Synthesis, stability, and cellular internalization of gold nanoparticles containing mixed peptide-poly(ethylene glycol) monolayers
Synthesis, stability, and cellular internalization of gold nanoparticles containing mixed peptide-poly(ethylene glycol) monolayers
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DOI：
10.1021/ac061578f
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发表时间：
2007-03-15
影响因子：
7.4
通讯作者：
Feldheim, Daniel L.
中科院分区：
文献类型：
--
作者：
Liu, Yanli;Shipton, Mathew K.;Feldheim, Daniel L.
金纳米粒子作为治疗剂、治疗递送载体和细胞内成像剂显示出巨大的前景。对于许多生物医学应用来说，选择性细胞和核靶向是可取的，并且这些仍然是体内使用纳米颗粒的重大实际挑战。通过将细胞靶向肽或抗体掺入纳米颗粒表面来解决这一挑战，这些修饰经常损害纳米颗粒在高离子强度生物介质中的稳定性。我们在此描述了聚（乙二醇）（PEG）和混合肽/PEG单层在金纳米颗粒表面上的组装。所得生物缀合物在高离子强度介质中的稳定性被表征为纳米颗粒尺寸、PEG长度和单层组成的函数。总共探索了三种不同的硫醇修饰的 PEG（平均分子量 (MW)、900、1500 和 5000 g mol(-1)）、四种粒径（10、20、30 和 60 nm）以及两种细胞靶向肽。我们发现纳米颗粒的稳定性随着 PEG 长度的增加、纳米颗粒直径的减小和 PEG 摩尔分数的增加而增加。组装顺序也在纳米颗粒稳定性中发挥作用。通过顺序添加 PEG，然后添加肽制备的混合单层比通过同时共吸附制备的颗粒更稳定。最后，使用电感耦合等离子体发射光谱法 (ICP-OES) 定量了混合 PEG/RME（RME = 受体介导的内吞作用）肽单层修饰的纳米颗粒靶向 HeLa 细胞细胞质的能力。尽管预计与 MW 900 PEG 相比，MW 5000 g mol(-1) PEG 会在空间上阻止肽进入细胞膜，但用混合肽/PEG 5000 单层修饰的纳米颗粒的内化效率与含有混合肽/PEG 900 单层的纳米颗粒一样有效。这些研究可以为能够内化到细胞中的稳定肽/金纳米粒子生物缀合物的组装提供有用的线索。
Gold nanoparticles have shown great promise as therapeutics, therapeutic delivery vectors, and intracellular imaging agents. For many biomedical applications, selective cell and nuclear targeting are desirable, and these remain a significant practical challenge in the use of nanoparticles in vivo. This challenge is being addressed by the incorporation of cell-targeting peptides or antibodies onto the nanoparticle surface, modifications that frequently compromise nanoparticle stability in high ionic strength biological media. We describe herein the assembly of poly(ethylene glycol) (PEG) and mixed peptide/PEG monolayers on gold nanoparticle surfaces. The stability of the resulting bioconjugates in high ionic strength media was characterized as a function of nanoparticle size, PEG length, and monolayer composition. In total, three different thiol-modified PEGs (average molecular weight (MW), 900, 1500, and 5000 g mol(-1)), four particle diameters (10, 20, 30, and 60 nm), and two cell-targeting peptides were explored. We found that nanoparticle stability increased with increasing PEG length, decreasing nanoparticle diameter, and increasing PEG mole fraction. The order of assembly also played a role in nanoparticle stability. Mixed monolayers prepared via the sequential addition of PEG followed by peptide were more stable than particles prepared via simultaneous co-adsorption. Finally, the ability of nanoparticles modified with mixed PEG/RME (RME = receptor-mediated endocytosis) peptide monolayers to target the cytoplasm of HeLa cells was quantified using inductively coupled plasma optical emission spectrometry (ICP-OES). Although it was anticipated that the MW 5000 g mol(-1) PEG would sterically block peptides from access to the cell membrane compared to the MW 900 PEG, nanoparticles modified with mixed peptide/PEG 5000 monolayers were internalized as efficiently as nanoparticles containing mixed peptide/PEG 900 monolayers. These studies can provide useful cues in the assembly of stable peptide/gold nanoparticle bioconjugates capable of being internalized into cells.