FAQ - Contador de partículas de líquidos

APSS 200 Parenteral Particle Counter

Pregunta
If we set the data as counts per ml (normalized count), then the will the reading be interpreted as counts/ml directly? or what is the difference between raw count and normalized count?

Respuesta

Regarding an APSS-200 system with a LiQuilaz E20P sensor (2 -125 um)

The data you view is based upon one criterion: do you manufacture Large or Small Volume Injectables (the definition would follow either USP, EP or JP standards)?

Small Volume (SVI) settings need to be: Accumulative, Normalized to Counts per Container.

This is, you need to see particles of size X and larger and this will encompass all particles of that size, and the legislation allows for a certain maximum particles in a single dose, and in SVIs this is deemed to be a unit volume of a container. Now USP/EP will require several (>10) of these containers to be pooled and the SamplerSight software allows for this in the configuration. The difference between Normalized and Raw is that normalized will allow for minor tolerance in a fixed volume, so you could take a 5 mL sample and the results will be essentially an average of the total counts / total volume = counts per unit volume. This is critical for compliance. Raw counts are the actual particles in suspension that are seen during a sample run.

Example:

Sample = 5mL, total counts = 125

Raw counts = 125

Counts / mL = 25

Large Volume (LVI) settings need to be: Accumulative, normalized to counts per mL.

Again, all particles of size x and greater and now due to the volume of dosage the criteria is based upon /mL as it is unknown how much final solution will be delivered.

The environment for both USP and EP needs to be in a laminar flow cabinet, EP define and ISO5 limit. SamplerSight has a calibration wizard included and this again should be followed with the instrument in a laminar flow cabinet.

For more information on understanding results from liquid particle counters I suggest you purchase the book Understanding Liquid Particle Counters.