Block copolymer-coated calcium phosphate nanoparticles sensing intracellular environment for oligodeoxynucleotide and siRNA delivery
Block copolymer-coated calcium phosphate nanoparticles sensing intracellular environment for oligodeoxynucleotide and siRNA delivery
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DOI：
10.1016/j.jconrel.2004.03.031
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发表时间：
2004-06-18
影响因子：
10.8
通讯作者：
Kataoka, K
中科院分区：
文献类型：
--
作者：
Kakizawa, Y;Furukawa, S;Kataoka, K
利用聚乙二醇-聚天冬氨酸嵌段共聚物（PEG-PAA）与磷酸钙的自缔合现象，制备了包埋寡脱氧核苷酸（ODN）或siRNA的有机-无机杂化纳米颗粒。根据PEG- paa浓度的不同，纳米颗粒的直径在几百纳米范围内，并且由于围绕磷酸钙核心的PEG层的位阻排斥效应而显示出优异的胶体稳定性。ODN和siRNA的负载能力相当高，在最佳条件下几乎达到100%。流式细胞分析和共聚焦显微镜观察表明，负载ODN的杂化纳米颗粒通过内吞机制被细胞吸收。此外，磷酸钙核心在细胞内环境中解离，与外部环境相比，钙离子浓度明显降低，允许以受控的方式释放掺入的ODN和siRNA。最终，通过激光共聚焦显微镜观察fitc标记的ODN，证实了这些核酸基药物在细胞内的有效递送和核定位。混合纳米颗粒的这种智能离子敏感特性进一步被掺入纳米颗粒的siRNA对报告基因表达的明显沉默所证实。(C) 2004 Elsevier B.V.版权所有
The organic-inorganic hybrid nanoparticles entrapping oligodeoxynucleotide (ODN) or siRNA were prepared through the self-associating phenomenon of the block copolymer, poly(ethylene glycol)-block-poly(aspartic acid) (PEG-PAA), with calcium phosphate. The nanoparticles have diameters in the range of several hundreds of nanometers depending on the PEG-PAA concentration and revealed excellent colloidal stability due to the steric repulsion effect of the PEG layer surrounding the calcium phosphate core. The loading capacities of ODN and siRNA were fairly high, reaching almost 100% under optimal conditions. The flowcytometric analysis and confocal microscopy observation indicated that the hybrid nanoparticles loaded with ODN were taken up by the cells through the endocytosis mechanism. Furthermore, the calcium phosphate core dissociates in the intracellular environment with appreciably lowered calcium ion concentration compared to the exterior, allowing the release of the incorporated ODN and siRNA in a controlled manner. Eventually, effective intracellular delivery and nuclear localization of these nucleic acid-based drugs were evidenced through the observation of laser confocal microscopy using FITC-labeled ODN. This smart ion-sensitive characteristic of hybrid nanoparticles was further demonstrated by the appreciable silencing of reporter gene expression by siRNA incorporated in the nanoparticles. (C) 2004 Elsevier B.V. All rights reserved.