Inhalation homogeneous powders

Dry powders must be able to flow readily in order to leave the capsule or powder reservoir, but must also generate a fine aerosol enabling the patient to inhale a proper dose. These two requirements are often difficult to achieve simultaneously. Fine powders tend to be eohesive and have poor flow properties. Blending with a carrier phase, pelletization, and other approaches have been used to overcome these limitations. The featmes of blends and homogeneous powders are compared in Table 4 from a DPI device perspective ... 

Cadmium pigments are sold as homogeneous powders and as preparations mixed with barium sulfate to give the required tinting strength. To reduce the risk of inhalation (see Section 3.2.8), they are supplied as low-dust powders and fine granules. 

Clarity of solution -Homogeneity -pH of solution -Particle size -Flow characteristics (inhalation powders)... 

Kamer, S., Maier, M., Littringer, E. M., Urbanetz, N. A. (2014). Surface roughness effects on the tribo-charging and mixing homogeneity of adhesive mixtures used in dry powder inhalers. Powder Technology, 264,544—549. 

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