AAPS PharmSci

, Volume 5, Issue 1, pp 62–73 | Cite as

Rheology and stability of water-in-oil-in-water multiple emulsions containing Span 83 and Tween 80

Article

Abstract

Multiple emulsions are often stabilized using a combination of hydrophilic and hydrophobic surfactants. The ratio of these surfactants is important in achieving stable multiple emulsions. The objective of this study was to evaluate the long-term stability of water-in-oil-in-water (W/O/W) multiple emulsions with respect to the concentrations of Span 83 and Tween 80. In addition, the effect of surfactant and electrolyte concentration on emulsion bulk rheological properties was investigated. Light microscopy, creaming volume, and rheological properties were used to assess emulsion stability. It was observed that the optimal surfactant concentrations for W/O/W emulsion long-term stability were 20% wt/vol Span 83 in the oil phase and 0.1% wt/vol Tween 80 in the continuous phase. Higher concentrations of Tween 80 had a destructive effect on W/O/W emulsion stability, which correlated with the observation that interfacial film strength at the oil/water interface decreased as the Tween 80 concentration increased. High Span 83 concentrations increased the storage modulus G′ (solidlike) values and hence enhanced multiple emulsion stability. However, when 30% wt/vol Span 83 was incorporated, the viscosity of the primary W/O emulsion increased considerably and the emulsion droplets lost their shape. Salt added to the inner aqueous phase exerted an osmotic pressure that caused diffusion of water into the inner aqueous phase and increased W/O/W emulsion viscosity through an increase in the volume fraction of the primary W/O emulsion. This type of viscosity increase imposed a destabilizing effect because of the likelihood of rupture of the inner and multiple droplets.

Keywords

multiple emulsions stability rheology surfactant 

Preview

Unable to display preview. Download preview PDF.

Unable to display preview. Download preview PDF.

References

  1. 1.
    Matsumoto S, Kita Y, Yonezawa D. An attempt at preparing water-in-oil-in-water multiple phase emulsions. J Colloid Interface Sci. 1976;57:353–361.CrossRefGoogle Scholar
  2. 2.
    Opawale FO, Burgess DJ. Influence of interfacial rheological properties of mixed emulsifier films on the stability of water-in-oil-in-water emulsions. J Pharm Pharmacol. 1998;50:965–973.PubMedCrossRefGoogle Scholar
  3. 3.
    Florence AT, Whitehill D. Stability and stabilization of water-in-oil-in-water multiple emulsions. In: Shah DO, ed. Macro- and Microemulsions: Theory and Applications. ACS Symposium Series 272. Washington, DC: American Chemical Society, 1985:359–380.CrossRefGoogle Scholar
  4. 4.
    Shinoda K, Yoneyama T, Tsutsumi H. Evaluation of emulsifier blending. J Disper Sci Technol. 1980;1:1–12.CrossRefGoogle Scholar
  5. 5.
    Hou W, Papadopoulos KD. W1/O/W2 and O1/W/02 globules stabilized with Span 80 and Tween 80. Colloids Surf A: Physicochemical and Engineering Aspects. 1997;125:181–187.CrossRefGoogle Scholar
  6. 6.
    Chilamkurti RN, Rhodes CT. Transport across liquid membranes: effect of molecular structure. J Appl Biochem. 1990;2:17–24.Google Scholar
  7. 7.
    Davis SS. Physicochemical criteria for semi-solid dosage forms. In: Grimm W, ed. Stability Testing of Drug Products. Stuttgart, Germany: Wissenschaftliche Verlagesellschaft; 1987:40–56.Google Scholar
  8. 8.
    Sherman P. Rheological Properties of Emulsions. In: Becher P. ed. Encyclopedia of Emulsion Technology, Volume 1: Basic Theory. New York, NY: Marcel Dekker, 1983:215–248.Google Scholar
  9. 9.
    Princen HM. Rheology of foams and highly concentrated emulsions, II: experimental study of the yield stress and wall effects for concentrated oil-in-water emulsions. J Colloid Interface Sci. 1985;105:150–171.CrossRefGoogle Scholar
  10. 10.
    Pal R, Rhodes E. Emulsion flow in pipelines. Int J Multiphase Flow. 1989;15:1011–1017.CrossRefGoogle Scholar
  11. 11.
    Pal R. Rheological behavior of concentrated surfactant solutions and emulsions. Colloids Surf A: Physicochemical and Engineering Aspects. 1992;64:207–215.CrossRefGoogle Scholar
  12. 12.
    Pal R. Rheological behavior of surfactant-flocculated water-in-oil emulsions. Colloids Surf A: Physicochemical and Engineering Aspects. 1993;71:173–185.CrossRefGoogle Scholar
  13. 13.
    Terrisse I, Seiller M, Rabaron A, Grossiord JL, Magnet A, Le Hen-Ferrenbach C. Rheology: how to characterize and to predict the evolution of W/O/W multiple emulsions. Int J Cosmetic Sci. 1993;15:53–62.CrossRefGoogle Scholar
  14. 14.
    Mooney M. The viscosity of a concentrated suspension of spherical particles. J Colloid Sci. 1951;6:162–170.CrossRefGoogle Scholar
  15. 15.
    Kita Y, Matsumoto S, Yonezawa D. Viscometric method for estimating the stability of W/O/W type multiple-phase emulsions. J Colloid Interface Sci. 1977;62:87–94.CrossRefGoogle Scholar
  16. 16.
    Walstra P. Emulsion stability. In: Becher P, ed. Encyclopedia of Emulsion Technology. Vol 4. New York, NY: Marcel Dekker, 1996:1–56.Google Scholar
  17. 17.
    Jiao J, Rhodes DG, Burgess DJ. Multiple emulsion stability: pressure balance and interfacial film strength. J Colloid Interface Sci. 2002;250:444–450.PubMedCrossRefGoogle Scholar

Copyright information

© American Association of Pharmaceutical Scientists 2003

Authors and Affiliations

  1. 1.Pharmaceutical R&DPGRD, Pfizer IncGroton
  2. 2.School of PharmacyUniversity of ConnecticutStorrs

Personalised recommendations