Studies On Mat-Freeze-Dried Liposome

Matrine is a alkaloid which is abdundant in Sophora Flavescens Ait, S. AlopecuroidesL、S. Subprostrata Chun et T. Chen, which has inhibition on the experimental tumor. It isreported that Matrine can lighten the symptoms, lengthen survival period, does not destroythe production of the normal leucocyte, can even raise the number of leucocyte, improveorganism resistance used in treating various kinds of later cancer, this is difficult to manychemotherapy medicines. Liposomes is used as a cartier of anticancer drugs extensively inrecent years, it can improve chemotherapy target tropism of medicine to a certainextent, reduce chemotherapy medicines malicious effect of medicine by a largemargin, raise chemotherapy treatment index of medicine from several ways. Comparedwith other forms of an anticancer drug at present, liposomes has unique advantages, it canimprove stability, target tropism and long result of medicine and reduce dosage, etc. Weselected liposomes to entrap matrine for formulating high-efficient natural medicine againstcancer.In this paper, ammonium sulfate gradients method was developed to prepare thematrine liposome. To improve the instability of liposome, freeze-drying technique wasutilized to prepare freeze-dried liposome. The content of matrine extraction and theentrapment efficiency were accurately determined. Liposome physicochemicalproperties, stabilities were also investigated in this paper. The tissue distribution of thematrine liposomes were observed in mice in order to investigate the target tropism.Firstly, we studied the membrane material purchased in the market by oxidizing indexmethod, the result showed that the phospholipids fulfiled the requirement. The liposomeswere prepared by the following methods:Ether injection、TFV、REV(reverse-phaseevaporation vesicle method)、FTV、pH gradient vesicle method、ammonium sulfategradients method, etc. A method was developed to determine the content of matrine bymethanol extraction and UV spectrophoto-metry. Dialytic method、Sephadex G-50chromatography and minicolumn centrifuge method were used to separatenon-encapsulated drugs from liposomes. The results indicated that the minicolumncentrifuge—UV method was simple and accurate and easy to operate. The encapsulation ofliposomes prepared by ammonium sulfate gradients method was the highest. Based with pretrival, we choosed the single factors firstly and then optimized methodby orthogonal design and came out the best technology. Weighed by entrapment efficiencyof matrine in liposome, we prepared the matrine liposome. To resolve the instabilityproblem of liposome dispersion, freeze-drying technique was utilized to preparefreeze-drying liposome. Its main advantage is of high stability because of its solid formduring preservation. It can be readily and quickly reconstituted by adding water and simplestirring before use to form liposome dispersion with the same characteristics as beforefreeze-drying.We examined the dissolution profiles in vivo using dynamoic dialyzetion, checked theconcentration of drug by HPLC, observed the appearance by TEM with negative stainingand measured the particle diameter, measured the targeting capability by observing the drugconcentration in mice. The results showed that using the defined method, we prepared goodMATRINE-Freeze-Drying liposome:it has cream colored, full and loose appearance; gooddissolubility; round and oval granule appearance through TEM, well-distributed particlesize distribution, as 96%～99% is during 60nm～300nm, and the equally diameter is155nm; In vivo experiment showed that the relation of culminateve drug and time accord toWeibull equation; Using HPLC, we found both the peak figure of drug and the standardcurve were ideal, and the average concentration is 40.71mg, the average entrapmentefficiency is 82. 38%, drug loading ratio is 5.48%; we also setup the preliminary qualitystandard of MATRINE-Freeze-Drying liposome. The initial stability test displayed that theproduct is stable. In the vein injection experiment on animal, we can see that they havegood distinct targeting capacity.The experiments make clear that the preparation technology was feasible andrepeatable. All targets tests indicate the MATRINE-Freeze-Drying Liposome conform toChinese pharmacoeia criterion(Edition 2005). The experiment proves they have a goodtargeting capability. For basic, we have attain what we want as we expected. This text hadoffered certain theoretical research for the study of matrine liposomes.