In this study, drug-in-cyclodextrin-in-liposomes encapsulating two essential oils (Lippia sidoides and Syzygium aromaticum) and their respective major compounds (thymol and eugenol) were produced by ethanol injection and freeze-dried to form proliposomes using HPBCD and further physicochemically characterized. Despite presenting challenges in the production stage, the inclusion of more than one bioactive (or more than one EO) has the possibility of a producing a synergistic effect and can potentially reduce the dose required for single drug usage with increased drug-efficacy, and subsequently lower drug toxicity.
Liposomes showed high physical stability over one month of storage at 4 °C, with slight changes in the mean size, polydispersity index (PDI), and zeta potential. Reconstituted proliposomes showed a mean size between 350 and 3300 nm, PDI from 0.29 to 0.41, and zeta potential between −22 and −26 mV. Differential scanning calorimetry and X-ray diffraction of proliposomes revealed a less-ordered crystalline structure, leading to high retention of the major bioactive compounds (between 73% and 93% for eugenol, and 74% and 84% for thymol). This work highlights the advantages of using drug-in-cyclodextrin-in-liposomes as delivery systems to retain volatile compounds, increasing their physicochemical stability and their promising potential to be utilized as carriers in products in the pharmaceutical, food, and cosmetic industries.
Baldim, I.; Oliveira, A.M.; Souto, E.B.; Oliveira, W.P. Cyclodextrins-in-Liposomes: A Promising Delivery System for Lippia sidoides and Syzygium aromaticum Essential Oils. Life 2022, 12, 95. https://doi.org/10.3390/life12010095