The effective use of fusion inhibitor peptides against cervical and colorectal infections requires the development of sustained release formulations. In this work we comparatively study two different formulations based on polymeric nanoparticles and lipid vesicles to propose a suitable delivery nanosystem for releasing an HIV-1 fusion inhibitor peptide in vaginal mucosa. Polymeric nanoparticles of poly-d,l-lactic-co-glycolic acid (PLGA) and lipid large unilamellar vesicles loaded with the inhibitor peptide were prepared. Both formulations showed average sizes and polydispersity index values corresponding to monodisperse systems appropriate for vaginal permeation. High entrapment efficiency of the inhibitor peptide was achieved in lipid vesicles, which was probably due to the peptide’s hydrophobic nature. In addition, both nanocarriers remained stable after two weeks stored at 4 °C. While PLGA nanoparticles (NPs) did not show any delay in peptide release, lipid vesicles demonstrated favorably prolonged release of the peptide. Lipid vesicles were shown to improve the retention of the peptide on ex vivo vaginal tissue in a concentration sufficient to exert its pharmacological effect. Thus, the small size of lipid vesicles, their lipid-based composition as well as their ability to enhance peptide penetration on vaginal tissue led us to consider this formulation as a better nanosystem than polymeric nanoparticles for the sustained delivery of the HIV-1 fusion inhibitor peptide in vaginal tissues.

中文翻译：

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脂质囊泡装载有 HIV-1 融合抑制肽作为潜在的杀微生物剂。


有效使用融合抑制肽对抗宫颈和结肠直肠感染需要开发缓释制剂。在这项工作中，我们比较研究了基于聚合物纳米粒子和脂质囊泡的两种不同制剂，以提出一种合适的递送纳米系统，用于在阴道粘膜中释放 HIV-1 融合抑制肽。制备了聚d ， l-乳酸-乙醇酸共聚物（PLGA）的聚合物纳米颗粒和负载抑制剂肽的脂质大单层囊泡。两种制剂均显示出与适合阴道渗透的单分散系统相对应的平均尺寸和多分散指数值。在脂质囊泡中实现了抑制肽的高包封效率，这可能是由于肽的疏水性。此外，两种纳米载体在 4°C 保存两周后仍保持稳定。虽然 PLGA 纳米粒子 (NP) 没有表现出肽释放的任何延迟，但脂质囊泡显示出有利地延长肽的释放。研究表明，脂质囊泡可以改善肽在离体阴道组织上的保留，其浓度足以发挥其药理作用。因此，脂质囊泡的小尺寸、其基于脂质的成分以及增强肽在阴道组织上渗透的能力使我们认为该制剂是比聚合物纳米颗粒更好的纳米系统，可用于持续递送 HIV-1 融合抑制剂阴道组织中的肽。