Moisture induced phase transformation in multi-component systems
Abstract
In this research, two well known water-solid interactions, deliquescence and crystal hydrate formation, were studied in multi-component systems. The main objective of this research was to investigate and understand the effect of various types of additives on the thermodynamics and/or kinetics of these moisture-induced phase transformations. Mixtures of deliquescent inorganic salts are known to be more susceptible to atmospheric moisture than the individual components, in other words mixtures tend to deliquesce at a lower critical relative humidity than the individual components. In this research, the phenomenon of deliquescence lowering has been illustrated in specific examples of deliquescent API and additive binary systems. Additional investigations were aimed at understanding possible ramifications on the physical and chemical stability of such systems. In the second part of research, an attempt was made to systematically investigate the potential underlying mechanisms responsible for the effect of hygroscopic and non-hygroscopic excipients on the transformation kinetics of hydrate formers. It has been shown that the effect of excipients on the kinetics of dehydration and hydration was found to be very complex and dependent of a multitude of factors that dictated the final effect of the excipients.
Degree
Ph.D.
Advisors
Taylor, Purdue University.
Subject Area
Pharmaceutical sciences|Organic chemistry
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