| As the most advancing technology of traditional Chinese drug modernazition, nano traditional Chinese drug will become one of the most parts of traditional Chinese drug modernazition, which not only elevate the modernization and standardization of traditional Chinese drug and accelerate the step into international market, but also have revolutionary influence on the development of it. In this article, garlic oil(GO) was selected as model drug, which exhibit a variety of biological activities including hypolipidemic, antithrombotic, antiatherosclerotic, antimutagenic, anticarcinogenic and antibacterial effects, and solid lipid nanoparticle(SLN) was prepared by high pressure homogenization(HPH) and melt-ultrasound technology. On account of the good compatibility of GO and lipid, the problem of poor solubility of GO and the low drug loading capacity may be solved simultaneously. Firstly, diallyl trisulfide(DATS) and diallyl disulfide(DADS) were separated from GO as the standards of quality control; GO-SLN was prepared by HPH and melt-ultrasound technology and the freeze drying preparation of GO-SLN was prepared by lyophillization to enhance the storage stability. The finger print was made as the method of quality control. Finally, the pharmacokinetics and tissue distribution in rats was studied to reveal the fate in vivo of GO-SLN.DATS and DADS were separated and purified by preparation HPLC. The both contents were evaluated to be >95% by the methods of HPLC, GC-FID and GC-ECD. The results of degradation dynamics showed that both degraded to some extent in different pH solution, while pH was higher than 13, the degradation rate accelerated markedly. Both degraded more quickly in 20% plasma and 10% tissue homogenates than in water solution. The main degradation product of DATS was DADS identified by GC-MS.GO-SLN was prepared by HPH and melt-ultrasound technology, which glyceryl monostearate was lipid material and lecithin and poloxamer 188 as emulsifier. The particle size of GO-SLN by two methods was small and encapsulation efficiency was higher 90%. The single factor experiments were investigated the effects of technology factors (adding order, homogenization pressure and cycles, ultrasound power and time, et al) and formulation factors(the kinds and content of lipid phase, the kind and ratio of emulsifier and the content of GO) on particle size and distribution of GO-SLN. The orthogonal design was carried to optimize the formulation further. The particle size of the best formulation was 106.5±40.3nm and the encapsulation efficiency was 98.6％±1.8％.GO-SLN was prepared into freeze drying preparation with good appearance and reconstitution by lyophillization after the process and formulation parameters were optimized. The lose of GO was lower 10％and the stability of GO-SLN was highly improved. The cryoprotectants are necessary to protect SLN during lyophillization. The reeonstitution of the freeze drying preparation of GO-SLN with single cryoprotectant was poor and the phenomena of shrinking, bubbling or spurt bottle will happen in the formulations with glucose, fructose and sorbitol as cryoprotectant. However, the mixture of cryoproteetants can notably improve the appearance and reconstitution. Trehalose and maltose can accelerate the reeonstitution rate. The best formulation with 10％trehalose and 10％sucrose can reconstitute in 10s with manual shaking and the particle size increase from 106.5nm to155.3nm, which can reach the requirement. The microform was observed by microphotograph. The study of retained moisture showed that the retained moisture was about 5.4％after sublimation drying and free water in GO-SLN was almost removed. 2.2％of the retained moisture can be removed further by the drying under reduced pressure at room temperature. The retained moisture can be removed wholly by being heated at 100℃. However, the shringkage and change color happened visibly. The results of stability study showed that the freeze drying preparation of GO-SLN are still instable to heat and light, but it is stable away from light at 4℃,The characters of GO-SLN include the shape, particle size and distribution, drug status in SLN, encapsulation efficiency and release in vitro. In this study, the shape of GO-SLN and DATS-SLN was observed by transmission electron microscope(TEM), which is spherelike. The particle size and distribution was determined by PCS. The particle size of GO-SLN prepared by melt-emulsified ultrasound was higher than that by HPH.ζpotential of GO-SLN was determined by electrophoretic method, which was negative.ζpotential of drug-free SLN and GO-SLN was --9.9±6.6mv and --31.9±16mv, respectively. potential of the freeze drying preparation of GO-SLN was --34.7±9.6mv, which didn't nearly change.The result of DSC indicated that GO dispersed into lipid uniformly and form solid solution. Encapsulation efficiency is one of important index. In this study, sephadex filtration method, ultraeentrifugalization, ultrafiltration and freeze- coalescence filtration was used to determined encapsulation effieiency(EE). The results showed that EE was alike by ultraeentrifugalization and freeze-coalescence filtration, while the result by sephadex filtration method was lower. GO was wholly entrapped by ultraflltration membrane, so ultrafiltration method is not suitable to determine the EE of GO-SLN. The release study in vitro showed that GO-SLN in vitro first slight burst release, then release slowly.The standard finger print of GO-SLN was erected by I-IPLC and GC, respectively. Good similarities were found in fingerprints in 10 batches of GO-SLN. The similarity coefficient was higher than 0.99, so it can act the quality control standard of Go-SLN for injection.A GC-ECD method was developed for the determination of DATS and DADS in the plasma and biological samples of rats. The intravenous pharmacokinetic behaviors of GO solution and GO-SLN were investigated. The results showed that compared with GO solution, MRT of GO-SLN(13.8min) was shorter than that of GO solution(19.5 min). However, Cmax, and AUC of GO-SLN was twice of that of GO solution. GO-SLN significantly enhanced the bioavailability. The results of tissue distribution showed that GO-SLN distributed more quickly into tissues after intravenous injection and maintained a higher concentration and longer time in tissues, which indicated that the target efficiency enhanced. |
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