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% Recovery factor

What is the formula for swab recovery factor?

thanks, very much

Hi,

It is necessary that first of all recovery studies be conducted on the different type of material you are going to take swabs from. You will then obtain a value between 50 and 100%. Depending on the specification you have, this may be acceptable or not.

Then, you will just have to divide the lab results (ug per swab) by that recovery factor to get an actual result.

Hope that helps

thomas

[quote=MMBACIU]What is the formula for swab recovery factor?

thanks, very much[/quote]

No formula. You perform a recovery test in duplicate. You place specific amount of your standard API (from worst case). By knowing the specigic amount you used when you perform your analysis theoreticaly you would expect to get exactly the same ammount but this is not the case.

Having performed a duplicate you get the mean of the two recovery factors you get. This Average you use in order to correct the values you get from your standard cleaning validation analysis. What I usually do in order not to correct the values I get, I do the correction using my recovery factor on the Acceptance Criteria and keep my up coming results from the analysis.

You should also set an Acceptance criterion for your Swab Recovery Factors,
say 70%.

For the solvent rinse usually I use the worst case recovery factor of 50% since it is due to interferences that I cannot calculate it correctly.

Hope this helps,

Best regards,

Thank you very much

% recovery factor = amount detected x 100/ amount spiked onto surface

best regards

[quote=MMBACIU]Thank you very much

% recovery factor = amount detected x 100/ amount spiked onto surface

best regards[/quote]

My friend I am sorry,
I thought it was too obvious.

Best regards,

[quote=Gigastorm]My friend I am sorry,
I thought it was too obvious.

Best regards,[/quote]

Yes indeed, you war very obvious, but I find this formula.
I undestending " recovery " means to say while swabbling the swab with I use may not be capable of removing the actual amount present on the surface of sampling area.
For identified this recovery factor, I need to now this %recovery, I must carried out that the same amount of solvent used for swabing the know concentration of spiked area with resembles my actual echipment part.
I detect concentration (x%)after swabbing out of know concentrationand then the value is 100-x% ?
I must undestending that, I am new in validation and english language is’n very good.
Thanks very much for undestending!

[quote=MMBACIU]Yes indeed, you war very obvious, but I find this formula.
I undestending " recovery " means to say while swabbling the swab with I use may not be capable of removing the actual amount present on the surface of sampling area.
For identified this recovery factor, I need to now this %recovery, I must carried out that the same amount of solvent used for swabing the know concentration of spiked area with resembles my actual echipment part.
I detect concentration (x%)after swabbing out of know concentrationand then the value is 100-x% ?
I must undestending that, I am new in validation and english language is’n very good.
Thanks very much for undestending![/quote]

That is exactly the concept, in deed.

Swab Recovery Factor
Do not forget in each case of your recovery study to perform in duplicate and get your mean recovery factor. Set criteria regarding the expected - accepted deviation between the two samples duplicate recovery factors that you will calculate. Moreover, set acceptance criterion for the mean recovery factor (say for instance Not Less than 70%).

Remember that for the Rinse Recovery Factor is a usual practice to use the worst case recovery factor of 50%.

Reason: Solvent rinse calculation includes probability for results below the limits of detection due to large analytical dilution factor .