Research Group BIO-190, Department of Microbiology, University of Granada, Spain.
Int J Pharm. 2011 Dec 15;421(2):321-31. doi: 10.1016/j.ijpharm.2011.09.042. Epub 2011 Oct 1.
The aim of this study was to use archaeosomes, a novel kind of liposomes made up by archaeal polar lipids, both multilamellars (MLVs) and unilamellars (SUVs), as a topical delivery system for natural antioxidant compounds recovered from olive mill waste. For comparative purpose an analogue formulation of phosphatidylcholine liposomes was prepared. SUVs were smaller than MLVs ones, showing size values smaller than 200nm, which was maintained during the stability study. Transmission electron microscopy showed spherical morphology for conventional liposomes while archaeosomes had more irregular membranes. Vesicle encapsulation efficiency was quite similar in both formulations and was enough to ensure a good antioxidant activity. Stability studies were performed one month after the preparation of formulations, which showed a high stability with no change in the initial characteristics of the suspensions. Furthermore, the possibility of incorporating the liposomal suspensions in different excipients (Carbopol-940(®) and Pluronic-127(®)) for topical administration was studied. In order to evaluate the release behaviour of the different systems prepared, in vitro diffusion studies were carried out using vertical diffusion Franz cells. In both cases the incorporation of the vesicles into the gels lead in a sustained release for 24h. Archaeosome gels released a similar amount of phenolic compounds regardless the excipient used, while in liposomal gels great release differences were found between carbopol and pluronic gel.
本研究旨在利用 archaeosomes（一种由古菌极性脂质组成的新型脂质体，包括多分子层囊泡（MLVs）和单分子层囊泡（SUVs））作为从橄榄厂废物中回收的天然抗氧化化合物的局部递药系统。为了进行比较，还制备了一种类似的磷脂质脂质体模拟制剂。SUVs 比 MLVs 小，粒径值小于 200nm，在稳定性研究期间保持不变。透射电子显微镜显示常规脂质体具有球形形态，而 archaeosomes 具有更不规则的膜。两种制剂的囊泡包封效率非常相似，足以确保良好的抗氧化活性。稳定性研究在制剂制备一个月后进行，结果表明制剂具有很高的稳定性，悬浮液的初始特性没有变化。此外，还研究了将脂质体悬浮液掺入不同赋形剂（Carbopol-940(®)和 Pluronic-127(®)）中进行局部给药的可能性。为了评估不同体系的释放行为，使用垂直扩散 Franz 细胞进行了体外扩散研究。在这两种情况下，将囊泡掺入凝胶中都会导致 24 小时内的持续释放。无论使用何种赋形剂，archaeosome 凝胶释放的酚类化合物量相似，而在脂质体凝胶中，Carbopol 和 Pluronic 凝胶之间存在很大的释放差异。
