ABSTRACT
Objective To prepare vinorelbine bitartrate long-circulation liposomes by pH gradient loading methods and make characterization. Methods The impact of hydration temperature and extrusion times on the blank liposome particle size was investigated;and the incubation temperature and in duration on size and encapsulation percentage of drug loading liposome particle was tested. The vinorelbine bitartrate long-circulation liposome was characterized for particle size,polydispersion index, Zeta potential,morphology,and was studied for long term stability. Results The particle size,Zeta potential,polydispersion in-dex of long-circulation liposomes were (96. 4±27. 2) nm,(0. 162±0. 042),(-26. 7±3. 5) mV,respectively. The liposomes were small,unilamellar and spherical with smooth surface under transmission electron microscopy. Long term stability studies showed that the liposomes were stable for up to 3 months after storage at 5 ℃ . Conclusion The preparation technology for the vinorel-bine bitartrate long-circulation liposome by pH gradient loading methods is feasible.
ABSTRACT
OBJECTIVE: To investigate the tissue distribution and pharmacodynamics of vinorelbine bitartrate thermosensitive liposomes. METHODS: Subcutaneous xenotransplanted tumor model of human ovarian carcinoma SK-OV-3 in nude mice was established. The tumor inhibitory efficacy and biodistribution of drug were evaluated in nude mice by intravenous ad-minstration with vinorelbine bitartrate thermosensitive liposomes and vinorelbine bitartrate injection. RESULTS: The inhibition rate of vinorelbine bitartrate thermosensitive liposomes was remarkably higher than that of injection at same dose. Moreover, The drug concentration in heated tumor of mice administrated with vinorelbine bitartrate thermosensitive liposomes was a-bout 4 fold compared with that of mice administrated with injection. CONCLUSION: Vinorelbine bitartrate thermosensitive liposomes combined with hyperthermia could significantly increase drug concentration in local tumor tissue and promote tumor inhibitory efficacy.