Studies On Preparation And Antitumor Activity Of Adriamycin Magnetic Micelles Based On Starch-octanoic Acid Graft

Malignant tumor is a serious threat to human life and the quality of life,and drug therapy is still the most commonly treatment.Nanomicelle is a novel drug carrier and has been widely used in solubilising hydrophobic drug and maintaining the stability of drug efficacy.In this study,the magnetic nanoparticles and antitumor drug were both loaded into nanomicelle delivery system,as magnetic nanoparticles with the characteristics of response to the external magnetic field,the antitumor drug can be delivered to targeted parts with the use of external magnetic field,and the efficiency of drug was significantly increased,while the side effects of drugs to normal tissues also can be relieved.In this study,a starch-octanoic acid chemical conjugate(ST-OA)was synthesized via esterification between the hydroxyl group of a glucose monomer and the carboxyl group of octanoic acid.The critical micelle concentration of ST-OA was 282.66?g/mL.The particle size of ST-OA micelle was about 13.3nm,and transmission electron microscope(TEM)image exhibited its spherical shape.Then,the magnetic nanomicelle contained magnetic iron oxide nanoparticles was prepared,and the hydrophobic anticancer drug doxorubicin was further loaded by dialysis method.the physicochemical characteristics of prepared nanomicelle with different drug dosage were investigated.The size of magnetic nanomicelles was about 105nm.When doxorubicin was added,the particle size of drug-loaded magnetic nanomicelles increased by tens to 100nm,TEM image showed its spherical shape,and the particle sizes were relatively uniform.In certain conditions,along with an increase in dosage,drug encapsulation efficiency of nanomicelle gradually increased.Furthermore,magnetic response characteristics were observed through magnetically responsive experiment in vitro.In drug release studies,adriamycin released slowly from magnetic nanomicelle when PBS as release medium.Human hepatoma BEL7402 cell lines as a model,the cellular uptake results indicatedthe magnetic nanomicelle could successfully carry doxorubicin entry into hepatoma cells.MTT assay showed that cytotoxicity of ST-OA micelles was increased with dosage of drug loaded magnetic nanomicelle.The transmembrane transport experiments of drug-loaded magnetic nanomicelles showed that there was a significant increase in transmembrane transport with the use of magnetic field.Nude mice bearing ectopic BEL7402 liver tumors as model animals,drug loaded magnetic nanomicelle could achieve long-circulation in vivo,and enriched in the tumor site.The results in vivo antitumor efficacy showed the drug-loaded magnetic nanomicelles may have a certain anti-tumor effect.