pH响应PAMAM基星型大分子的合成、表征及控释性质

pH-sensitive star polymer based on PAMAM dendrimer, PAMAM-A-PEG, was designed and synthesized via surface modification of hydrophobic unit and PEG molecules, and characterized using IR, NMR and GPC/MALLS. Its properties in solution were studied using DLS and zeta potential. It was proved that PAMAM-A-PEG had relative stability and could hydrolyze rapidly in acidic solution. Rose Bengal (RB) was used as a model guest molecule to study the encapsulating and releasing properties of the polymers. The results indicated that the star polymer could increase the resolvability of RB in some solution attributed to electrostatic interaction between host-guest molecules and the polymer, and the release behavior of RB can be regulated by adjusting the pH and ions strength in solution. In addition, the hydrophobic group on the surface of PAMAM can act as barriers to keep RB inside, and thus exhibited good retarded releasing properties.