Improved rapid extraction method for fish and shrimp and water samples that offers high recovery rates
- 96-well high throughput quantitative detection method
- Sensitive - detection limit of 0.1 ppb for fish and shrimp samples
- High reproducibility
- Samples can be directly used for liquid chromatography confirmation
Protocol for the Screening of Malachite Green/Leucomalachite Green
The proprietary MaxSignal® Malachite Green/LMG ELISA Kit is designed for routine screening for Malachite Green/Leucomalachite Green in fish, shrimp, fish/shrimp feed, fish oil and water samples of fish farms or fishponds. The MaxSignal® Malachite Green/LMG ELISA Test is the only procedure described for screening samples for MG contamination in the USDA’s Chemistry Laboratory Guidebook which contains test methods used by FSIS Laboratories to support the Agency's inspection program, ensuring that meat, poultry, and egg products are safe, wholesome and accurately labeled. The pdf describing the protocol (Method Number R44a, Screening for Malachite Green and Crystal Violet by ELISA) can be read in the USDA’s Chemistry Laboratory Guidebook or downloaded HERE.
The method is based on a competitive colorimetric ELISA assay. The Malachite Green (MG) antibody has been coated in the plate wells. During the analysis, sample is added along with the MG-Biotin Conjugate. If the MG residue is present in the sample, it will compete for the MG antibody, thereby preventing the MG-Biotin from binding to the antibody attached to the well. After washing the wells, Streptavidin-horseradish peroxidase (Streptavidin-HRP) is added. The Streptavidin-HRP will bind with the MG-Biotin attached to the MG antibody. The resulting color intensity, after addition of the HRP substrate (TMB), has an inverse relationship with the MG residue concentration in the sample.
Malachite Green (Basic Green 4) has been widely used all over the world in the fish farming industry as a fungicide, ectoparasiticide and disinfectant. However, Malachite Green is highly cytotoxic to mammalian cells and also acts as a liver tumor-enhancing agent. This has led to a prohibition of Malachite Green for the treatment of fish and shrimp used for food production.
Contia, G. O., Chiara Copata, C., Wangb, Z., D’Agatia, P., Cristaldia, A. and Ferrantea, M. (2014) Determination of illegal antimicrobials in aquaculture feed and fish: An ELISA study. Food Control. Doi: 10.1016/j.foodcont.2014.10.050
Yang, MC, et. al. (2007) Production of antibodies for selective detection of malachite green and the related triphenylmethane dyes in fish and fishpond water. J. Agric. Food Chem. 55(22): 8851-6.
This kit is manufactured to the international quality standard ISO 9001:2008.
PLATE: 1 x 96 well (Removable 8 wells x 12 strips)
TESTS PER KIT: The kit has the capacity for 96 determinations or testing of 42 samples in duplicate
SHELF LIFE & STORAGE: 12 months when properly stored
Validation of MG ELISA results by LC-MS method using fish sample
Correlations between ELISA and LC-MS: y= 0.97x + 0.015; r2 = 0.99 (y: LC-MS; x: ELISA)
MaxSignal® Malachite Green/LMG ELISA Detection Limits