Background

A novel phosphatidyl nanoprodrug system can be selectively released parent drugs in cancer cells, triggered by the local overexpression of phospholipase D (PLD). This system significantly reduces the intrinsic disadvantages of conventional chemotherapeutic drugs. However, the separation and purification processes of phosphatidyl prodrug, the precursor of phosphatidyl nanoprodrug, have not been established, and the preparation of nanocrystals with good stability and tumor-targeting capability is still challenging.

Results

In this study, we established a successive elution procedure for the phosphatidyl prodrug—phosphatidyl mitoxantrone (PMA), using an initial ten-bed volume of chloroform/methanol/glacial acetic acid/water (26/10/0.8/0.7) (v/v/v/v) followed by a five-bed volume (26/10/0.8/3), with which purity rates of 96.93% and overall yields of 50.35% of PMA were obtained. Moreover, to reduce the intrinsic disadvantages of conventional chemotherapeutic drugs, phosphatidyl nanoprodrug—PMA nanoprodrug (NP@PMA)—was prepared. To enhance their stability, nanoparticles were modified with polyethylene glycol (PEG). We found that nanoprodrugs modified by PEG (NP@PEG–PMA) were stably present in RPMI-1640 medium containing 10% FBS, compared with unmodified nanoprodrug (NP@PMA). To enhance active tumor-targeting efficiency, we modified nanoparticles with an arginine-glycine-aspartic acid (RGD) peptide (NP@RGD–PEG–PMA). In vitro cytotoxicity assays showed that, compared with the cytotoxicity of NP@PEG–PMA against tumor cells, that of NP@RGD–PEG–PMA was enhanced. Thus, RGD modification may serve to enhance the active tumor-targeting efficiency of a nanoprodrug, thereby increasing its cytotoxicity.

Conclusions

A process for the preparation and purification of novel phosphatidyl prodrugs was successfully established, and the nanoprodrug was modified using PEG for enhanced nanoparticle stability, and using RGD peptide for enhanced active tumor-targeting efficiency. These procedures offer considerable potential in the development of functional antitumor prodrugs.

中文翻译：

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新型磷脂酰前药的制备与纯化及磷脂酰纳米前药的性能调节

背景

通过磷脂酶D（PLD）的局部过度表达，可以在癌细胞中选择性释放一种新型磷脂酰纳米前药系统。该系统显着减少了常规化疗药物的固有缺点。然而，尚未建立磷脂酰纳米前药的前体磷脂酰前药的分离和纯化工艺，制备具有良好稳定性和肿瘤靶向能力的纳米晶体仍然具有挑战性。

结果

在这项研究中，我们建立了一个连续的洗脱程序，用于磷脂酰前药-磷脂酰米托蒽醌（PMA），使用的初始床层体积为十倍床的氯仿/甲醇/冰醋酸/水（26/10 / 0.8 / 0.7）（v / v / v / v），然后是五张床的体积（26/10 / 0.8 / 3），其纯度为96.93％，PMA的总收率为50.35％。此外，为了减少常规化学治疗药物的固有缺点，制备了磷脂酰纳米前药-PMA纳米前药（NP @ PMA）。为了增强其稳定性，用聚乙二醇（PEG）修饰了纳米颗粒。我们发现，与未修饰的纳米前药（NP @ PMA）相比，经PEG修饰的纳米前药（NP @ PEG-PMA）在含有10％FBS的RPMI-1640培养基中稳定存在。为了提高主动靶向肿瘤的效率，我们用精氨酸-甘氨酸-天冬氨酸（RGD）肽（NP @ RGD–PEG–PMA）修饰了纳米颗粒。体外细胞毒性试验表明，与NP @ PEG-PMA对肿瘤细胞的细胞毒性相比，NP @ RGD-PEG-PMA的细胞毒性得到了增强。因此，RGD修饰可用于增强纳米前药的活性肿瘤靶向效率，从而增加其细胞毒性。

结论

成功建立了制备和纯化新型磷脂酰前药的方法，并使用PEG修饰了纳米前药以增强纳米颗粒的稳定性，并使用RGD肽修饰了活性肿瘤的靶向效率。这些程序为功能性抗肿瘤前药的开发提供了巨大的潜力。