RQA GLP Committee
Dear Anon, it is not necessary for the analyst to be blinded, it is the person who will interpret the results who should be blinded. The analyst will have to prepare and analyse the samples but the results will be what they are and should not be influenced by the analyst - and even if they were blinded they probably could work out the difference anyway. The issue should be that the results should not be sent unblinded to anyone who should be blinded.
If you are still concerned then this would have to be considered before the samples were collected. The sample numbers should be assigned in such a way as only those who need to know, understand the system. Then the analyst would only receive what would appear to be completely randomised numbers. Either that, or once the samples have been collected, they are randomised by someone independent of the study.