Skip to main content
Log in

Analysis of Dissolution Data Using Modified Versions of Noyes–Whitney Equation and the Weibull Function

  • Research Paper
  • Published:
Pharmaceutical Research Aims and scope Submit manuscript

Purpose

The aim of the study is to develop modified, branched versions of the Noyes–Whitney and the Weibull equations, including explicitly the solubility/dose parameter, for the analysis of dissolution data, which reach the plateau either at infinite or finite time.

Methods

The modified Weibull function is applied to the analysis of experimental and literature dissolution data. To demonstrate the usefulness of the mathematical models, two model drugs are used: one highly soluble, metoprolol, and one relatively insoluble, ibuprofen.

Results

The models were fitted successfully to the data performing better compared with their classic versions. The advantages of the use of the models presented are several. They fit better to a large range of datasets, especially for fast dissolution curves that reach complete dissolution at a finite time. Also, the modified Weibull presented can be derived from differential equations, and it has a physical meaning as opposed to the purely empirical character of the original Weibull equation. The exponent of the Weibull equation can be attributed to the heterogeneity of the process and can be explained by fractal kinetics concepts. Also, the solubility/dose ratio is present explicitly as a parameter and allows to obtain estimates of the solubility even when the dissolution data do not reach the solubility level.

Conclusion

The use of the developed branched equations gives better fittings and specific physical meaning to the dissolution parameters. Also, the findings underline the fact that even in the simplest, first-order case, the speed of the dissolution process depends on the dose, a fact of great importance in biopharmaceutic classification for regulatory purposes.

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

Access this article

Price excludes VAT (USA)
Tax calculation will be finalised during checkout.

Instant access to the full article PDF.

Fig. 1
Fig. 2
Fig. 3
Fig. 4

Similar content being viewed by others

References

  1. A. S. Noyes W. R. Whitney (1897) ArticleTitleThe rate of solution of solid substances in their own solutions J. Am. Chem. Soc. 19 930–934

    Google Scholar 

  2. P. Costa J. M. Sousa Lobo (2001) ArticleTitleModeling and comparison of dissolution profiles Eur. J. Pharm. Sci. 13 123–133 Occurrence Handle1:CAS:528:DC%2BD3MXisF2qs78%3D Occurrence Handle11297896

    CAS  PubMed  Google Scholar 

  3. W. Weibull (1951) ArticleTitleA statistical distribution of wide applicability J. Appl. Mech. 18 293–297

    Google Scholar 

  4. F. Langenbucher (1972) ArticleTitleLinearization of dissolution rate curves by the Weibull distribution J. Pharm. Pharmacol. 24 979–981 Occurrence Handle1:CAS:528:DyaE3sXmt1Wgsg%3D%3D Occurrence Handle4146531

    CAS  PubMed  Google Scholar 

  5. J. A. Goldsmith N. Randall S. D. Ross (1978) ArticleTitleOn methods of expressing dissolution rate data J. Pharm. Pharmacol. 30 347–349 Occurrence Handle1:STN:280:CSeC1MnksF0%3D Occurrence Handle26763

    CAS  PubMed  Google Scholar 

  6. P. Romero J. B. Costa X. Castel-Maroteaux D. Chulia (1991) Statistical optimization of a controlled release formulation obtained by a double compression process: application of a Hadamard matrix and a factorial design J. I. Wells M. H. Rubinstein (Eds) Pharmaceutical Technology, Controlled Drug Release, Vol. 2 Ellis Harwood New York 44–58

    Google Scholar 

  7. G. K. Vudathala J. A. Rogers (1992) ArticleTitleDissolution of fludrocortisone from phospholipid coprecipitates J. Pharm. Sci. 82 282–286

    Google Scholar 

  8. P. V. Pedersen J. W. Myrick (1978) ArticleTitleVersatile kinetic approach to analysis of dissolution data J. Pharm. Sci. 67 1450–1455 Occurrence Handle1:CAS:528:DyaE1cXmtVCis7c%3D Occurrence Handle702301

    CAS  PubMed  Google Scholar 

  9. F. N. Christensen F. Y. Hansen H. Bechgaard (1980) ArticleTitlePhysical interpretation of parameters in the Rosin–Rammler–Sperling–Weibull distribution for drug release from controlled release dosage forms J. Pharm. Pharmacol. 32 580–582 Occurrence Handle1:CAS:528:DyaL3cXmt1Gmuro%3D Occurrence Handle6106699

    CAS  PubMed  Google Scholar 

  10. E. Rinaki A. Dokoumetzidis P. Macheras (2003) ArticleTitleThe mean dissolution time depends on dose/solubility ratio Pharm. Res. 20 406–408 Occurrence Handle1:CAS:528:DC%2BD3sXhslGrtr4%3D Occurrence Handle12669960

    CAS  PubMed  Google Scholar 

  11. P. Lansky M. Weiss (1999) ArticleTitleDoes the dose-solubility ratio affect the mean dissolution time of drugs? Pharm. Res. 16 1470–1476 Occurrence Handle1:CAS:528:DyaK1MXmtVKkurs%3D Occurrence Handle10496667

    CAS  PubMed  Google Scholar 

  12. P. Lansky M. Weiss (2003) ArticleTitleClassification of dissolution profiles in terms of fractional dissolution rate and a novel measure of heterogeneity J. Pharm. Sci. 92 1632–1647 Occurrence Handle1:CAS:528:DC%2BD3sXmtFektro%3D Occurrence Handle12884250

    CAS  PubMed  Google Scholar 

  13. P. Macheras A. Dokoumetzidis (2000) ArticleTitleOn the heterogeneity of drug dissolution and release Pharm. Res. 17 108–112 Occurrence Handle10.1023/A:1007596709657 Occurrence Handle1:CAS:528:DC%2BD3cXitVOqtb8%3D Occurrence Handle10751023

    Article  CAS  PubMed  Google Scholar 

  14. R. Kopelman (1988) ArticleTitleFractal reaction kinetics Science 241 1620–1626 Occurrence Handle1:CAS:528:DyaL1cXlvFyitr0%3D

    CAS  Google Scholar 

  15. P. Lansky V. Lanska M. Weiss (2004) ArticleTitleA stochastic differential equation model for drug dissolution and its parameters J. Control. Release 100 267–274 Occurrence Handle10.1016/j.jconrel.2004.08.021 Occurrence Handle1:CAS:528:DC%2BD2cXps1Oqsr8%3D Occurrence Handle15544874

    Article  CAS  PubMed  Google Scholar 

  16. J. E. Polli G. S. Rekhi L. L. Augsburger V. P. Shah (1997) ArticleTitleMethods to compare dissolution profiles and a rationale for wide dissolution specification for metoprolol tablets J. Pharm. Sci. 86 690–700 Occurrence Handle10.1021/js960473x Occurrence Handle1:CAS:528:DyaK2sXjtV2qtb8%3D Occurrence Handle9188051

    Article  CAS  PubMed  Google Scholar 

  17. Official monographs. Ibuprofen, USP XXIV, NF 19, 854–858 (2000).

  18. E. Rinaki G. Valsami P. Macheras (2003) ArticleTitleQuantitative biopharmaceutics classification system: the central role of dose/solubility ratio Pharm. Res. 20 1917–1925 Occurrence Handle1:CAS:528:DC%2BD3sXpvVShsLg%3D Occurrence Handle14725354

    CAS  PubMed  Google Scholar 

  19. E. Rinaki A. Dokoumetzidis G. Valsami P. Macheras (2004) ArticleTitleIdentification of biowaivers among Class II drugs: theoretical justification and practical examples Pharm. Res. 21 1567–1572 Occurrence Handle10.1023/B:PHAM.0000041450.25106.c8 Occurrence Handle1:CAS:528:DC%2BD2cXnsFyjsLs%3D Occurrence Handle15497681

    Article  CAS  PubMed  Google Scholar 

Download references

Author information

Authors and Affiliations

Authors

Corresponding author

Correspondence to Panos Macheras.

Rights and permissions

Reprints and permissions

About this article

Cite this article

Dokoumetzidis, A., Papadopoulou, V. & Macheras, P. Analysis of Dissolution Data Using Modified Versions of Noyes–Whitney Equation and the Weibull Function. Pharm Res 23, 256–261 (2006). https://doi.org/10.1007/s11095-006-9093-3

Download citation

  • Received:

  • Accepted:

  • Published:

  • Issue Date:

  • DOI: https://doi.org/10.1007/s11095-006-9093-3

Key Words

Navigation