Pharmaceutical Research

, Volume 30, Issue 12, pp 3059–3076 | Cite as

Toward the Establishment of Standardized In Vitro Tests for Lipid-Based Formulations, Part 3: Understanding Supersaturation Versus Precipitation Potential During the In Vitro Digestion of Type I, II, IIIA, IIIB and IV Lipid-Based Formulations

  • Hywel D. Williams
  • Philip Sassene
  • Karen Kleberg
  • Marilyn Calderone
  • Annabel Igonin
  • Eduardo Jule
  • Jan Vertommen
  • Ross Blundell
  • Hassan Benameur
  • Anette Müllertz
  • Colin W. Pouton
  • Christopher J. H. Porter
  • on behalf of the LFCS Consortium
Research Paper



Recent studies have shown that digestion of lipid-based formulations (LBFs) can stimulate both supersaturation and precipitation. The current study has evaluated the drug, formulation and dose-dependence of the supersaturation – precipitation balance for a range of LBFs.


Type I, II, IIIA/B LBFs containing medium-chain (MC) or long-chain (LC) lipids, and lipid-free Type IV LBF incorporating different doses of fenofibrate or tolfenamic acid were digested in vitro in a simulated intestinal medium. The degree of supersaturation was assessed through comparison of drug concentrations in aqueous digestion phases (APDIGEST) during LBF digestion and the equilibrium drug solubility in the same phases.


Increasing fenofibrate or tolfenamic acid drug loads (i.e., dose) had negligible effects on LC LBF performance during digestion, but promoted drug crystallization (confirmed by XRPD) from MC and Type IV LBF. Drug crystallization was only evident in instances when the calculated maximum supersaturation ratio (SRM) was >3. This threshold SRM value was remarkably consistent across all LBF and was also consistent with previous studies with danazol.


The maximum supersaturation ratio (SRM) provides an indication of the supersaturation ‘pressure’ exerted by formulation digestion and is strongly predictive of the likelihood of drug precipitation in vitro. This may also prove effective in discriminating the in vivo performance of LBFs.

Key words

bioavailability drug solubilization in vitro digestion testing in vitro models LFCS Consortium lipid-based drug delivery systems precipitation SEDDS solubility supersaturation 


Acknowledgments AND DISCLOSURES

This study results from a joint collaboration between members of the LFCS Consortium funded primarily by Capsugel and Sanofi R & D, with additional funding from Gattefossé, Merck Serono, NicOx, Roche, Bristol-Myers Squibb and Actelion. The authors would like to thank Dr. Laura Gordon and the Chemical Engineering department at Melbourne University for the XRPD analysis, and Rhiannon Smythe and Samuel Wood for determining the fenofibrate solubilities in the digested lipid formulations.

Supplementary material

11095_2013_1038_MOESM1_ESM.pdf (999 kb)
ESM 1 (PDF 998 KB)


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Copyright information

© Springer Science+Business Media New York 2013

Authors and Affiliations

  • Hywel D. Williams
    • 1
    • 7
  • Philip Sassene
    • 2
  • Karen Kleberg
    • 2
  • Marilyn Calderone
    • 3
  • Annabel Igonin
    • 4
  • Eduardo Jule
    • 5
  • Jan Vertommen
    • 4
  • Ross Blundell
    • 3
  • Hassan Benameur
    • 4
  • Anette Müllertz
    • 2
  • Colin W. Pouton
    • 6
  • Christopher J. H. Porter
    • 1
  • on behalf of the LFCS Consortium
  1. 1.Drug Delivery, Disposition and DynamicsMonash Institute of Pharmaceutical SciencesParkvilleAustralia
  2. 2.Department of Pharmaceutics, Faculty of Health and Medical SciencesUniversity of CopenhagenCopenhagenDenmark
  3. 3.Sanofi Research and DevelopmentMontpellierFrance
  4. 4.Capsugel R&DStrasbourgFrance
  5. 5.Capsugel Product Development CenterCambridgeUSA
  6. 6.Drug Discovery BiologyMonash Institute of Pharmaceutical SciencesParkvilleAustralia
  7. 7.Capsugel R&DStrasbourgFrance

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