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AAPS PharmSciTech. 2006 September; 7(3): E70–E73.
Published online 2006 August 4. doi:  10.1208/pt070365
PMCID: PMC2750507

Estimation of intramolecular cyclization activation energies via isothermal gravimetric analysis: A technical note

Summary and Conclusion

Isothermal gravimetric analysis was used to monitor the weight loss of 4 exploratory compounds as an indicator of their solid-state thermal stability. Data obtained from TGA were further processed via a model-free isoconversional method to estimate the activation energy values. These values ranged from 140 to 218 kJ/mol and were inversely related to their corresponding surface areas. Based on their activation energy values, the relative stability of these 4 exploratory compounds can be ranked as C>D>B>A and their formulation development activities can be prioritized.

Keywords: isothermal analysis, thermogravimetric analysis, isoconversional model, intramolecular cyclization, model-free kinetics

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Selected References

These references are in PubMed. This may not be the complete list of references from this article.
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