| Summary: | 碩士 === 高雄醫學大學 === 藥學研究所 === 97 === A lot of studies have proven that decay rate and many diseases obviously correlate with free radicals attack to living cells and its generated metabolic product. Hence antioxidants can against free radicals and avoid oxidative damages for human, and then decrease generation of chronic diseases. In recent years, numerous studies indicated that catechin not only remove free radicals but has various types of pharmacological properties such as anti-inflammatory, anti-viral, anti-bacterial, anti-mutagenic and anti-carcinogenic. However the oral bioavailability of catechin is known to be low (2~5%), and the systemic clearance is also high. The purpose of this experiment was to promote oral bioavailability of catechin with liposomal formulation and prolong duration time of drug in plasma.
We used phospholipid, Epikuron 200, and cholesterol as material to prepare liposome formulation, and discuss the effect of liposome formulation which contain phospholipid and cholesterol or the mix of ionic surfactants such as stearylamine, dicetyl phosphate and nonionic surfactant such as Tween 80. For the three group that physical properties of drug entrapment efficiency, particle size and stability of formulation on day 0, 14, 21 and 30 were respectively compared, and further, we were sieve out optimization of formulation. Preparation of three group of liposome that the mean diameters were 35~65 nm and the entrapment efficiency were 50~80%. According to in vitro release experiment result, the optimization of formulation, catechin accumulated amount was 55% at 12 hour.
After sieve out optimization of formulation, we using oral administration for health rats with dosage 30 mg/kg of catechin. Compared with catechin solution, we observed the pharmacokinetics and distribution in brain tissue. In vivo result, we found the area under the curve and bioavailability of catechin-liposome were better than solution.
|
|---|
