Blending and Characterization of Pharmaceutical Powders

  • Carl A. AndersonEmail author
  • Natasha L. Velez
Part of the AAPS Advances in the Pharmaceutical Sciences Series book series (AAPS, volume 29)


Blending is a critical part of pharmaceutical manufacturing. It consists of two parts, the actual mixing of powdered ingredients to a desired degree of homogeneity and the analytical testing to confirm the same. Blending equipment and formulation considerations are discussed, along with potential mechanisms for a loss of quality of blends. A general description of the role of blending and its impact on the quality of finished dosage forms is presented. Traditional and on-line methods for assessing the quality of blends are described. Though widely accepted, traditional blend uniformity testing (thief sampling) has a number of potential weaknesses. On-line techniques such as near-infrared spectroscopy, Raman spectroscopy and light-induced fluorescence are considered as alternatives to traditional testing. The characteristics of the technology and potential challenges of analysis and implementation are discussed for these on-line methods.


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Copyright information

© American Association of Pharmaceutical Scientists 2018

Authors and Affiliations

  1. 1.Center for Pharmaceutical Technology, Duquesne UniversityPittsburghUSA

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