Study On The Construction Of Targeted Drug Carrier And Its Antitumor Effect

ObjectivesSolid nanoparticles (SLN) have been developed rapidly in recent years. It has properties ofgood physiological compatibility, control the drug release and targeting efficiency. In thisstudy, biological endogenous stearic acid as a carrier and doxorubicin as a drug werechosen to prepare SLN. SLN were prepared by the modern nano-preparation technology,the prescription and process of SLN were optimized by the orthogonal design. Thephysical and chemical characteristics of SLN were studied by various methods. For SLNbecoming active target, SLN were connected with monoclonal antibodies to produceImmunonanoparticles (INP). The target and anti-tumor effect of INP were evaluated invitro.MethodsFirst the method to assay the concentration of doxorubicin (DOX) was established byHPLC. Doxorubicin nanoparticles (DNP) were prepared by a double emulsion method.Orthogonal design was used to optimize the prescription of preparing DNP on base ofentrapment rate (ER). Its appearance and size were studied by sanning electronmicroscope (SEM), its distribution and Zeta potential were observed by laser particle sizeanalyzer, and its drug release in vitro by dialysis were observed. INP formed of thecoupling of nanoparticles and trastuzumab (Herceptin) were determined for theiractivities and killing tumour cells effects by ELISA and MTT.Results1. The method of measuring the concentration of DOX by HPLC accorded withmethodology requirements, with good linear relationship, high accuracy and precision.2. The optimal prescription of preparing DNP:0.1ml DOX solution (10mg/ml) dropedinto1ml chloroform containing50mg stearic acid20mg phosphatidylcholine, andultrasounded1minute to form W/O first emulsion; then droped the first emulsion into theaqueous solution containing F-68and DSPE-PEG-COOH-2000, and ultrasounded1minute to form W/O/W double emulsion, then droped double emulsion to water phase (0~2℃), and then Mixing and volatiling naturally. 3. The nanoparticles were spherical or para-spherical with a mean size of (198.2±12.4) nm.Encapsulation ratio of68.6%and the release of50%drug in96hours in vitro weredetected, in vitro release behavior of DOX from nanoparticles could be described byHixon-Crowell model.4. ELISA indicated that INP kept the immunity active to SKBR3and SKOV3tumor cellswith high expressing HER2and had no activity to MCF-7with no expression of HER2.MTT suggested INP had significant higher killing SKBR3cells activity than DNP andDOX separately.Conclusions1.DNP reached the requirement of nano-drug and had slow-release effect.2.Immunity and target abilities of INP could effectively inhibit the growth of tumor cellswith high expression of HER2.