Pharmaceutical Research

, Volume 11, Issue 10, pp 1385–1390

Formulation and Intestinal Absorption Enhancement Evaluation of Water-in-Oil Microemulsions Incorporating Medium-Chain Glycerides

  • Panayiotis P. Constantinides
  • Jean-Paul Scalart
  • Cindy Lancaster
  • Joseph Marcello
  • Gary Marks
  • Harma Ellens
  • Philip L. Smith


We developed self-emulsifying water-in-oil (w/o) microemulsions incorporating medium-chain glycerides and measured their conductance, viscosity, refractive index and particle size. Formulation of Calcein (a water-soluble marker molecule, MW = 623), or SK&F 106760 (a water-soluble RGD peptide, MW = 634) in a w/o microemulsion having a composition of Captex 355/Capmul MCM/Tween 80/Aqueous (65/22/10/3, % w/w), resulted in significant bioavailabil-ity enhancement in rats relative to their aqueous formulations. Upon intraduodenal administration the bioavailability was enhanced from 2% for Calcein in isotonic Tris, pH 7.4 to 45% in the microemulsion and from 0.5% for SK&F 106760 in physiological saline to 27% in the microemulsion formulation. The microemulsion did not induce gross changes in GI mucosa at a dosing volume of 3.3 ml/kg. These results suggest that water-in-oil microemulsion systems may be utilized for enhancement of intestinal drug absorption.

water-in-oil microemulsions medium-chain glycerides enhancer intestinal absorption fibrinogen receptor antagonist 


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Copyright information

© Plenum Publishing Corporation 1994

Authors and Affiliations

  • Panayiotis P. Constantinides
    • 1
  • Jean-Paul Scalart
    • 2
  • Cindy Lancaster
    • 1
  • Joseph Marcello
    • 1
  • Gary Marks
    • 1
  • Harma Ellens
    • 1
  • Philip L. Smith
    • 1
  1. 1.Department of Drug Delivery, Pharmaceutical TechnologiesSmithKline Beecham PharmaceuticalsKing of PrussiaPennsylvania
  2. 2.School of PharmacyUniversity of RennesFrance
  3. 3.Drug Delivery DepartmentSmithKline Beecham PharmaceuticalsKing of PrussiaPennsylvania

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