V3I10P21

Pharmaceutical Powders: Properties, Evaluation, Manufacturing and Quality Control: Principles, Techniques and Applications

CH. Vidyulatha^1*, N Nikhil²

Abstract

Pharmaceutical powders are solid dosage forms made of finely divided particles of one or more active ingredients, with or without excipients. They are used directly as medicines and also serve as the starting material for tablets, capsules, granules, solutions and suspensions. The quality of a powder depends largely on its physical and mechanical properties: particle size and size distribution, shape, density, porosity, moisture content, cohesiveness and flowability. These properties govern mixing, segregation, filling accuracy, stability and the uniformity of dose between batches. This article reviews the classification of pharmaceutical powders, their key properties, size reduction, mixing and segregation, and the common methods of evaluation, including particle-size analysis, bulk and tapped density, angle of repose, Carr’s index and Hausner ratio. It then describes the preparation, packaging, storage and quality control of powders and their main applications. Oral Rehydration Salts (ORS) are used as a case study to show how these principles are applied in practice. The review concludes that no single test describes a powder adequately; a combination of controlled processing, suitable evaluation, protective packaging and systematic quality control is needed to deliver a safe and consistent product.

Keywords:

pharmaceutical powders, particle size, flowability, segregation, Carr’s index, Hausner ratio, quality control, oral rehydration salts