2.2.2. Analytical method to assess materials
SEA was extracted with water, concentrated by dialysis against
a polyethylene glycol solution, quantified using the double-sand-
wich ELISA developed at Anses and finally adapted by using com-
mercially available antibodies (Toxin Technology, Sarasota, USA).
Each of the six materials was analysed in triplicate. In addition, ali-
quots of the three blank materials were spiked at two levels
(0.1 ng/g, 0.3 ng/g) and analysed in triplicate. The latter experi-
ments served to establish the process recovery of SEA (overall
recovery which comprises losses during extraction (extraction
recovery) as well as influences from the ELISA analysis (calibration,
but also potential matrix effects)).