Studies On Preparation Of AFGF Cationic Liposomes And Its Pharmacokinetics In Rats

As we know aFGF (acid fibroblast growth factor) plays an important role in organism for its numerous bioactivity.However, aFGF is unstable and sensitive to temperature, pH and metal ion, it still has a bottle neck on clinical application.Objective: In this study, we made cationic liposome as a drug carrier for aFGF in order to effectively protect aFGF from unstabilizing factors, established the quality assessment system of aFGF cationic liposome,and researched on its release kinetics in vitro and pharmacokinetic in vivo.Methods:AFGF cationic liposomes were prepared by pH-gradient, the formulation and preparation were optimized by single-factor test with encapsulation efficiency of liposomes as the parameter, and the reproducibility of the best preparation was studied.The physical and chemistry properties of aFGF cationic liposome was identified by Cryo transmission electron microscopy and laser light scattering, and its stability was also researched. The vitro release kinetics of aFGF cationic liposome was investigated by Dialysis method. Observed the influence of drug release between different release medium, and also researched the difference with aFGF solution. Studied pharmacokinetic of aFGF cationic liposomes after intravenous and intraperitoneal administration in rats, and discussed the difference with aFGF solution.Results:Optimization experiments to determine the optimal formulation and process conditions, stearylamine (0.02 g), citric acid buffer (0.03 mol/L), aFGF (0.04 mg/mL), ApH (3.5), incubation temperature (35℃), incubation time (15 min), the preparation of aFGF cationic liposome encapsulation efficiency was (78.82±2.56)%.The mean diameter of aFGF cationic liposomes was 124.03nm, Zeta potential was 9.68mV. Stability studies indicated that aFGF liposome should be stored at low temperature 4℃, it was unstable above 25℃.In vitro release kinetics study showed that, aFGF cationic liposome had some sustained release compared to aFGF solution, similar behavior in various release medium.Pharmacokinetic results had showned that aFGF cationic liposomes obvious prolonged the half-life in vivo, compared with aFGF solution. And there is a good correlation between the release characters in vivtro with the release in vitro.Conclusion:Research indiated, aFGF cationic liposomes had high encapsulating efficiency, physical chemical stability, and sustained release in vivo.