Reason/Issue |
Following a customer complaint about coloured eluates, bioMérieux's investigation confirmed an issue with a single lot of NucliSENS Lysis Buffer. The eluate becomes coloured because of the presence of the heme group from the haemoglobin present in whole blood samples including Dry Blood Spots. The root cause of the coloration is linked to the pH that, for the affected lot, has been observed to be 6.9 instead of 7.1 +/-0.1 as per product specification. The presence of haemoglobin causes the inhibition of the PCR. The result in most of the cases is uninterpretable test results as the Internal Control (IC) would also be inhibited, invalidating the test. In this case, there is a potential risk of delayed results. Considering that the Buffer is used in various protocols and downstream applications, and the worst case scenario in which the IC would not be inhibited, or not used although it is part of good laboratory practices, the tests run could potentially result in false negative results. |