Novel ELISA for the measurement of immunoreactive bisphenol A

In the present study, anti-BPA serum RY 504 with high titer was raised in a rabbit using BPA mono-glutaryl-KLH conjugate as immunogen. ELISA was developed using above anti BPA serum RY 504 in 1:5,000 dilution, BPA as standard and HRP labeled BPA (BPA monoglutaryl HRP) as labeled antigen. The assay range was from 0.5 ng/ml to 5,000 ng/ml of BPA. The range of the intra- and inter-assay coefficients of variation were 3.6 to 10.8 % and 6.3 to 8.4 %, respectively. Further, we compared BPA concentration obtained from the HPLC analysis of glucronidase-treated urine of human subjects ingested coffee from a commercial coffee-containing can, with IR-BPA measured directly by ELISA using the same urine sample, which was not treated with glucronidase. The results showed the positive linear correlation between both values, indicating strongly that the present ELISA can be efficiently utilized for the measurement of IR-BPA in samples in the environment including urine and plasma.