Just wondering if anyone can give me some kind of direction in handling unknown peaks detected during testing of cleaning validation samples (swabs), i am looking at alterante methods like TOC to address unknown peaks.
Thanks:)
Just wondering if anyone can give me some kind of direction in handling unknown peaks detected during testing of cleaning validation samples (swabs), i am looking at alterante methods like TOC to address unknown peaks.
Thanks:)
just a correction i am not looking at TOC as an alternate method.
Dear Mr. cs2009,
This is a frequently asked question by many who are involved in cleaning validation activities. The answer might not be as simple as the question itself. This is an issue which is related to how analytical methods are developed and should be dealt with before the execution of CV (i.e. before actual swab or rinse sampling starts). I try to highlight some of the factors which could cause unknown peaks to appear in the HPLC chromatograms when testing CV samples.
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Hope the reply will be helpful.
Thanks
We are a big manufacture, more than 100 products produced. It is very hard to do investigation for unknown peak. We often has some unknown peaks not matching with detergent, placebo, surface or swab blank and provius 3 to 7 products active. What is the requirment to investigate unknown for CV from reguletory point of view? At what level we should do investigation?
Dear Mr. b0b,
I can suggest you three things:
A. Make the HPLC method as specific as possible (although I am not in the favor of developing/using too specific HPLC methods). If you consider your HPLC method to be specific enough (i.e. nothing else can be done to make it more residue specific) then in that case simply estimate the amount of target residue and neglect other peaks, as you are interested in estimating the amount of worst-case residue not any other residue (this case is applicable only when the relative peak areas are small, see point no. C).
B. Second approach is to use more universal (non-specific) methods for residue analysis such as TOC (provided the residues are organic in nature), NIR etc.
C. Even if you want to go ahead with current HPLC method and are interested in knowing/understanding more about unknown peaks then you have to consider the unknown peaks as impurities and try to limit them in formulations as per the ICH Q3 guidelines (i.e. consider reporting threshold, identification threshold and qualification threshold for describing unknown residues). If the amount of residue(s) detected = identification/qualification threshold limit, then you have to identify/qualify the residue. In order to do that you may have to use advanced analytical techniques such as LC-MS, NMR etc. for identification/qualification of residues.
Regards,
Ovais