Inter-laboratory comparison of Cry1Ab toxin quantification in MON 810 maize by enzyme-immunoassay

Journal or Publishing Institution: Food and Agricultural Immunology

Study: http://www.tandfonline.com/doi/abs/10.1080/09540105.2011.604773#.UiDtLknD9lY

Author(s): Székács, A., Weiss, G., Quist, D., Takács, E., Darvas, B., Meier, M., Swain, T. and Hilbeck, A.

Article Type: Peer Reviewed Study

Record ID: 2252

Abstract: A laboratory ring trial was performed in four laboratories for determination of Cry1Ab toxin in leaf material of MON 810 maize using a standardised enzyme-linked immunoassay protocol. Statistical analysis was carried out by the ISO 5725-2 guidelines, sample standard deviation and standard error, within-laboratory and inter-laboratory SD and SE were calculated. Measured inter-laboratory average values were 12.5±4.0, 15.3±4.6 and 72.6±17.8 µg/g for three lyophilised samples, and 27.8±4.3 µg/g for a frozen sample, yet, Cry1Ab concentrations ranged 66.5–160.1% of the corresponding IA. Determined concentrations by in-house protocols were statistically not different in one laboratory and different in two laboratories from the corresponding values by the joint protocol. Results emphasise the importance of a standardised protocol among laboratories for comparable quantitative Cry1Ab toxin determination. However, even when using a standardised protocol, significant differences still occur among toxin concentrations detected in different laboratories, although with a smaller range of variation.

Keywords: Bacillus thuringiensis , Cry1Ab toxin, GM plants, MON 810, freeze drying, leaves, cooperative research, enzyme-linked immunosorbent assay, laboratories, Enzyme immunoassays, Immunoenzyme Techniques, Zea mays, Immunoassays, Sampling, Statistical analysis, Enzymes, plants, Zea mays, analysis, ELISA, entomopathogenic bacteria, entomopathogens, genetic engineering, genetically engineered organisms, guidelines, identification, immunoassay, maize, natural enemies, pathogens, quantitative analysis, standard deviation, standardization, techniques, toxins, transgenic plants, transgenics, Bacillus, bacterium, corn, genetic manipulation, genetically engineered plants, genetically modified organisms, genetically modified plants, GEOs, GMOs, recommendations, statistical methods, transgenic organisms

Citation: Székács, A., Weiss, G., Quist, D., Takács, E., Darvas, B., Meier, M., Swain, T. and Hilbeck, A., 2012. Inter-laboratory comparison of Cry1Ab toxin quantification in MON 810 maize by enzyme-immunoassay. Food and Agricultural Immunology, 23(2), pp.99-121.