PLGA-NP were extremely spreaded with weak cell adhesion,disappear ed antenna,cytoplasmic condensation and even death by contrast microscopy.The cellular uptake of nanoparticles was showed by fluorescence microscopy with green fluorescence under the blue excitation light.Flow cytometry showed that fluorescence intensity under three kinds of cells incubated with Amo-PLGA-NP was stronger than that of incubated with free drugAmo-PLGA-NP had good stability small size with sustained release of Amo drugs.Amo-PLGA-NP can be swallowed by a variety of cancer cells and showed more significant effects in inhibiting the growth of cells than the free Amo did.Amo-PLGA-NP is a effective method to reduce the toxicity,it deserves further research.