Cross-talk between emulsion drops: how are hydrophilic reagents transported across oil phases?

Etienne, Gianluca; Vian, Antoine; Biočanin, Marjan; Deplancke, Bart; Amstad, Esther

doi:10.1039/c8lc01000e

Cited by 49 publications

(66 citation statements)

References 70 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…We cannot measure any significant change in interfacial tension upon variations in pH, as shown in Figure S2 (Supporting Information). These results suggest that the pH‐dependent fluorescein transport is indeed caused by the pH‐dependent intermolecular interactions between fluorescein and the surfactants, and not by surface tension effects …”

Section: Resultsmentioning

confidence: 77%

“…Surfactant‐stabilized double emulsions have been shown to display a pH‐dependent permeability . To assess if this is also the case for double emulsions stabilized with catechol‐functionalized diblock copolymer surfactants, we produce FSH‐ED900‐HA‐stabilized double emulsions that contain fluorescein, a pH‐responsive fluorophore, in their cores.…”

Section: Resultsmentioning

confidence: 99%

“…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%

“…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%

“…These double emulsions allow passive exchange of reagents. However, such exchanges are difficult to control and often hamper the use of emulsions as tight containers . To improve the control over the reagent transport, surfactants that respond to stimuli, such as changes in pH and the presence of certain salts, have been developed .…”

Section: Introductionmentioning

confidence: 99%

See 4 more Smart Citations

Selectively Permeable Double Emulsions

Ong

Amstad

2019

Small

Self Cite

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: 77%

Section: Resultsmentioning

confidence: 99%

Section: Resultsmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

See 3 more Smart Citations

Selectively Permeable Double Emulsions

Ong

Amstad

2019

Small

Self Cite

View full text Add to dashboard Cite

show abstract

Microfluidic Fabrication of Capsule Sensor Platform with Double‐Shell Structure

Lee

Kim

et al. 2019

Adv Funct Materials

View full text Add to dashboard Cite

Metal nanoparticles are frequently employed for the colorimetric detection of specific target molecules using an aggregation‐induced shift of the localized surface plasmon resonance. However, metal nanoparticles dispersed in bulk solutions are prone to be contaminated by adhesive molecules and the dispersions tend to be diluted by sample fluids, restricting direct application to unpurified pristine samples. Here, a versatile capsule sensor platform is proposed that can encompass a variety of different types of nanoparticle‐based sensors. The capsule sensors are microfluidically prepared to obtain close control over their dimensions and composition. Their aqueous cores that are loaded with sensing materials are surrounded by an ultrathin inner oil shell and an outer hydrogel shell. The hydrogel shell prevents the diffusion of large adhesive molecules into the core, thereby preventing contamination of the sensing materials. The oil shell is selectively permeable such that it further improves the sensor selectivity. Importantly, these shells confine the sensing materials and prevent them from being diluted, securing a consistent optical property. Moreover, the capsule‐based sensors display a higher sensitivity than bulk dispersions because a smaller amount of sensing materials is used. The power of nanoparticle‐loaded capsule sensors is demonstrated using lysine‐coated gold nanoparticles to detect mercury ions.

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

Cross-talk between emulsion drops: how are hydrophilic reagents transported across oil phases?

Cited by 49 publications

References 70 publications

Selectively Permeable Double Emulsions

Selectively Permeable Double Emulsions

Microfluidic Fabrication of Capsule Sensor Platform with Double‐Shell Structure

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

Contact Info

Product

Resources

About