Comparison of Elisa- and LC-MS-Based Methodologies for the Exposure Assessment of Bisphenol A
Abstract
Several types of methods, mainly liquid chromatography (LC), have been used for the analysis and assessment of bisphenol A (BPA) in human biological samples. Enzyme-linked immunosorbent assay (ELISA) is also being used for BPA measurement. In this study, we verified whether ELISA is suitable for measuring human samples, namely, serum and urine, by comparing the ELISA results with those obtained by liquid chromatography with multichannel colometric electrochemical detection (LC/ECD) and liquid chromatography coupled to a mass spectrometer (LC/MS/MS). Results of the measurement with LC/ECD showed urinary BPA concentrations to be 1.92 (1.45) ± 1.99 (mean (median) ± standard deviation) ng BPA/mL without the correction of urine volume and 1.20 (0.90) ± 1.10 μg BPA/g creatinine; however, in serum, free and total BPA were not detected. In both samples, a good correlation of the values with the methods was not found. ELISA is one of the powerful measurement methods, since it is convenient and useful for screening bulk quantities. At this point, however, ELISA is not suitable for BPA measurement in human samples because of low levels of BPA in human samples, matrix effect, and specificity of anti-BPA antibody.