摘要
We report on the fabrication of self-assembled micelles from ABC-type miktoarm star polypeptide hybrid copolymers consisting of poly（ethylene oxide）, poly（L-lysine）, and poly（e-caprolactone） arms, PEO（-b-PLL）-b-PCL, and their functional applications as co-delivery nanocarriers of chemotherapeutic drugs and plasmid DNA. Miktoarm star copolymer precursors, PEO（-b-PZLL）-b-PCL, were synthesized at first via the combination of consecutive ＂click＂ reactions and ring-opening polymerizations （ROP）, where PZLL is poly（e-benzyloxycarbonyl-L-lysine）. Subsequently, the deprotection of PZLL arm afforded amphiphilic miktoarm star copolymers, PEO（-b-PLL）-b-PCL. In aqueous media at pH 7.4, PEO（-b-PLL）-b-PCL self-assembles into micelles consisting of PCL cores and hydrophilic PEO/PLL hybrid coronas. The hydrophobic micellar cores can effectively encapsulate model hydrophobic anticancer drug, paclitaxel; whereas positively charged PLL arms within mixed micellar corona are capable of forming electrostatic polyplexes with negatively charged plasmid DNA （pDNA） at N/P ratios higher than ca. 2. Thus, PEO（-b-PLL）-b-PCL micelles can act as co-delivery nanovehicles for both chemotherapeutic drugs and genes. Furthermore, polyplexes of pDNA with paclitaxel-loaded PEO（-b- PLL）-b-PCL micelles exhibited improved transfection efficiency compared to that of pDNA/blank micelles. We expect that the reported strategy of varying chain topologies for the fabrication of co-delivery polymeric nanocarriers can be further applied to integrate with other advantageous functions such as targeting, imaging, and diagnostics.
We report on the fabrication of self-assembled micelles from ABC-type miktoarm star polypeptide hybrid copolymers consisting of poly（ethylene oxide）, poly（L-lysine）, and poly（e-caprolactone） arms, PEO（-b-PLL）-b-PCL, and their functional applications as co-delivery nanocarriers of chemotherapeutic drugs and plasmid DNA. Miktoarm star copolymer precursors, PEO（-b-PZLL）-b-PCL, were synthesized at first via the combination of consecutive ＂click＂ reactions and ring-opening polymerizations （ROP）, where PZLL is poly（e-benzyloxycarbonyl-L-lysine）. Subsequently, the deprotection of PZLL arm afforded amphiphilic miktoarm star copolymers, PEO（-b-PLL）-b-PCL. In aqueous media at pH 7.4, PEO（-b-PLL）-b-PCL self-assembles into micelles consisting of PCL cores and hydrophilic PEO/PLL hybrid coronas. The hydrophobic micellar cores can effectively encapsulate model hydrophobic anticancer drug, paclitaxel; whereas positively charged PLL arms within mixed micellar corona are capable of forming electrostatic polyplexes with negatively charged plasmid DNA （pDNA） at N/P ratios higher than ca. 2. Thus, PEO（-b-PLL）-b-PCL micelles can act as co-delivery nanovehicles for both chemotherapeutic drugs and genes. Furthermore, polyplexes of pDNA with paclitaxel-loaded PEO（-b- PLL）-b-PCL micelles exhibited improved transfection efficiency compared to that of pDNA/blank micelles. We expect that the reported strategy of varying chain topologies for the fabrication of co-delivery polymeric nanocarriers can be further applied to integrate with other advantageous functions such as targeting, imaging, and diagnostics.
基金
supported by the National Natural Science Foundation of China (Nos. 21274137, 91027026 and 51033005)
Fundamental Research Funds for the Central Universities
Specialized Research Fund for the Doctoral Program of Higher Education (SRFDP, 20123402130010)
