cleaning validation

How to select the swab medium?

Hoe to fix the limits for rinse sample?

[quote=balamurugan]How to select the swab medium?

Hoe to fix the limits for rinse sample?[/quote]

the medium you need should be a solvent that the active ingredient (worst case) soluble in . thus any resibues will be detected easily

Dear Balamurugan,

the criteria to select a solvent for swabbing are mainly the solubility of the targeted substance (usually an active ingredient, but also degradation products, detergents, etc.), but points to consider are also toxicity, volatility and interference with the analytical method. If you use HPLC for the sample analysis, the components of the mobile phase are a good starting point.

Regarding the limits for rinse sampling, usually they are the same as for swab sampling, only that the absolute quantity of target substance found in the swab sample is what you find on the swabbed portion (normally 100 cm²) and for the rinse sample it is what you find on the rinsed portion (which could be the entire equipment surface). Per unit of surface it should be the same amount. Remember that you need to define and validate the quantity of rinsing solvent and keep it constant throughout the entire validation (recovery test and cleaning test). For the amount of rinse solvent a range of 0,2 - 0,5 ml/cm² and up to 1 ml/cm² is a good starting point.

Best regards