Preparation Of Novel Drug-loaded Microbubble And In Vivo Preliminary Experiment

PART I PREPARATION OF THE COMPLEX OFPACLITAXEL LOADED PLGA-COOH NANOPARTICLESAND LIPID MICROBUBBLESObjective Use adivin-biotin technique to prepare a kind ofPaclitaxel loaded novel microbubble,then test its physical and chemicalproperties.Methods The Paclitaxel loaded high molecular polymerPLGA-COOH nanoparticles(Pac-PLGA) were produced by the singleemulsion technique.Then dectect its encapsulation efficiency and thedrug-loading amounts.The connection between Streptoavidin andPac-PLGA which was used by carbodiimide technique detected byimmunofluorescence.MB-NH2and MB were prepared by mechanicalshaking. The study was divided into two groups which were adivin-biotingroup and contral group. The connection effect was observed under laserconfocal microscope at different time. Results The average diameter of Pac-PLGA was (131.1±29.7)nm.Ithad uniform size,good dispersion which were determined under theelectron microscopy. The encapsulation efficiency was (85±2.1)%.Thedrug-loading amounts was (4.25±0.16)%.Immunofluorescent showed thatSA was successfully linked to the surface of Pac-PLGA. In contral group(MB+Pac-PLGA), Pac-PLGA were not conjugated to the surface ofmicrobubbles. However, in adivin-biotin group(BIO-MB+SA-Pac-PLGA),it showed that a number of Pac-PLGA gathered around microbubbles like agarland under laser confocal microscope.Conclusions A novel drug loaded ultrasound microbubble areprepared successfully. It is potential to provide a new drug delivery andtargeted drug delivery system on tumor therapy. PART II POSITIONING RELEASE OF THE COMPLEXOF PACLITAXEL LOADED PLGA-COOHNANOPARTICLES AND LIPID MICROBUBBLES IN THELIVER OF MICEObjective To investigate the positioning release of drug and PLGAnanoparticles of the novel ultrasound microbubble with ultrasound in the liver of mice.Methods Use adivin-biotin technique to prepare Paclitaxel loadednovel microbubble. The mice were divided into3groups,i.e.Paclitaxelloaded PL GA nanoparticles group(Pac-PLGA group),Mixing Group,novelmicrobubble group.After injected into mice via the tail,the mice were allradiated by ultrasound on their surface.Mice were sacrificed after1h to taketheir liver tissue to measure the drug concentrations in each Mouse.Laserscanning confocal microscope was used to observe the distribution ofPLGA nanoparticles in liver of mice.Results The Paclitaxel content in novel microbubble group wa（s5.335土1.087）ug/g,which was higher than mixing group（4.067土0.954）ug/gand Pac-PLGA group（2.908土0.925）ug/g,p<0.01.And mixing group washigher than Pac-PLGA group （p<0.01）.Laser scanning confocalmicroscope was used to observe per high power filed(x400) the number offluorescently labeled Pac-PLGA nanoparticles.Pac-PLGA group had(17.590土5.811),mixing group had (31.227土7.177）,novel microbubblegroup had (47.500土7.301)，The amount of Pac-PLGA nanoparticles innovel ultrasound microbubble group was significantly higher than in theother groups(p<0.01),while in Mixing group was higher than in Pac-PLGAgroup(p<0.01).Conclusions The Paclitaxel content and the amount of PLGAnanoparticles in novel ultrasound microbubble group was significantly higher than in the other groups.The novel ultrasound microbubble canobviously improve the concentration of Paclitaxel and PLGA nanoparticlesin the target tissue. so that it can improve the treatment of diseases.