Determination of aflatoxin M1 using a dialysis-based immunoaffinity sample pretreatment system coupled on-line to liquid chromatography. Reusable immunoaffinity columns.
A liquid chromatographic column-switching system containing a dialysis unit and an anti-aflatoxin immunoaffinity precolumn (immuno precolumn) is described for the automated determination of aflatoxin M1 in milk samples. Both a flat membrane dialysis unit working according to the flowing donor-flowing acceptor principle and a laboratory made hollow-fibre dialysis unit working according to the stagnant donor-flowing acceptor principle were evaluated. The hollow-fibre unit is superior with respect to repeatability (3% relative standard deviation) and detection limit (10 ng/l for aflatoxin M1 in milk), in spite of the fact that the overall recovery is only 6%. Interfering compounds, which would destroy the activity of the immuno precolumn, are efficiently removed from the system by the dialysis step; a single immuno precolumn can then be used for over 70 milk analyses. No decrease in the performance of either the immuno precolumn or the hollow-fibre dialysis unit is observed.
Farjam
A
A
Department of Analytical Chemistry, Free University, Amsterdam, Netherlands.
van de Merbel
N C
NC
Nieman
A A
AA
Lingeman
H
H
Brinkman
U A
UA
D016607:Aflatoxin M1 / Q000032:analysis*; D000818:Animals; D002846:Chromatography, Affinity / Q000295:instrumentation / Q000379:methods*; D002853:Chromatography, Liquid / Q000379:methods*; D008892:Milk / Q000032:analysis
D016607:Aflatoxin M1