Efficient attachment of magnetic nanoparticles to cell membranes plays an important role in the activation of cell membrane channels. Streptavidin (SA) was successfully modified to Poly (ethylene imine) (PEI)-superparamagnetic iron oxide nanoparticles (SPIONs) to form SA/PEI-SPIONs, which have high colloidal stability and low cytotoxicity. The SA/PEI-SPIONs were incubated with PC-12 cells which had first been cultured in a Roswell Park Memorial Institute medium 1640 containing 0.2 mg l −1 biotin for 12 h. The cells were observed by transmission electron microscopy, and the nanoparticles were clearly attached on the cell membrane, which can be attributed to the specific binding between the SA and biotin sites on the cell surface. This work provides a simple way to attach SA-modified nanoparticles on the membranes of cells by only culturing cells in a biotin-containing medium. This work makes possible biomedical applications that require nanoparticles to target cell memb...

中文翻译：

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链霉亲和素修饰的超顺磁性氧化铁纳米颗粒附着在 PC-12 细胞膜上。

磁性纳米粒子与细胞膜的有效附着在细胞膜通道的激活中起着重要作用。链霉亲和素（SA）被成功修饰为聚（乙烯亚胺）（PEI）-超顺磁性氧化铁纳米粒子（SPIONs），形成具有高胶体稳定性和低细胞毒性的SA/PEI-SPIONs。SA/PEI-SPION 与 PC-12 细胞一起孵育，PC-12 细胞首先在含有 0.2 mg l -1 生物素的 Roswell Park Memorial Institute 培养基 1640 中培养 12 小时。通过透射电镜观察细胞，纳米颗粒清晰地附着在细胞膜上，这可以归因于SA与细胞表面生物素位点之间的特异性结合。这项工作提供了一种简单的方法，只需在含有生物素的培养基中培养细胞，即可将 SA 修饰的纳米颗粒附着在细胞膜上。这项工作使需要纳米粒子靶向细胞膜的生物医学应用成为可能。