Only for QCs; encouraged ≠ required [Bioanalytics]

posted by dshah – India, 2020-08-03 09:17 (122 d 00:08 ago) – Posting: # 21818
Views: 2,108

Hi Helmut!
As per standard SOP - "If the response of internal standard in a sample varies by more than 60% for the isotopically labeled internal standard from the mean ISTD response of CC and QC samples of a particular entire run, then repeat the analysis of the sample under reason Significant variations in response of internal standard"
However - there is no guideline which specifies the limit for variation for IS. Thus, it could be 30/40/50/60 - as per CRO's SOP/requirement/Experience.
The interesting thing could be - whether the QC's analyte/IS standard response are within acceptable range - i.e. whether the QC's were acceptable? if the IS standards response are high, there is possibilities that the QC will be on lower side. I am wondering what other things can be directly correlated and what can be the reason for CRO's acceptability of variation in IS response?

Complete thread:

 Admin contact
21,232 posts in 4,427 threads, 1,482 registered users;
online 7 (0 registered, 7 guests [including 1 identified bots]).
Forum time: Thursday 08:26 CET (Europe/Vienna)

Every man is fully satisfied that there is such a thing as truth,
or he would not ask any question.    Charles Sanders Peirce

The Bioequivalence and Bioavailability Forum is hosted by
BEBAC Ing. Helmut Schütz