# Calculation of recovery factor

I want to know that what is recoery, what is recovery factor, how recovery is determined.What should be the limits for recovery?

the importence of recovery .

hi guys,
as far as i am concerned it is as follows :
when we do cleaning and take the sample for analysis either by swab or rinse method the chances of previous product that can be removed by the swab is not sure. So for that purpose the known amount of drug is spread on a plate that is the material for which we are going to come in routine practice and that will be tested for how much amount of drug is being removed from the surface of the test material if done as per routine method of sampling say swab or rinse.
this swab or rinse sample will be tested to know how much amount of drug is present in that sample. then basing on that the remaining left out quantity will be used for further calculations and the qty. removable i.e detected is called as recovery factor. in general it is assumed that if the recovery factor is more than 50% its satisfactory to use that method.
for ex. say 100mg of drug is spreaded on the test material of certain known area (say SS316 or Acrylic sheet - recovery may vary basing on the nature of the material) and swabbing is done or rinsing is done and you analyse the sample then the found value is 75mg then the recovery factor is 75% So 25% is still left on the material and this value will be included in calculation of your residue of previous product.
would like to hear form others too on this.
cheers
astute

[quote=ankur.sharma_13@yahoo.con][quote=yogesh_mutkule]I want to know that what is recoery, what is recovery factor, how recovery is determined.What should be the limits for recovery,

the importence of recovery .[/quote]

Sharma, spike known amount of drug ,allow it to dry ,swab it with extracting solvent and analyse the solution.Calculate the % of recovery using known standard solution.

``      Recovery factor is a response factor specific to method and swab plate .We have  a limit of 80% recovery for cleaning validation.``

hello,
i need calculation of recovery factor for rinsing and swab samples
i have one doubt the rf for each solution of disorbant will differ or not
plz send me clear data
regarreds
pawan

I believe some other considerations need to be mentioned. Spiking a sample material with a known amount of active will not (always) result in a representive situation for the residuals normally left after a cleaning proces. To my believe it is much easier to wipe of a relatively high concentration of material than the last spores of residuals normally left.

How can this method then be consideres to give acurate results. And taking this in acount, how can the whole subject of cleaning validation be considered quantitatvely?

If values produced by cleaning validation are so uncertain, why are we trying to determine swaps with so high accuracy. Also take in consideration the safety limits put on cleaning validation requirements which are factors 1000 or more.

Rob

HI,

Recovery factor means any one addict to the drugs to recover the ordinary man its called recovery factor,and easy to recover the drug addict man.

Thank you…

Hi All,

Recovery factor is the lowest amount of Active that can remove from the stainless steel plat during cleaning validation study. so during cleaning validation study when you do Precision, Recovery, Intermediate precision, … the lowest percent obtains from these tests is called recovery factor.