Eucalyptol (Euc) is a natural monoterpene with insecticide effects. Being highly volatile and sensitive to ambient conditions, its encapsulation would enlarge its application. Euc‐loaded conventional liposomes (CL), cyclodextrin/drug inclusion complex, and drug‐in‐cyclodextrin‐in‐liposomes (DCL) are prepared to protect Euc from degradation, reduce its evaporation, and provide its controlled release. The liposomal suspension is freeze‐dried using hydroxypropyl‐β‐cyclodextrin (HP‐β‐CD) as cryoprotectant. The liposomes are characterized before and after freeze‐drying. The effect of Euc on the fluidity of liposomal membrane is also examined. A release study of Euc from delivery systems, in powder and reconstituted forms, is performed by multiple head extraction at 60 °C after 6 months of storage at 4 °C. CL and DCL suspensions are homogeneous, show nanometric vesicles size, spherical shape, and negative surface charge before and after freeze‐drying. Moreover, HP‐β‐CD does not affect the fluidity of liposomes. CL formulations present a weak encapsulation for Euc. The loading capacity of eucalyptol in DCL is 38 times higher than that in CL formulation. In addition, freeze‐dried DCL and HP‐β‐CD/Euc inclusion complex show a higher retention of eucalyptol than CL delivery system. Both carrier systems HP‐β‐CD/Euc and Euc‐loaded DCL decrease Euc evaporation and improve its retention. Practical Applications: Eucalyptol is a natural insecticide. It is highly volatile and poorly soluble in water. To enlarge its application, its encapsulation in three delivery systems (conventional liposomes, cyclodextrin/drug inclusion complex, combined system composed of cyclodextrin inclusion complex and liposome) is studied. In this paper it is proved that cyclodextrin/eucalyptol inclusion complex and eucalyptol‐in‐cyclodextrin‐in‐liposome are effective delivery systems for encalyptol encapsulation, retention, and release.

中文翻译：

---

在基于羟丙基-β-环糊精和脂质体的递送系统中保留桉树油，一种天然挥发性杀虫剂

桉油精（Euc）是一种具有杀虫作用的天然单萜。由于高度挥发性和对环境条件敏感，其封装将扩大其应用。制备载有 Euc 的常规脂质体 (CL)、环糊精/药物包合物和药物-环糊精-脂质体 (DCL) 以保护 Euc 免于降解、减少其蒸发并提供其控制释放。脂质体悬浮液使用羟丙基-β-环糊精（HP-β-CD）作为冷冻保护剂进行冷冻干燥。在冷冻干燥之前和之后表征脂质体。还检查了 Euc 对脂质体膜流动性的影响。在 4 °C 下储存 6 个月后，通过在 60 °C 下多头提取进行 Euc 从递送系统中的释放研究，以粉末和重构形式进行。CL 和 DCL 悬浮液是均质的，显示冷冻干燥前后的纳米囊泡大小、球形和负表面电荷。此外，HP-β-CD 不影响脂质体的流动性。CL 配方对 Euc 的封装较弱。桉叶油素在 DCL 中的负载能力是 CL 配方中的 38 倍。此外，冷冻干燥的 DCL 和 HP-β-CD/Euc 包合物显示出比 CL 递送系统更高的桉树油保留率。载体系统 HP-β-CD/Euc 和 Euc 负载的 DCL 都减少了 Euc 蒸发并提高了其保留率。实际应用： 桉油精是一种天然杀虫剂。它极易挥发，难溶于水。为了扩大其应用，将其封装在三种递送系统（常规脂质体、环糊精/药物包合物、研究了由环糊精包合物和脂质体组成的组合系统。本文证明环糊精/桉油精包合物和桉油精-环糊精-脂质体是用于环糊精包封、保留和释放的有效递送系统。