Sticking pump valves? [Bioanalytics]

posted by Ladi – Thailand, 2018-07-16 06:14  – Posting: # 19063
Views: 923

Dear Helmut,

Thank you for the valuable troubleshooting insight and tactics. We actually called the service technician and he replaced the check valve. But will surely do more before calling technician next time.

» IMHO, you can (and should) have an SOP for reanalysis or reinjection (if stability of extracts is validated).

May I ask you and other members about reinjecting or reanalysis of samples when these things happens?
From The AAPS Journal, Vol. 16, No. 6, November 2014 (page 1170-1171) and The AAPS Journal, Vol. 16, No. 5 September 2014 (page 892) which says that partial batch reinjection is possible, providing it has been tested during validation.

From the past bad experience, we have had issues some study samples (sometime 1-2 QC samples in between too) in an analytical run do not have reportable data due to sensitivity/connection loss in the middle of the run or poor chromatograms. However, CC/QC/IS deviation pass-overall acceptance criteria. For example, Time point 1-12 has data/ good chromatograms, Time point 13-15 has no data or poor chromatograms, Time point 16-20 has data/ good chromatograms again. In these kind of situation, can we have procedure in SOP to partial reinject those problematic samples? Please advice what action should be taken?

Option A- partial reinjection
1) Have some steps in fixing instrument and testing it.
2) Re-run the system suitability test.
3) Reinject a passing QC sample against the previous injected Calibration curve.
4) Re-inject those problematic samples.
5) Re-inject more QC that bracket those problematic samples.
6) If overall run do not pass, do full reinjection from the calibration curve (if stability still valid)

Option B- partial reanalysis
1) Accept the run.
2) Have some steps in fixing instrument and testing it.
3) Repeat analysis those problematic samples only.

Option C- Full Reinjection
1) Have some steps in fixing instrument and testing it.
2) Reinject whole run starting from system suitability test and also Calibration curve.

Option D- Full Reanalysis

1) Have some steps in fixing instrument and testing it.
2) Reanlysis all samples since instrument goes bad in the middle of the run is not acceptable.

Any suggestions or comment is appreciated.


Edit: White papers of the Global Bioanalysis Consortium Harmonization Team linked. [Helmut]

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