Study On Preparation And Properties Of Nanoparticles Loaded With Ginkgolide A

Ginkgolide was recognized as platelet-activating factor antagonist which was the main efficacy component from Ginkgo biloba extract and its preparations. Ginkgo biloba terpene lactones A and B had neuroprotective effect by inhibiting the protein kinas C, so it could treat neuropathy, in particular, demyelization neuropathy, spinal cord disease, and cerebral edema. In addition, the cardiovascular system diseases, acute cerebral infarction, simple diabetic retinopathy could be treated by ginkgolide as the role of effective regulator on arteries, veins and capillaries. However, because ginkgolide was poorly water-soluble, short biological half-life, its applications in the medicine were seriously restricted. For the purpose of improving the pharmacological properties of ginkgolide, nano-liposome was used as drug carriers.Ginkgolide A was entrapped in the drug carriers with nanometer size nano-liposomes and chitosan nanoparticles. These materials possessed easily biodegrad and good biocompatibility and the advantages of primarily consisting of protection of biological activity of drugs, improving stability, extending the half-life, controlling drug release, improving efficacy, et al. Not only the nanotechnology, but also the targeted drug delivery technology were operated in this reported to prepared the nano-liposomes and chitosan nanoparticles loaded with ginkgolide A.In this report, a simple method would be reported for preparing size-controlled using the dextran gels, which had been added in the preparation of nano-liposomes loaded with ginkgolide A. In vivo, the particle size of nano-liposomes was one of the most important consideration factors. It was shown that the particle size was smaller, the radius of curvatuer in its circulation should be shorter and the effect of protein absorption should be less. Therefore, half-time of drug could be extended by reducing the particle size, and nano-liposomes had the ability to evade the interception by sinusoidal vessel of liver and spleen. The current methods of controlling or reducing the particle size during preparation were usually by changing the power of ultrasound, stirring speed, temperature, lipid ratio, et al. As the result, the optimized effect was not obvious with heavy workloads. In the process of making nano-liposomes loaded with ginkgolide A, dextran gels were added in the aqueous phase. The results showed that the particle size of nano-liposomes could be controlled by constraint spaces of dextran gel during the preparation. Morphology and stability of nano-liposomes were demonstrated better after using dextran gels and when the apertures of dextran gels were narrower, the nano-liposomes were also getting smaller. Furthermore, these nano-liposomes possesed the features of small size, spherical smooth surface, good stability, delayed release, high entrapment efficiency and drugloading, so they were consistent with the applications of nano-liposomes loaded with drugs excellently.Sialic acid was combined with chitosan and then this nanoparticle with targeting was prepared by the method of ionic crosslinking. The physical and chemical properties of the SA-CS-nanoparticles loaded with ginkgolide A were detected. As a result, the nanoparticles appeared spherical shape, the particle size was about 416.12±15.20 nm and the zeta potential was-18.32±3.89 mV, entrapment efficiency and drugloading were 88.10±8.15%and 32.37±2.64%, respectively. Furthermore, it has a good stability at low temperature, and the drug release in vitro was showed to be controlled.As a result, the preparation of nanoparticles was improved, and novel methods were offered to make the manufacturing process simple and workable. It provides theoretical foundation, and has a strong practical significance for product development from this study on nano-liposomes and nanoparticles loaded with ginkgolide A. Drug disposition of in vivo study indicated that the control release in serum was obviously. The targeting to brain and liver were increased obviously by the means of nano-liposomes and chitosan nanoparticle loaded with ginkgolide A, respectively.