Luteolin (3′,4′,5,7-tetrahydroxyflavone), a type of flavonoid found in medicinal herbs and vegetables, has been of great interest due to its antioxidative, anti-inflammatory, and anticarcinogenic effects. Despite these beneficial biological properties, the ease with which luteolin forms molecular crystals in conventional aqueous formulations has hampered much wider applications. In this study, we introduce an oil-in-water (O/W) nanoemulsion vehicle system for enhanced follicular delivery of luteolin. The luteolin-loaded nanoemulsion, which had an average hydrodynamic size of approximately 290 nm, was produced by the assembly of poly(ethylene oxide)-block-poly(ε-caprolactone) and lecithin at the O/W interface. The luteolin-loaded nanoemulsion showed outstanding stability against drop coalescence and aggregation. This was confirmed from the slight drop size increase after repeated freeze–thaw cycling and long-term storage. Moreover, in vivo hair growth evaluation demonstrated that the luteolin-loaded nanoemulsions fabricated in this study possessed the hair growth-promotion activity, which is comparable with the case of using a luteolin solution in an organic solvent.

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纳米乳液载体作为木犀草素卵泡输送的载体

木犀草素（3'，4'，5,7-四羟基黄酮）是一种存在于草药和蔬菜中的类黄酮，由于其抗氧化，抗炎和抗癌作用而备受关注。尽管具有这些有益的生物学特性，木犀草素在常规水性制剂中形成分子晶体的难易程度阻碍了更广泛的应用。在这项研究中，我们介绍了水包油（O / W）纳米乳剂载体系统，用于增强木犀草素的卵泡输送。通过组装聚（环氧乙烷）嵌段生产出具有木犀草素负载的纳米乳液，其平均流体动力学尺寸约为290 nm。-O（W）界面的聚（ε-己内酯）和卵磷脂。负载木犀草素的纳米乳液对液滴的聚结和聚集表现出出色的稳定性。反复的冻融循环和长期储存后，液滴尺寸会略有增加，从而证实了这一点。此外，体内毛发生长评估表明，在该研究中制备的负载木犀草素的纳米乳剂具有促进毛发生长的活性，这与在有机溶剂中使用木犀草素溶液的情况相当。