Recent decades have witnessed several nanocrystal-based hydrophobic drug formulations because of their excellent performance in improving drug loading and controlling drug release as mediate drug forms in tablets or capsules. However, the intravenous administration of drug nanocrystals was usually hampered by their hydrophobic surface properties, causing short half-life time in circulation and low drug distribution in tumor. Here, we proposed to enclose nanocrystals (NC) of hydrophobic drug, such as paclitaxel (PTX) into erythrocyte membrane (EM). By a series of formulation optimizations, spherical PTX nanoparticles (PN) with the particle size of around 280 nm were successfully cloaked in erythrocyte membrane, resulting in a PTX-NP-EM (PNM) system. The PNM could achieve high drug loading of PTX (>60%) and stabilize the particle size significantly compared to PN alone. Besides, the fluorescence-labeling PNM presented better tumor cell uptake, stronger cytotoxicity, and higher drug accumulation in tumor compared to PN. Finally, the PNM was found to be the most effective against tumor growth among all PTX formulations in tumor-bearing mice models, with much lower system toxicity than control formulation. In general, the PNM system with high drug-loading as well as superior bio-distributions in vivo could be served as a promising formulation.

中文翻译：

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模拟红细胞的紫杉醇纳米颗粒，可改善疏水性药物的生物分布，从而增强抗肿瘤功效。

最近几十年见证了几种基于纳米晶体的疏水性药物制剂，因为它们在改善药物载量和控制以片剂或胶囊形式的药物形式释放药物方面表现出色。然而，药物纳米晶体的静脉内给药通常由于其疏水性的表面特性而受阻，导致循环中半衰期短和肿瘤中药物分布低。在这里，我们建议将诸如紫杉醇（PTX）等疏水性药物的纳米晶体（NC）封装在红细胞膜（EM）中。通过一系列配方优化，将粒径约280 nm的球形PTX纳米颗粒（PN）成功掩盖在红细胞膜中，形成了PTX-NP-EM（PNM）系统。PNM可以实现PTX的高载药量（> 与单独使用PN相比，其颗粒大小稳定在60％左右），并显着稳定了粒径。此外，与PN相比，荧光标记的PNM表现出更好的肿瘤细胞摄取，更强的细胞毒性和更高的肿瘤累积量。最后，在荷瘤小鼠模型中，PNM被发现在所有PTX制剂中对肿瘤生长最有效，其系统毒性比对照制剂低得多。总的来说，具有高载药量以及体内生物分布优越的PNM系统可以作为一种有前途的配方。具有比对照制剂低得多的系统毒性。总的来说，具有高载药量以及体内生物分布优越的PNM系统可以作为一种有前途的配方。具有比对照制剂低得多的系统毒性。总的来说，具有高载药量以及体内生物分布优越的PNM系统可以作为一种有前途的配方。