Osmolarity-controlled swelling behaviors of dual-cored double-emulsion drops

  • 520 Accesses

  • 5 Citations


We report osmolarity-controlled swelling behaviors of dual-cored water-in-oil-in-water (W/O/W) double-emulsion drops, which are caused by the discrepancy of salt concentration of the inner cores and suspending medium. The expanding speed and resultant size can be manipulated independently according to salt concentration. The swelling behaviors result in two kinds of transformation in the emulsion drops. One is coalescence of the two inner aqueous cores, taking place when the cores are of the same salt concentrations and the double-emulsion drops swell to dumbbell-shaped morphology. Another is rupture of one inner core, which happens when the cores are of different salt concentrations and the double-emulsion drops swell to snowman-shaped structures. The conditions for core-coalescence and core-rupture are investigated, respectively. The swelling leading transformation of emulsion drops are of promising application as microreactors and tiny vesicles: The core-coalescence can lead to controlled reaction of two solvents while protecting the reaction form external contamination; the core-rupture may be utilized for targeted release of reagents at specific position.

This is a preview of subscription content, log in to check access.

Access options

Buy single article

Instant unlimited access to the full article PDF.

US$ 39.95

Price includes VAT for USA

Subscribe to journal

Immediate online access to all issues from 2019. Subscription will auto renew annually.

US$ 99

This is the net price. Taxes to be calculated in checkout.

Fig. 1
Fig. 2
Fig. 3
Fig. 4
Fig. 5
Fig. 6


  1. Abbaspourrad A, Carroll NJ, Kim SH, Weitz DA (2013a) Polymer microcapsules with programmable active release. J Am Chem Soc 135:7744–7750. doi:10.1021/ja401960f

  2. Abbaspourrad A, Datta SS, Weitz DA (2013b) Controlling release from pH-responsive microcapsules. Langmuir 29:12697–12702. doi:10.1021/la403064f

  3. Amstad E, Kim SH, Weitz DA (2012) Photo- and thermoresponsive polymersomes for triggered release. Angew Chem 51:12499–12503. doi:10.1002/anie.201206531

  4. Atkins P, de Paula J (2001) Physical chemistry, 7th edn. W. H. Freeman and Company, New York, p 178

  5. Bhagat AA, Jothimuthu P, Papautsky I (2007) Photodefinable polydimethylsiloxane (PDMS) for rapid lab-on-a-chip prototyping. Lab Chip 7:1192–1197. doi:10.1039/b704946c

  6. Brugarolas T, Park BJ, Lee MH, Lee D (2011) Generation of amphiphilic janus bubbles and their behavior at an air-water interface. Adv Func Mater 21:3924–3931. doi:10.1002/adfm.201100954

  7. Chen H, Zhao Y, Li J, Guo M, Wan J, Weitz DA, Stone HA (2011) Reactions in double emulsions by flow-controlled coalescence of encapsulated drops. Lab Chip 11:2312–2315. doi:10.1039/c1lc20265k

  8. Derjaguin BV, Churaev NV (1974) Structural component of disjoining pressure. J Colloid Interface Sci 49:249–255. doi:10.1016/0021-9797(74)90358-0

  9. DiLauro AM, Abbaspourrad A, Weitz DA, Phillips ST (2013) Stimuli-responsive core–shell microcapsules with tunable rates of release by using a depolymerizable poly(phthalaldehyde) membrane. Macromolecules 46:3309–3313. doi:10.1021/ma400456p

  10. Geiger S, Tokgoz S, Fructus A, Jager-Lezer N, Seiller M, Lacombe C, Grossiord JL (1998) Kinetics of swelling–breakdown of a W/O/W multiple emulsion: possible mechanisms for the lipophilic surfactant effect. J Controlled Release 52:99–107. doi:10.1016/s0168-3659(97)00202-2

  11. Guan X et al (2016) A dual-core double emulsion platform for osmolarity-controlled microreactor triggered by coalescence of encapsulated droplets. Biomicrofluidics 10:034111. doi:10.1063/1.4952572

  12. Jager-Lezer N et al (1997) Influence of lipophilic surfactant on the release kinetics of water-soluble molecules entrapped in a W/O/W multiple emulsion. J Controlled Release 45:1–13. doi:10.1016/s0168-3659(96)01507-6

  13. Jia Y, Ren Y, Liu W, Hou L, Tao Y, Hu Q, Jiang H (2016) Electrocoalescence of paired droplets encapsulated in double-emulsion drops. Lab Chip 16:4313–4318. doi:10.1039/c6lc01052k

  14. Jiang G, Thanoo BC, DeLuca PP (2002) Effect of osmotic pressure in the solvent extraction phase on BSA release profile from PLGA microspheres. Pharm Dev Technol 7:391–399. doi:10.1081/PDT-120015040

  15. Jiao J, Rhodes DG, Burgess DJ (2002) Multiple emulsion stability: pressure balance and interfacial film strength. J Colloid Interface Sci 250:444–450. doi:10.1006/jcis.2002.8365

  16. Kim JH, Jeon TY, Choi TM, Shim TS, Kim SH, Yang SM (2014a) Droplet microfluidics for producing functional microparticles. Langmuir 30:1473–1488. doi:10.1021/la403220p

  17. Kim SH, Park JG, Choi TM, Manoharan VN, Weitz DA (2014b) Osmotic-pressure-controlled concentration of colloidal particles in thin-shelled capsules. Nat Commun 5:3068. doi:10.1038/ncomms4068

  18. Lee SS, Abbaspourrad A, Kim SH (2014) Nonspherical double emulsions with multiple distinct cores enveloped by ultrathin shells. ACS Appl Mater Interfaces 6:1294–1300. doi:10.1021/am405283j

  19. Lee TY, Praveenkumar R, Oh Y-K, Lee K, Kim S-H (2016) Alginate microgels created by selective coalescence between core drops paired with an ultrathin shell. J Mater Chem B 4:3232–3238. doi:10.1039/c6tb00580b

  20. Lensen D et al (2011) Biodegradable polymeric microcapsules for selective ultrasound-triggered drug release. Soft Matter 7:5417. doi:10.1039/c1sm05324h

  21. Mezzenga R, Folmer BM, Hughes E (2004) Design of double emulsions by osmotic pressure tailoring. Langmuir 20:3574–3582. doi:10.1021/la036396k

  22. Niepa TH, Hou L, Jiang H, Goulian M, Koo H, Stebe KJ, Lee D (2016) Microbial nanoculture as an artificial microniche. Sci Rep 6:30578. doi:10.1038/srep30578

  23. Oh MJ, Ryu TK, Choi SW (2013) Hollow polydimethylsiloxane beads with a porous structure for cell encapsulation. Macromol Rapid Commun 34:1728–1733. doi:10.1002/marc.201300669

  24. Pistel KF, Kissel T (2000) Effects of salt addition on the microencapsulation of proteins using W/O/W double emulsion technique. J Microencapsul 17:467–483. doi:10.1080/026520400405723

  25. Simmons A, Padsalgikar AD, Ferris LM, Poole-Warren LA (2008) Biostability and biological performance of a PDMS-based polyurethane for controlled drug release. Biomaterials 29:2987–2995. doi:10.1016/j.biomaterials.2008.04.007

  26. Tao Y et al (2015) Rapid, targeted and culture-free viral infectivity assay in drop-based microfluidics. Lab Chip 15:3934–3940. doi:10.1039/c5lc00556f

  27. Tu F, Lee D (2012) Controlling the stability and size of double-emulsion-templated poly(lactic-co-glycolic) acid microcapsules. Langmuir 28:9944–9952. doi:10.1021/la301498f

  28. Windbergs M, Zhao Y, Heyman J, Weitz DA (2013) Biodegradable core–shell carriers for simultaneous encapsulation of synergistic actives. J Am Chem Soc 135:7933–7937. doi:10.1021/ja401422r

  29. Yeo SJ, Tu F, Kim SH, Yi GR, Yoo PJ, Lee D (2015) Angle- and strain-independent coloured free-standing films incorporating non-spherical colloidal photonic crystals. Soft Matter. doi:10.1039/c4sm02482f

Download references


This work is supported by the National Natural Science Foundation of China (Nos. 11672095 and 11372093) and Self-Planned Task (Nos. 201510B and 201606C) of State Key Laboratory of Robotics and System (HIT). The authors wish to acknowledge Dr. Xiaobin Li and Dr. Hongna Zhang (Harbin Institute of Technology) for help with the viscosity and interfacial tension test, and Prof. Lei Lei’s group (Harbin Medical University) for their assistance with the Micropipette Puller.

Author information

Correspondence to Yukun Ren or Hongyuan Jiang.

Additional information

This article is part of the topical collection “2016 International Conference of Microfluidics, Nanofluidics and Lab-on-a-Chip, Dalian, China” guest edited by Chun Yang, Carolyn Ren and Xiangchun Xuan.

Electronic supplementary material

Below is the link to the electronic supplementary material.

Supplementary material 1 (WMV 939 kb)

Supplementary material 2 (WMV 408 kb)

Supplementary material 1 (WMV 939 kb)

Supplementary material 2 (WMV 408 kb)

Rights and permissions

Reprints and Permissions

About this article

Verify currency and authenticity via CrossMark

Cite this article

Hou, L., Ren, Y., Jia, Y. et al. Osmolarity-controlled swelling behaviors of dual-cored double-emulsion drops. Microfluid Nanofluid 21, 60 (2017).

Download citation


  • Microfluidics
  • Double emulsion
  • Osmotic pressure
  • Coalescence
  • Rupture