The particle Size Dry method is widely used in the Pharma industry to determine the Particle Size distribution (PSD) of a substance. PSD Wet method is also another alternate technique. The Particle Size Distribution is one of the key physical properties of the substance and is a key technique in the Pharmaceutical field.

The PSD instrument (Particle Size Analyzer) is used to determine the Particle distribution of material. Since the Dry PSD technique is widely used, a suitable Particle Size Dry method shall be developed. To cater to the Pharma professional and Pharma Industry requirements, an Analytical Method Development procedure is provided as guidance.

Particle Size (PSD) Wet Dry Method, PSD Method Validation

Particle Size Wet Method Latest Guidance

Particle Size Dry Method Latest Guidance
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Particle Size Dry Method Development procedure

A detailed discussion of considerations for the Particle Size Dry Method (PSD Dry Method) has given below.

If there is no insoluble medium for the sample go for dry powder analysis.

For dry powder analysis, the sample shall have free-flowing or crystalline in nature.

Take about 2 grams of the sample and place it in the sample tray. Initially set the jet air pressure at 2.0 bar and the feed rate at 50 %. Optimize the feed rate and pressure.

Set the gates in such a way that to get the obscuration 0. 5 % to 3% for fine particles and course materials about 7 % or as per the system manual.

If the sample has agglomeration or a bad peak shape increase jet pressure and feed rate simultaneously to remove the agglomeration and get a good peak shape.

Minimize the jet pressure or feed rate or both if particles are breaking.

Fine-tune the jet pressure and feed rate to get reproducible results.

The Developed Method finalization is after the successful completion of the Reproducibility and batch analysis. In the dry powder method, there is no repeatability.

In reproducibility pour about 2 grams of the sample into the sample tray six times and analyze each once.

If results are within acceptance criteria then this tentative method can be used for regular analysis.

The confirmation of the tentative method will depend on the Method validation outcome.

Read, never before article on “Particle Size Analysis of Wet Method” HERE.

Key Notes for Particle Size Dry Method Development

Use the dry powder method for materials consisting of more than 5 microns

In the dry powder method, particles shall not be fragile nature and fine needles in nature.

Examine the Particle size and shape by using Microscope. The method selection can take after verification of the “nature of the particle”.

Perform the method development activity for sifted, milled, and micronized type materials.

Read never-before articles – PSD Method Validation Procedure Made Easy