[Pharmacokinetics and distribution of superoxide dismutase liposomes in rats].

Aim: To evaluate the effects of surfactants on the pharmacokinetics and distribution in rats after intravenous administration of SOD liposomes.

Methods: The liposomes were prepared by reverse phase evaporation method. The activity of SOD was assayed by method of xanthine oxidase.

[Study on nerve growth factor liposomes on crossing blood-brain barrier in vitro and in vivo].

Aim: To study the permeability of nerve growth factor (NGF) liposomes (NGF-L, NGF-SSL, NGF-SSL-T) on the blood-brain barrier (BBB) model and the distribution in vivo, and analyze the correlation between the results in vitro and in vivo.

Methods: The BBB model in vitro was established by using mouse brain microvascullar endothelial cell, and the model was applied to study the permeability of NGF liposomes. The distribution of NGF of each group was studied by 125I labeled and SDS-PAGE method.

[Therapeutic efficiency of amphotericin B liposome modified by RMP-7 to transport drug across blood brain barrier].

Aim: To study the therapeutic efficiency of amphotericin B liposome (AmB-L) targeting to the brain in mice with meningitis.

Methods: Amphotericin B liposome targeting to the brain were prepared by film-sonication method. Their concentration and encapsulation percentage were determined.

[Establishment of an in vitro model of brain-blood barrier].

Objective: To establish an in vitro model of brain-blood barrier (BBB) using cultured mouse brain microvascular endothelial cells (BMVEC).

Methods: Mouse BMVEC were seeded on micro-pore membrane of gelatin-coated cell culture insert and cultured to confluence. The establishment of BBB was preliminary judged by a 4 h water-leaking test.

[Effect of RMP-7 and its derivatives on the transportation of liposome into the brain].

Aim: To study the action of RMP-7 and its derivative on transporting liposome across the blood brain barrier (BBB) into the brain.

Methods: RMP-7 and DSPE-PEG-NHS [[1,2-dioleoyl-sn-glycero-3-phosphoethanolamine-n-[poly (ethylene-glycol)]-hydroxy succinamide]] were conjugated together in mild condition and MALDI-TOF-MS (Matrix-Assisted Laser Desorption-Ionization Time-of-Flight Mass Spectrometry) was used to determine their molecular ratio. An in vitro BBB model was established and used to determine in vitro bioactivity of RMP-7 and its derivative.

[Effect of surfactants on the in vitro and in vivo properties of amphotericin B liposome].

Aim: Some surfactants such as DSPE-PEG, Tween 80 and Brij 35 were used to modify the amphotericin B liposome, improve the stability, optimize the tissue distribution and decrease the toxicity of amphotericin B liposome.

Methods: The amphotericin B liposome was prepared by the film-supersound method. The effects of cholesterol and amphotericin B on the encapsulation percentage were studied.

[Studies on the formation mechanism of alginate-chitosan microcapsule and its drug-loading and release properties on macromolecular drug].

Aim: To investigate the formation mechanism, macromolecular drug loading capacity and release property of alginate-chitosan microcapsules (ACM).

Methods: ACM was prepared by emulsification-gelation method and its formation mechanism was studied by DSC analysis. Using bovine serum albumin (BSA) as model drug, the drug loading and release properties of the microcapsules on macromolecular drug were investigated.

[Preparation of thrombus-targeted urokinase liposomes and its thrombolytic effect in model rats].

Aim: To prepare thrombus-targeted urokinase liposomes and observe its improved thrombolytic efficacy on thrombus model rats.

Methods: The ligand H-Arg-Gly-Asp-Ser-OH (RGDS) which has specific affinity to thrombus was synthesized by liquid phase method and anchored on the surface of liposomes by incorporating its conjugate with DSPE-PEG3,500-COOH into liposomal lipid bilayers, thus thrombus-targeted liposomes were produced. Urokinase (UK) liposomes were prepared at room temperature through method modification using hydrogenated soy phosphatidylcholine (HSPC); the in vivo thrombolysis of the obtained thrombus-targeted UK liposomes and its comparison with TBS (Tris-HCl buffered solution) control, free UK and UK liposomes were assessed on common carotid artery model rats.

[Study on the hepatocytic cell targetability of liposomes].

Aim: To target for hepatocytic cell, liposomes was modified by special ligand.

Methods: Sterically stabilized liposomes (SSL) was conjugated with asialofeticin (AF), the ligand of asialoglycoprotein receptor (ASGP-R) of hepatocyte. ASGP-R-BLM is the ASGP-R reconstructed on bilayer lipid membrane (BLM).

Studies on alginate-chitosan microcapsules and renal arterial embolization in rabbits.

Spherical and well-dispersed alginate-chitosan microcapsules, with a mean diameter of 77.28+/-0.93 microm (n=3), were prepared by the emulsification-gelation method.