【摘 要】
：
Polypropylenimine (PPI) dendrimers have been widely used (i)s effective delivery vehicles for drugs and nucleic acids during the past decade.[1,2] However,biomedical applications of PPI dendrimers wer
【机 构】
：
Shanghai Key Laboratory of Regulatory Biology, School of Lifc Science, East China Normal University,
【出 处】
：
2012年全国高分子材料科学与工程研讨会
论文部分内容阅读
Polypropylenimine (PPI) dendrimers have been widely used (i)s effective delivery vehicles for drugs and nucleic acids during the past decade.[1,2] However,biomedical applications of PPI dendrimers were limited due to their serious cytotoxicity and low drug loading capacity.In the present study,aeetylated PPI dendrimers with different acetylation degrees ranged from 14.2% to 94.3% were synthesized and used to encapsulate drugs including methotrexate sodium,sodium deoxycholate,and doxorubicin.Acetylated PPI dendrimers with an aeetylation degree above 80% showed a significantly decreased cytotoxicity (> 90% cell viability) on MCF-7 and A549 cells.The drug loading capacity of acetylated PPI dendrimers increased proportionally with the acetylation degree on dendrimer surface.In addition,94.3% acetylated PPI dendrimers exhibited a pH-responsive release profile of anticancer drugs loaded within the nanoparticles (Figure 1).The cytotoxicities of methotrexate sodium and doxorubicin on MCF-7 and A549 cells are significantly reduced when they were complexed with acetylated PPI dendrimers with high acetylation degrees (>80%) due to sustained drug release from the dendrimers.The results suggest that surface acetylation is critical in the design of biocompatible and high efficient dendrimers,and that acetylated PPI dendrimers are promising vehicles for anticancer drugs in clinical trials.
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