Quantification of Spontaneous W/O Emulsification and its Impact on the Swelling Kinetics of Multiple W/O/W Emulsions

Bahtz, Jana; Gunes, Deniz Z.; Syrbe, Axel; Mosca, Nicola; Fischer, Peter; Windhab, Erich J.

doi:10.1021/acs.langmuir.6b00425

Cited by 50 publications

(60 citation statements)

References 54 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Block‐copolymer surfactants have been shown to transport encapsulants across the oil phase either by forming inverse micelles or small aqueous drops . These tests have always been performed on emulsions stabilized with uncharged, unfunctionalized block‐copolymer surfactants.…”

Section: Resultsmentioning

confidence: 99%

“…Significant amounts of hydrophilic reagents have been shown to be transported across surfactant‐containing oil phases even if they have a very low solubility . This transport has been assigned to the spontaneous formation of micelles or small aqueous drops . To understand the reason for the pH‐dependence of this transport, we measure the formation of such transport vehicles in bulk.…”

Section: Resultsmentioning

confidence: 99%

“…Indeed, double emulsions are frequently employed to store and deliver reagents, as picoliter‐sized reaction vessels to conduct chemical and biochemical reactions, or as templates to produce microcapsules . Certain surfactant‐stabilized double emulsions are permeable toward hydrophilic encapsulants, even though their solubility in the oil phase is very low . These double emulsions allow passive exchange of reagents.…”

Section: Introductionmentioning

confidence: 99%

See 2 more Smart Citations

Selectively Permeable Double Emulsions

Ong

Amstad

2019

Small

View full text Add to dashboard Cite

Natural organisms are made of different types of microcompartments, many of which are enclosed by cell membranes. For these organisms to display a proper function, the microcompartments must be selectively permeable. For example, cell membranes are typically permeable toward small, uncharged molecules such as water, selected nutrients, and cell signaling molecules, but impermeable toward many larger biomolecules. Here, it is reported for the first time dynamic compartments, namely surfactant‐stabilized double emulsions, that display selective and tunable permeability. Selective permeability is imparted to double emulsions by stabilizing them with catechol‐functionalized surfactants that transport molecules across the oil shell of double emulsions only if they electrostatically or hydrophobically attract encapsulants. These double emulsions are employed as semipermeable picoliter‐sized vessels to controllably perform complexation reactions inside picoliter‐sized aqueous cores. This thus far unmet level of control over the transport of reagents across oil phases opens up new possibilities to use double emulsion drops as dynamic and selectively permeable microcompartments to initiate and maintain chemical and biochemical reactions in picoliter‐sized cell‐mimetic compartments.

show abstract

Section: Resultsmentioning

confidence: 99%

Section: Resultsmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

See 1 more Smart Citation

Selectively Permeable Double Emulsions

Ong

Amstad

2019

Small

View full text Add to dashboard Cite

show abstract

“…Over the years, a lot of research has been conducted on W/O/W emulsion stability with special attention to diffusion‐driven molecular transport and to the unveiling of the underlying mechanisms governing this type of destabilization . Next to diffusion of single molecules, diffusion‐mediated transport has been described in literature .…”

Section: Introductionmentioning

confidence: 99%

“…Next to diffusion of single molecules, diffusion‐mediated transport has been described in literature . Four assisted transport mechanisms have been defined in case of water transport, that is, transport through spontaneous emulsification, reversed micelles, thinned lamellae, and hydrated surfactants . Most of the studies regarding quantification of the (water) transport kinetics illustrate the importance of the W/O/W formulation and focus mainly on osmotic regulation, emulsifier characteristics and concentrations, or on the physical state of matter of the internal water droplets (e.g., gelation of the internal water).…”

Section: Introductionmentioning

confidence: 99%

Fat crystals: A tool to inhibit molecular transport in W/O/W double emulsions

Nelis

Declerck

Vermeir

et al. 2019

Magnetic Reson in Chemistry

View full text Add to dashboard Cite

Water‐in‐oil‐in‐water (W/O/W) double emulsions are a promising technology for encapsulation applications of water soluble compounds with respect to functional food systems. Yet molecular transport through the oil phase is a well‐known problem for liquid oil‐based double emulsions. The influence of network crystallization in the oil phase of W/O/W globules was evaluated by NMR and laser light scattering experiments on both a liquid oil‐based double emulsion and a solid fat‐based double emulsion. Water transport was assessed by low‐resolution NMR diffusometry and by an osmotically induced swelling or shrinking experiment, whereas manganese ion permeation was followed by means of T2‐relaxometry. The solid fat‐based W/O/W globules contained a crystal network with about 80% solid fat. This W/O/W emulsion showed a reduced molecular water exchange and a slower manganese ion influx in the considered time frame, whereas its globule size remained stable under the applied osmotic gradients. The reduced permeability of the oil phase is assumed to be caused by the increased tortuosity of the diffusive path imposed by the crystal network. This solid network also provided mechanical strength to the W/O/W globules to counteract the applied osmotic forces.

show abstract

Designing Semipermeable Hydrogel Shells with Controlled Thickness through Internal Osmosis in Triple‐Emulsion Droplets

Lee

Che

Tai

et al. 2021

Adv Funct Materials

View full text Add to dashboard Cite

Hydrogel shells that compartmentalize the water core from the aqueous surrounding provide molecular selectivity on size and charge in transmembrane transport. It is highly demanding to produce thin hydrogel shells to minimize diffusion length and maximize core volume. Here, internal osmosis in water-in-oil-in-water-in-oil (W/O/W/O) triple-emulsion droplets is used to produce thin hydrogel shells enclosing a large water core. The triple-emulsion droplets are prepared to have an ultrathin middle oil layer using a capillary microfluidic device. The innermost water droplet has a higher osmolarity than the outer water layer containing photopolymerizable hydrogel precursors, which pumps water from the outer layer to the core through the ultrathin oil layer by the osmosis. Therefore, the outer layer gets thinner and hydrogel precursors are enriched while the size of the triple-emulsion droplets remains unchanged. Through photopolymerization of precursors and phase transfer from oil to water, hydrogel shells enclosing water core are produced in the water environment; the oil layer is ruptured for molecular exchange through the shells. The thickness and composition of the hydrogel shells are precisely controllable by the osmotic conditions. The shells show a high permeation rate due to the thinness as well as controlled cut-off threshold of permeation for neutral and charged molecules.

show abstract

Quantification of Spontaneous W/O Emulsification and its Impact on the Swelling Kinetics of Multiple W/O/W Emulsions

Cited by 50 publications

References 54 publications

Selectively Permeable Double Emulsions

Selectively Permeable Double Emulsions

Fat crystals: A tool to inhibit molecular transport in W/O/W double emulsions

Designing Semipermeable Hydrogel Shells with Controlled Thickness through Internal Osmosis in Triple‐Emulsion Droplets

Contact Info

Product

Resources

About