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Malachite Green Laboratory Methods
Amendment:
Application of Laboratory Information Bulletins
4333 and 4334 for the Determination of
Leucomalachite Green and
Malachite Green Residues in Catfish, Basa, Tilapia, Trout, and Shrimp
Wendy C. Andersen, Sherri B. Turnipseed, and José E. Roybal
A modified extraction was validated by LC-VIS and LC-MS
n
for LMG and MG residues in catfish, basa, tilapia, trout, and shrimp, and
was verified in eel. To achieve high residue recoveries in these species,
the following changes should be made to the salmon extraction detailed in
LIB 4334 (page 7):
- Increase the quantity of alumina used in the initial extraction from 6 g to 10 g.
- In the liquid-liquid extraction step, let phases separate for a maximum of 10 minutes (salmon method states 15 minutes minimum).