초록 |
One of the strongest naturally occurring antioxidants is alpha-lipoic acid (ALA) which exists as lipoamide in at least five proteins. Many experimental and clinical studies have proved beneficial effects of ALA in such diseases as diabetes, heart diseases, AIDS, and anti-obesity. It had been reported that polymerization readily occurred by SN2 reaction as a result of thiolate-disulfide interchange, and from heat above its melting point (63oC). However, until recently, there are seldom studies about bioavailability and characteristics of polymers of ALA (disulfide polymer). Therefore, our studies focus on conditions of polymerization of ALA and characteristics of these polymers. ALA was polymerized in water bath of 70oC which is the temperature enough to generate free radicals by ring opening of cyclic five-membered disulfide. To verify the application and biocompatibility for drug delivery, drug release and drug loading tests were executed in various pH solutions at 36.5oC. |