AOAC SPIFAN Nutrients ERP Review (March 14, 2019)

Fluor-03 (Feb. 2019) FOR ERP USE ONLY DO NOT DISTRIBUTE

Figure 2 Principle of the patented Stopped-Flow Dialysis [1] showing the sample flow on the left side of the membrane and the acceptor solution with the dissolved analytes. The concentration in the acceptor solution matches the concentration in the original solution. As the acceptor side contains only dissolved analytes this solution can be directly injected into the IC.

(d) Dialysis parameters. —Dialysis and sample transfer time ( Table 6 ) are evaluated at the beginning of the analysis (see Figure 3 ). Controls of the set-up should be run periodically. Thereby a medium concentrated check standard should be injected three times with a transfer time variation of ± 5 s.

Table 6 Dialysis parameters

Dialysis time (min) Transfer time (s)

9

30

Dialysis time (7 to 12 min, step of 1 min)

Transfer time (20 to 60 s, step of 5 s)

Figure 3 Dialysis parameter determination

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