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Re: Use of volumetric solutions
Posted: Mon Jul 30, 2012 8:29 am
by Peter Apps
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This is the critical bit:
"5. Your firm has failed to maintain complete records of all testing and standardization of laboratory reference standards and standard
solutions [21 CFR 211.194(c)].
A laboratory reference standard is one that has been made up in the testing laboratory - the finding simply asks the lab to check its own work. A certified reference material has been prepared and certified (with uncertainty and traceability) in a laboratory which is certified and/or accredited by a national body, which is itself part of a huge international network in which everyone checks everyone else and agrees on the basis of audited performance that results (e.g. the certified concentration of a certified reference material) can be accepted as "correct". So for a routine QC lab for example, it makes sense to check standards prepared in house, it does not make sense to check certified reference materials - for reasons that have already been discussed earlier in the thread.
Peter
Re: Use of volumetric solutions
Posted: Mon Jul 30, 2012 2:38 pm
by KM-USA
Peter - very interesting. Is there official documentation that confirms this thinking, or a direct definition?
Re: Use of volumetric solutions
Posted: Mon Jul 30, 2012 2:59 pm
by Peter Apps
At the top end of the traceability and certification chain are the national metrology labs or institutes, guessing from your name that you are in the USA for you it would be NIST, and the BIPM in Paris. Have a look at
http://www.bipm.org/en/convention/wmd/2 ... ility.html and elsewhere on the BIPM site to get you started.
Most countries that care about international trade have certification or accreditation bodies that monitor and approve the competence of analytical labs. These enable trading partners to trust each other's results for e.g. pesticide residues in foods. Labs that produce certified reference materials will be accredited by their national accreditation service, and they will have explicit traceability chains to the metrological standards.
Googling "laboratory accreditation" will get you lots to read.
Peter
Re: Use of volumetric solutions
Posted: Tue Jul 31, 2012 12:35 pm
by krickos
Hi
KM this is from ICH Q7a as an example:
11.17 Primary reference standards should be obtained as appropriate for the manufacture of APIs. The source of each primary reference standard should be documented. Records should be maintained of each primary reference standard’s storage and use in accordance with the supplier’s recommendations. Primary reference standards obtained from an officially recognised source are normally used without testing if stored under conditions consistent with the supplier’s recommendations.11.18 Where a primary reference standard is not available from an officially recognized source, an “in-house primary standard” should be established. Appropriate testing should be performed to establish fully the identity and purity of the primary reference standard. Appropriate documentation of this testing should be maintained.
11.19 Secondary reference standards should be appropriately prepared, identified, tested, approved, and stored. The suitability of each batch of secondary reference standard should be determined prior to first use by comparing against a primary reference standard. Each batch of secondary reference standard should be periodically requalified in accordance with a written protocol.
Re: Use of volumetric solutions
Posted: Wed Aug 01, 2012 9:36 pm
by KM-USA
Hi
KM this is from ICH Q7a as an example:
11.17 Primary reference standards should be obtained as appropriate for the manufacture of APIs. The source of each primary reference standard should be documented. Records should be maintained of each primary reference standard’s storage and use in accordance with the supplier’s recommendations. Primary reference standards obtained from an officially recognised source are normally used without testing if stored under conditions consistent with the supplier’s recommendations.11.18 Where a primary reference standard is not available from an officially recognized source, an “in-house primary standard” should be established. Appropriate testing should be performed to establish fully the identity and purity of the primary reference standard. Appropriate documentation of this testing should be maintained.
11.19 Secondary reference standards should be appropriately prepared, identified, tested, approved, and stored. The suitability of each batch of secondary reference standard should be determined prior to first use by comparing against a primary reference standard. Each batch of secondary reference standard should be periodically requalified in accordance with a written protocol.
Krickos - thanks.
Is this in reference to a volumetric solution or a primary reference standard? Do titrants qualify as primary reference standards?