(聚酰胺-胺)树状大分子对甲氨蝶呤的复合和释放研究

以甲氨蝶呤(MTX)为模型药物,研究了PAMAM与MTX的复合及体外释放.1H-,13C-NMR数据表明MTX与PAMAM树状大分子形成复合物是由于MTX羧基和PAMAM树状大分子外端氨基之间的相互作用.该复合物在pH=7.4,10 mmol/L Tris-HCl中非常稳定,表现出明显的缓释效果.当溶液中的离子强度增加时,会破坏PAMAM-MTX复合物的稳定性,缓释作用部分或全部失去,说明PAMAM树状大分子与MTX之间的相互作用属于静电作用.UV测得每个G5.0 PAMAM、G4.0 PAMAM树状大分子分别能复合271、4个MTX分子.

INVESTIGATION OF PAMAM DENDRIMER-MTX COMPLEX: FORMATION AND in vitro RELEASE

The mechanism of formation of polyamidoamine(PAMAM) dendrimer-methotrexate(MTX) complex and the release behaviors of MTX from the complex have been investigated.()~1H-,()~(13)C-NMR data confirmed that the formation of PAMAM-MTX complex was due to the interaction between PAMAM external amino groups and the MTX carboxyl groups.The PAMAM-MTX complex was stable in 10 mmol/L,pH 7.4 tris-HCl buffer solution.However,with increasing the ionic strength in the buffer solution,it was easier for MTX to escape from the complex,which suggested that the interaction between PAMAM and MTX was electrostatic in nature.UV results demonstrated that the higher the generation of PAMAM,the greater its capacity to carry MTX molecules,(e.g.)G.5.0 PAMAM and G4.0 PAMAM could load 27 and 14 MTX molecules,respectively.