Experimental Investigation Of The Ultrasound Imaging And Penetration Of LHRH-nanobubbles In Vivo

PART IObjective: To prepare non-targeting liposomal microbubble and luteinisinghormone releasing hormone(LHRH) nanoliposomal microbubbles specifically targeting ovarian cancer cells through biotin-avidin mediation and lyophilization/ sonication method.Methods: DPPC,DSPE/DSPE-PEG(2000)Biotin, glycerin and phosphatebuffere- dsaline(PBS) were mixed in certain proportion, lyophilization/sonication method and mechanical oscillations were used to prepare non-targeting nanoliposomal microbubbles(N-NBs)/biotinylated non-targeting nanoliposomal microbubbles(Bio-N-NBs). Using the biotin-avidin bridge method, conjugated biotinylated LHRH antibodies to Bio-N-NBs generated biotinylated LHRH nanoliposomal microbubbles(LHRH-NBs) targeting specifically ovarian cancer cells.Results: The rounded and uniformly distributed N-NBs and LHRH-NBs were successfully generated. The particle size with a mean of 360 nm for N-NBs or with a mean of 500 nm for LHRH-NBs.They can be kept 7days at room temperature.Conclusion: N-NBs and LHRH-NBs were successfully generated through biotin-avidin mediation and lyophilization/sonication method.PART â…¡Objective:To investigate the ultrasound imaging abilities of N-NBs and LHRH-NBs in models of transplanted tumor.Methods:Transplanted tumor on nude mice were randomly divided into 3 groups, observe the abilities of different contrast agents(N-NBs,LHRH-NBs, Sono Vue)ultrasound imaging after the xenografts were injected with contrast agents via the tail vein.Results:There were not statistically difference between the three groups(P>0.05);compared with Sono Vue, the time of ultrasound imaging of N-NBs and LHRH-NBs is longer(P<0.001).Conclusion: There were not statistically difference between the three groups in ultrasound imaging ability,but the time of ultrasound imaging of nanobubbles is longer than Sono Vue.PART â…¢Objective: To investigate the penetration of NBs and LHRH-NBs and the binding of LHRH-NBs to human OVCAR-3 ovarian cancer cells.Methods: Di I-labeled NBs and LHRH-NBs were injected into the tail vein of different nude mice, we used fluorescence microscope to confirm that the NBs and LHRH-NBs were small enough to pass through the endothelial gaps of tumors.The binding of LHRH-NBs and N-NBs to human OVCAR-3 tumor cells were detected by immumofluorescence.Results: Both N-NBs and LHRH-NBs can pass through the endothelial gaps of tumors,a number of LHRH-NBs can bind to tumor cells.Conclusion: Nanobubbles can penetrate the endothelial gaps of tumors and LHRH-NBs can bind to tumor cells.