NATA


Carry-over Effect of High Titer Analytes from General Chemistry Analysers

Laboratories should be aware of the possibility that general chemistry analysers which do not employ disposable tips on their sample probes may cause sample contamination due to carry over of a number of high titer analytes from previous samples. This is due to inadequate washing of the sample probes.

This issue may be problematic where primary tubes which may have been contaminated are subsequently tested for analytes such as AFP, β-hCG, HBsAg and PSA. The carry over effects may cause false positive results in these primary tubes.

Where laboratory procedures allow primary samples to be initially tested on general chemistry analysers and subsequently tested for these analytes, the laboratory's analyser verification procedures must investigate the possibility of carry-over effects.

This data must be available for review at assessment, whether the analyser is already established within the laboratory or is newly installed.
Should the manufacturer have previously performed such studies on an analyser type at other sites which shows minimal carry-over effects the records for these studies should be available for review at assessment.


Should you have any questions please do not hesitate to contact
Mr Andrew Griffin
Deputy Sector Manager, Life Sciences
NATA
Level 1, 675 Victoria Street
Abbotsford VIC 3067
Ph (03) 9274 8200
E-mail This email address is being protected from spambots. You need JavaScript enabled to view it.

or Mr Neil Shepherd
Sector Manager, Life Sciences
NATA
Level 1, 675 Victoria Street
Abbotsford VIC 3067
Ph (03) 9274 8200
E-mail This email address is being protected from spambots. You need JavaScript enabled to view it.