pH-Induced Precipitation Behavior of Weakly Basic Compounds: Determination of Extent and Duration of Supersaturation Using Potentiometric Titration and Correlation to Solid State Properties

  title={pH-Induced Precipitation Behavior of Weakly Basic Compounds: Determination of Extent and Duration of Supersaturation Using Potentiometric Titration and Correlation to Solid State Properties},
  author={Yi Ling Hsieh and Grace A. Ilevbare and Bernard van Eerdenbrugh and Karl J. Box and Manuel Vicente S{\'a}nchez-F{\'e}lix and Lynne S. Taylor},
  journal={Pharmaceutical Research},
ABSTRACTPurposeTo examine the precipitation and supersaturation behavior of ten weak bases in terms of the relationship between pH-concentration-time profiles and the solid state properties of the precipitated material.MethodsInitially the compound was dissolved at low pH, followed by titration with base to induce precipitation. Upon precipitation, small aliquots of acid or base were added to induce slight subsaturation and supersaturation respectively and the resultant pH gradient was… 

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