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  • 1 Faculty of Pharmacy, University of Ljubljana, Aškerčeva 7, Ljubljana, Slovenia
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Abstract

This study presents a contribution in the development of a quick and accurate testing method for the determination of amorphous content using isothermal microcalorimetry. Examples demonstrated how the choice of the experimental conditions, especially sample load, temperature and humidity, influences the crystallization of the amorphous material. The suitability of this systematic approach was first tested on well-known lactose and afterwards on nifedipine as model compounds. It was shown that by proper method design and careful selection of experimental conditions, it is possible to achieve quick determination of the amorphous content in samples with a quantification limit of less than 1%, what is considerably better than by classical analytical methods such as DSC and XRPD. Our optimized microcalorimetry method gave also better results compared to previously reported literature data for nifedipine.

  • 1. Buckton, G, Choularton, A, Beezer, AE, Chatham, SM. The effect of the comminution technique on the surface-energy of a powder. Int J Pharm. 1988;47:121128. .

    • Crossref
    • Search Google Scholar
    • Export Citation
  • 2. Ahmed, H, Buckton, G, Rawlins, DA. The use of isothermal microcalorimetry in the study of small degrees of amorphous content of a hydrophobic powder. Int J Pharm. 1996;130:195201. .

    • Crossref
    • Search Google Scholar
    • Export Citation
  • 3. Phipps, MA, Mackin, LA. Application of isothermal microcalorimetry in solid state drug development. Pharm Sci Technol Today. 2000;3:917. .

    • Crossref
    • Search Google Scholar
    • Export Citation
  • 4. Buckton, G, Darcy, P. Assessment of disorder in crystalline powders—a review of analytical techniques and their application. Int J Pharm. 1999;179:141158. .

    • Crossref
    • Search Google Scholar
    • Export Citation
  • 5. Gaisford, S, Buckton, G. Potential application of microcalorimetry for the study of physical processes in pharmaceuticals. Thermochim Acta. 2001;380:185198. .

    • Crossref
    • Search Google Scholar
    • Export Citation
  • 6. Sousa e Silva, JP, Sousa Lobo, JM. Compatibility studies between nebicapone, a novel COMT inhibitor, and excipients using stepwise isothermal high sensitivity DSC method. J Therm Anal Calorim. 2010;102:317321. .

    • Crossref
    • Search Google Scholar
    • Export Citation
  • 7. Wang, J, Cheng, D, Zeng, N, Xia, H, Fu, Y, Yan, D, Zhao, Y, Xiao, X. Application of microcalorimetry and principal component analysis. J Therm Anal Calorim. 2010;102:137142. .

    • Crossref
    • Search Google Scholar
    • Export Citation
  • 8. Wadso, I. Characterization of microbial activity in soil by use of isothermal microcalorimetry. J Therm Anal Calorim. 2009;95:843850. .

  • 9. Roskar, R, Vivoda, M, Kmetec, V. Use of isothermal microcalorimetry for prediction of oxidative stability of several amino acids. J Therm Anal Calorim. 2008;92:791794. .

    • Crossref
    • Search Google Scholar
    • Export Citation
  • 10. Hancock, BC, Zografi, G. Characteristics and significance of the amorphous state in pharmaceutical systems. J Pharm Sci. 1997;86:112. .

  • 11. Vippagunta, SR, Maul, KA, Tallavajhala, S, Grant, DJW. Solid-state characterization of nifedipine solid dispersions. Int J Pharm. 2002;236:111123. .

    • Crossref
    • Search Google Scholar
    • Export Citation
  • 12. Apperley, DC, Forster, AH, Fournier, R, Harris, RK, Hodgkinson, P, Lancaster, RW, Rades, T. Characterisation of indomethacin and nifedipine using variable-temperature solid-state NMR. Magn Reson Chem. 2005;43:881892. .

    • Crossref
    • Search Google Scholar
    • Export Citation
  • 13. Zajc, N, Obreza, A, Bele, M, Srčič, S. Physical properties and dissolution behavior of nifedipine/mannitol solid dispersions prepared by hot melt method. Int J Pharm. 2005;291:5158. .

    • Crossref
    • Search Google Scholar
    • Export Citation
  • 14. Angberg, M. Lactose and thermal-analysis with special emphasis on microcalorimetry. Thermochim Acta. 1995;248:161176. .

  • 15. Giron, D, Monnier, S, Mutz, M, Piechon, P, Buser, T, Stowasser, F, Schulze, K, Bellus, M. Comparison of quantitative methods for analysis of polyphasic pharmaceuticals. J Therm Anal Calorim. 2007;89:729743. .

    • Crossref
    • Search Google Scholar
    • Export Citation
  • 16. Briggner, LE, Buckton, G, Bystrom, K, Darcy, P. The use of isothermal microcalorimetry in the study of changes in crystallinity induced during the processing of powders. Int J Pharm. 1994;105:125135. .

    • Crossref
    • Search Google Scholar
    • Export Citation
  • 17. Sebhatu, T, Angberg, M, Ahlneck, C. Assessment of the degree of disorder in crystalline solids by isothermal microcalorimetry. Int J Pharm. 1994;104:135144. .

    • Crossref
    • Search Google Scholar
    • Export Citation
  • 18. Ahlneck, C, Zografi, G. The molecular-basis of moisture effects on the physical and chemical-stability of drugs in the solid-state. Int J Pharm. 1990;62:8795. .

    • Crossref
    • Search Google Scholar
    • Export Citation
  • 19. Giron, D, Remy, P, Thomas, S, Vilette, E. Quantitation of amorphicity by microcalorimetry. J Thermal Anal. 1997;48:465472. .

  • 20. Oksanen, CA, Zografi, G. The relationship between the glass-transition temperature and water-vapor absorption by poly(vinylpyrrolidone). Pharm Res. 1990;7:654657. .

    • Crossref
    • Search Google Scholar
    • Export Citation
  • 21. Callahan, JC, Cleary, GW, Elefant, M, Kaplan, G, Kesler, T, Nash, RA. Equilibrium moisture-content of pharmaceutical excipients. Drug Dev Ind Pharm. 1982;8:355369. .

    • Crossref
    • Search Google Scholar
    • Export Citation
  • 22. Aso, Y, Yoshioka, S, Kojima, S. Feasibility of using isothermal microcalorimetry to evaluate the physical stability of amorphous nifedipine and phenobarbital. Thermochim Acta. 2001;380:199204. .

    • Crossref
    • Search Google Scholar
    • Export Citation

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