Development of a liquid chromatography-tandem mass spectrometry method for quantification of the egg allergen ovalbumin in rat plasma

Dear Editor, Monitoring of serum concentrations of food allergens during challenge tests provides important information when diagnosing food allergies. Sandwich ELISA has been used to measure the concentrations of food allergens in foodstuffs and in biological samples. However, the antibodies used in ELISA sometimes show cross-reactivity and/or interference with multiple components in samples, resulting in overestimation and/or underestimation. Thus, the widespread use of ELISA is limited because of poor specificity. Recently, liquid chromatography tandem mass spectrometry (LC-MS/MS) has been used for the analysis of food allergens in processed foods. These reports suggest that detection of food allergens in processed foods using mass spectrometry (MS) is helpful for quality control. Furthermore, MS has been used for quantification of biological origin peptides and protein-based biopharmaceuticals in biological samples. However, there are no studies that the plasma (or serum) concentrations of food allergens were measured using MS. Compared to the detection of food allergens in processed foods using MS, detection of allergen in plasma is complicated since concentrations of food allergen in plasma are generally much lower than those in processed foods.