Isoconversión Isotermal para una estimación rápida de la vida útil de comprimidos de Ácido acetil salicílico

Abstract

Long-term stability studies of pharmaceutical forms require a large amount of resources and time for their development.
Alternatively, more efficient methods have been proposed, among these, the paradigm of isothermal isoconversion
is highlighted to estimate the useful life in a few weeks. This approach recognizes pharmaceutical forms
as heterogeneous systems without a single kinetic order, it establishes a maximum percentage of degradation and
assumes the same kinetics for all degradation processes independently of the conditions in which they are carried
out, and it also includes in the calculations the effect of humidity through a modification to the Arrhenius equation.
The objective of the present investigation was to apply the isothermal isoconversion in order to estimate the shelf-life
of the acetylsalicylic acid tablets in few weeks. Six combinations of humidity and temperature were used to establish
the necessary time for the formation of 0.15% salicylic acid, being calculate activation energy too, the Monte
Carlo method was applied with 5000 simulations considering values of temperature and relative humidity within a
certain range. The estimated shelf-life life for raw material was 415.5 days and 35.6 days for tablets. This method
demonstrates in a short time the impact of the excipients and the manufacturing process on the stability of a drug.