Cationic polymers exhibit high cytotoxicity via strong interaction with cell membranes. To reduce cell membrane damage, a hydrophilic polymer is introduced to the cationic nanoparticle surface. The hydrophilic polymer coating of cationic nanoparticles resulted in a nearly neutral nanoparticle. These particles are applied to mouse fibroblast (3T3) and human cervical adenocarcinoma (Hela) cells. Interestingly, nanoparticles with a long cationic segment decrease cell activity regardless of cell type, while those with a short segment only affect 3T3 cell activity at lower concentrations less than 500 µg mL⁻¹. Most nanoparticles are located inside 3T3 cells but on the cell membrane of Hela cells. The short cationic nanoparticle shows negligible cell membrane damage despite its high accumulation on Hela cell membranes. Cell activity changed by hydrophilic polymer‐coated cationic nanoparticles is caused by incorporated nanoparticle accumulation in the cells, not cell membrane damage. To suppress the cytotoxicity from the cationic polymer, cationic nanoparticle needs to completely cover with hydrophilic polymer so as not to exhibit the cationic effect and applies to cell with low concentrations to reduce the nonselective cytotoxicity from the cationic polymer.

中文翻译：

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用亲水聚合物覆盖的阳离子纳米粒子选择性控制细胞活性。

阳离子聚合物通过与细胞膜的强相互作用表现出高细胞毒性。为了减少细胞膜损伤，将亲水性聚合物引入阳离子纳米颗粒表面。阳离子纳米颗粒的亲水性聚合物涂层产生近乎中性的纳米颗粒。这些颗粒应用于小鼠成纤维细胞（3T3）和人宫颈腺癌（Hela）细胞。有趣的是，具有长阳离子片段的纳米颗粒无论细胞类型如何都会降低细胞活性，而具有短阳离子片段的纳米颗粒仅在低于500 µg mL ^-1的较低浓度下才影响3T3细胞活性。。大多数纳米颗粒位于3T3细胞内部，但在Hela细胞的细胞膜上。短的阳离子纳米颗粒尽管在Hela细胞膜上有很高的积累，却显示出可忽略的细胞膜损伤。亲水性聚合物涂覆的阳离子纳米颗粒改变的细胞活性是由于细胞中掺入的纳米颗粒积累而不是细胞膜损伤引起的。为了抑制来自阳离子聚合物的细胞毒性，阳离子纳米颗粒需要完全被亲水性聚合物覆盖以不表现出阳离子作用，并应用于低浓度的细胞以减少来自阳离子聚合物的非选择性细胞毒性。