Preparation For Nanoparticle Of Poorly Water-Soluble Drug By Dense Gas Technology

Presently, as the development of chemistry, biology, pharmaceutics and genetic technology, many new polymers and drugs has been synthesized and applied to the field of medicine and treatment. But most of the new drugs are poorly water-soluble drugs, so in medical practice, they hardly achieve the therapeutic efficacy which is expected because of poorly oral absorption. The bioavailability of the drugs is decreased greatly.Now, nanotechnology is employed to solve the problem of the dissolution rate of poorly water-soluble drugs due to its excellent characteristics. Dense gas technology which is an emerging technology has been received extensive attention nowadays. Because of its simple operation, lower residual solvent and environmentally favorable, dense gas technology has been used for preparation of the drug nanoparticle widely.A dense gas is a fluid close to or above the critical point, generally with a reduced temperature and pressure between0.9and1.2. In this paper, the GAS and ASES process have been used to micronize three poorly water-soluble drugs which are silybin, ginsenoside Re and ginsenoside Rh2. First, the research was focus on the preparation technology of nanoparticles of silybin. The result showed that GAS process could reduce the particle size range effectively, but not receive the particles with uniform morphology and size distribution forms. Some globular particles with uniform morphology could be prepared by ASES process. With the joining of dispersant (PVP), the fine particles with uniform morphology, narrow size distribution were obtained and the particle size ranged from100-200nm. The result of FT-IR and XRD showed that chemical construction of the drug had not changed but crystal form turned into amorphous state. The dissolution rate test indicated that the nanoparticles exhibited a higher dissolution rate obviously and there was a maximum8times greater than the raw drug in equal time.The preparation process of nanoparticle of ginsenoside Re used the fine procedure parameters which used in the preparation process of silybin. The result showed that temperature and pressure became the main factors of particle morphology and the particle size ranged from200-300nm. FT-IR and XRD analysis showed that the chemical structure still had no change and crystal form turned into amorphous state. The dissolution could reach99.17%within120min.The preparation process of nanoparticle of ginsenoside Rh2used the fine procedure parameters which used in the preparation processes of silybin and ginsenoside Re. The result showed that the nanoparticles with the particle size ranged from80-120nm could be prepared using ASES process. The increase of proportion of the poloxamer, as well as the rise of temperature and pressure, are beneficial to form the nanoparticles with more uniform particle size distribution. FT-IR and XRD analysis showed that the chemical structure of the particles had no change and crystal form turned into amorphous state. The dissolution could reach99.22%within120min.