Purpose

Captopril is one of the most important angiotensin converting enzyme inhibitors and still the gold standard for the treatment of hypertension and congestive heart failure. However, it has a short duration of action and about 1–2 h biological half-life. Formulation of a sustained release dosage form of captopril is difficult due to its instability at the alkaline pH of the gastrointestinal tract. Therefore, incorporation of captopril within bioadhesive cubic nanoparticles or cubosomes could be an alternative way to improve its efficiency.

Methods

Monoolein dispersions containing captopril were prepared by the homogenization technique using different concentrations of monoolein and poloxamer. Characterization of these dispersions was performed by measuring particle size, small angle X-ray diffraction, cryo transmission electron microscopy, entrapment efficiency, and in-vitro release of captopril.

Results

Monoolein cubic nanoparticles with mean particle sizes between 250 and 350 nm were obtained after autoclaving the homogenized dispersions. The cubic structure was confirmed by the presence of the three characteristic X-ray diffraction peaks of P-type cubic phase and from cryo transmission pictures. A slow release of captopril from cubosomes was observed within 8 h with a high bioadhesion capacity where about 75% of these cubosomes adhered to stomach tissues.

Conclusion

Monoolein cubosomes could be used successfully as carriers for captopril where they slowly released it and had a good adhesion property to stomach tissues.

中文翻译：

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作为卡托普利载体的生物粘附性单油精长方体的制备和表征

目的

卡托普利是最重要的血管紧张素转换酶抑制剂之一，仍然是治疗高血压和充血性心力衰竭的金标准。然而，它的作用持续时间短，生物半衰期约为 1-2 小时。卡托普利缓释剂型的配制很困难，因为它在胃肠道的碱性 pH 值下不稳定。因此，将卡托普利掺入生物粘附性立方纳米颗粒或立方体中可能是提高其效率的一种替代方法。

方法

使用不同浓度的单油精和泊洛沙姆通过均质化技术制备含有卡托普利的单油精分散体。通过测量粒度、小角 X 射线衍射、低温透射电子显微镜、截留效率和卡托普利的体外释放来表征这些分散体。

结果

在对均质分散体进行高压灭菌后，获得了平均粒径在 250 和 350 nm 之间的单油精立方纳米颗粒。立方结构通过存在 P 型立方相的三个特征 X 射线衍射峰和低温透射图片来证实。在 8 小时内观察到卡托普利从立方体中缓慢释放，具有高生物粘附能力，其中约 75% 的这些立方体粘附在胃组织上。

结论

Monoolein cuosomes 可以成功地用作卡托普利的载体，它们可以缓慢释放卡托普利，并且对胃组织具有良好的粘附性。