Particulate Matter Count - Filter Paper Analysis

Two standard USP procedures are used to assess particulate matter count:

• Method 1: Light Obscuration Particle Count Test
• Method 2: Microscopic Particle Count Test

For Method 2, the process involves drawing the sample through a membrane using a filter assembly, followed by microscopic evaluation. The membrane captures particles, which are then counted and classified based on their size and shape. This gives a direct, visual record of the sample’s particulate profile.

Filter paper analysis supports quality assurance across parenteral products. By capturing particles on a membrane and inspecting them under magnification, teams can validate whether the formulation aligns with regulatory expectations. The method works across transparent, opaque, or complex formulations and is commonly used during both development and batch release.

Running a consistent particulate matter count helps flag issues before they reach later production stages. Whether the concern is raw material variability, container compatibility, or process-related contamination, early detection enables faster and more effective course correction.

It also helps manufacturers meet the requirements of USP chapters 788, 789, 790, and 1788.2, reducing the risk of deviation reports or batch failures.

• filtration, the retained matter is examined microscopically to identify and count particles. The results are then benchmarked against pharmacopeial limits.
• ImageProVision offers two software tools to support this analysis:.
• ipvPCount for semi-automatic measurement.
• ipvAutoCount for fully automated workflows.
• Both tools are designed to support compliance reporting and documentation in accordance with standard USP protocols.