Fabrication of Novel Hierarchical Multicompartment Highly Stable Triple Emulsions for the Segregation and Protection of Multiple Cargos by Spatial Co-encapsulation

Abstract

High-order multiple emulsions are of great interest in both fundamental research and industrial applications as vehicles for their encapsulation capability of actives. In this work, we report a hierarchically multicompartmental highly stable triple emulsion by emulsifying and assembling of natural Quillaja saponin. Water-in-oil-in-(oil-in-water) (W 2 /O 2 /(O 1 /W 1 )) triple emulsion indicates that the compartmented system consisted of surfaced saponin-coated nanodroplets (SNDs) and dispersed oil globules, which in turn contained smaller aqueous droplets. The effects of formulation parameters, including lipophilic emulsifier content, oil fraction, and SND concentration, on the formation of multiple emulsions were systematically investigated. The assembly into fibrillar network of SNDs at the outer oil−water interface effectively protected the triple emulsion droplets against flocculation and coalescence, and strongly prevented the osmotic-driven water diffusion between the internal water droplets and the external water phase, thus contributing to superior stability during 180 days storage. All of these characteristics make the multicompartmentalized emulsions suitable to co-encapsulate a hydrophilic bioactive (gardenia blue) and two hydrophobic bioactives (eapsanthin and curcumin) in a single emulsion droplet hierarchically for the segregation and protection of multiple cargos. This approach offers a promising route toward accessing the next generation of functional deliveries and encapsulation strategies.

Independent co-delivery of model actives with different degrees of hydrophilicity from oil-in-water and water-in-oil emulsions stabilised by solid lipid particles via a Pickering mechanism: a-proof-of-principle study

“…In conclusion, the present proof-of-principle study demonstrates that the approach proposed by Spyropoulos et al [19] can be applied to SLN-stabilised emulsions to enable the co-encapsulation and independent co-delivery of two segregated actives. The current work significantly extends previous research efforts in the area of compartmentalised multi-delivery of actives using liquid-based systems [8,9,17,18], by confirming that the employed co-encapsulation strategy is applicable to both w/o and o/w simple emulsions and can be utilised for the co-delivery of different combinations of actives with varying degrees of hydrophilicity/hydrophobicity. In addition, the current preliminary findings underline the effect of the emulsifier used during fabrication of SLNs on the attainment of different release profiles from the SLN-stabilised Pickering emulsions, a concept that has been previously described only for o/w emulsions [14].…”

“…temperature), and oil-drug interactions [13,15,16]. In terms of co-encapsulation/co-delivery, a triple emulsion (water-in-oil-in-(oil-in-water)) with a highly compartmentalised structure was previously employed for the segregated co-encapsulation of three photosensitive compounds with varying degrees of hydrophilicity, resulting in their improved stability and protection [17]. Winkler et al [18] employed biphasic PLGA/PCL (poly(lactic-co-glycolic acid)/polycaprolactone) Janus particles for the co-encapsulation of either two hydrophobic actives, using a single o/w emulsion method, or a combination of hydrophilic/hydrophobic compounds, using three different methods to enhance the solubility of the hydrophilic active; single o/w emulsion with partially water-miscible solvent, single o/w emulsion using a co-solvent or double w/o/w emulsions.…”

Oil–Water Interfacial-Directed Spontaneous Self-Assembly of Natural Quillaja Saponin for Controlling Interface Permeability in Colloidal Emulsions

“…Furthermore, wrinkling of the aqueous solution containing QS occurred and wrapped outside the oil drop to form the “crosslinked network” (see arrow), which further confirms the self-assembly of QS at the oil–water interface of the adjacent saponin molecules. This led to the locking together by self-assembled crosslinking between the molecules and provided a firm basis for the formation of simultaneously stabilizing emulsions and providing hierarchy comparts. ,, …”

“…This led to the locking together by selfassembled crosslinking between the molecules and provided a firm basis for the formation of simultaneously stabilizing emulsions and providing hierarchy comparts. 18,19,26 A minimization of interfacial free energy between the interface of two immiscible liquids is believed to be the driving force for selfassembly. 27 Presumably the self-assembly of QS absorbing and organizing at the oil−water interface forms a solid-like layer in a closely packed array and "surface skin".…”

“…, nanoemulsion, multicompartment emulsion, and oleogel). These colloids were widely used to deliver health-promoting bioactives in multidisciplinary fields. ,, Despite the numerous actual and wide technological applications, the interface assembly properties of QS and its insight mechanism in emulsion stabilization and excellent functional characteristics have not been clarified at the molecular level.…”