The Preparation And Evaluation Of Strychnos Alkaloids Microcapsules And Compound Volatile Oil Microcapsules

In order to reduce the release rate of Strychnos alkaloids and improve the stability of volatile oils, emulsion-solvent diffusion method was applied to prepare Strychnos alkaloids microcapsules and volatile oil microcapsules. During the preparation, ethyl cellulose (EC) was selected as the coating material, and the Strychnos alkaloids and volatile oils from four Chinese traditional medicines(Olibanum, Myrrha, Chuanxiong Rhizoma and Cinnamomi Ramulus) were applied as the core in this experiment. Single-factor test and orthogonal experiment design were applied to optimize the preparation conditions by using drug loading (DL), encapsulation efficiency (EE) and appearance of the microcapsules as the evaluation indexes. HPLC methods for detecting the content of brucine, strychnine and cinnamaldehyde were established. The morphology, size distribution and the in vitro release of microcapsules were studied.The experimental results indicated that the optimal preparation conditions of Strychnos alkaloids microcapsules were listed as follows:the mass concentration of EC was0.135g/mL, and the mass ratio of strychnine alkaloids to EC was1:2. Concentration of emulsifier was2%, and volume ratio of the organic phase to the aqueous phase was1:5. The average EE and DL capacity of Strychnos alkaloids in the microcapsules were53.99%and18.25%, respectively. The optimal preparation conditions of volatile oil microcapsules were showed as follows as well:the mass concentration of EC was0.18g/mL, and the volume and mass ratio of volatile oils to EC was1:3. Concentration of emulsifier was1%, and volume ratio of the organic phase to the aqueous phase was1:5. The average EE and DL capacity of cinnamaldehyde in the microcapsules were42.94%and2.22%, respectively. The DL capacity of volatile oil was13.41%.The results of scanning electron microscope showed that the two kinds of microcapsules both had good sphericity and smooth surface. There were some small holes on the surface of the microcapsules which might promote the dissolution. Strychnos alkaloids microcapsules and volatile oil microcapsules had narrow particle size distribution The average particle sizes of them were523.711μm and805.726μm, respectively. The accumulative releasing rate of Strychnos alkaloids and cinnamaldehyde in artificial gastric juice was about99.89%and 75.14%of the total quantity in12hour, respectively. The above results showed that the release properties of Strychnos alkaloids and four kinds of volatile oils were improved by preparing them into Strychnos alkaloids microcapsules and volatile oil microcapsules respectively.