Quantification of Cry1Ab protein in genetically modified plants based on immunoaffinity magnetic bead enrichment and high-performance liquid chromatography–tandem mass spectrometry

Abstract

Quantification of Cry1Ab in genetically modified (GM) plants based on immunoaffinity magnetic bead enrichment and high-performance liquid chromatography–tandem mass spectrometry was developed. The active concentration of Cry1Ab standard solution was determined via surface plasmon resonance. Magnetic beads coated with Cry1Ab monoclonal antibodies were used for affinity enrichment of the target protein from samples. After trypsin digestion, quantification was performed by LC-MS/MS with internal standards, showing the recovery rate of (93.2 %–110.69 %) and relative standard deviation of (2.4 %–4.8 %, n = 12). The limit of detection was 5.7 ng/mL, and the limit of quantification was 22.5 ng/mL. The method was further validated by comparing the measured Cry1Ab concentrations in GM soybean and corn leaves with those obtained using ELISA. This method enables facilitating accurate quantitation of Cry1Ab and the assessment of environmental impact, pest control efficacy, and safety of GM crops.