PARENT SESSION

PM04 Phthalate Esters: Fate and Effects
Exhibit Hall
8:00 AM - Monday

(PM024) Development of ELISAs for the quantitative analysis of Phthalate Esters.

Hirobe, M¹, Goda, Y¹, Fujimoto, S¹, Tomita, M², Ike, M³, Fujita, M³, Rubio, F⁴, ¹ Japan EnviroChemicals, Osaka, Japan² Mie Univ., Tsu, Japan³ Osaka Univ., Suita, Japan⁴ Abraxis LLC, PA, USA

ABSTRACT- Phthalate esters, suspected to be one of endocrine disruptors, are widely used as a plasticizer found in products including certain toys and childcare articles. To investigate the fate and effects of phthalate esters, the appropriate quantitative analytical method has been desired. Phthalate esters are normally measured by gas chromatography-mass spectrometry (GC-MS) or liquid chromatography-mass spectrometry (LC-MS). These analytical methods need expensive instrumentation, extensive purification and technical expertise in operation. And the contamination of phthalate esters from any sources during the complicated analysis process (ex. phthalate esters from pretreatment tools and atmosphere) leads to less reproducible results. To overcome these problems and analyze large number of samples, enzyme-linked immunosorbent assay (ELISA) is a suitable alternative for phthalate esters determination. We have developed two monoclonal antibody (mAb) based ELISAs for diethylhexyl phthalate (DEHP ELISA) and dibutyl phthalate (DBP ELISA). To generate monoclonal antibodies for these ELISA, hybridoma cells were produced by the fusion of mouse myeloma cells and spleen cells from mice immunized with DEHP and DBP derivatives coupled to bovine serum albumin. The assay working ranges of these ELISAs are 300-2500 g/L for DEHP ELISA and 200-4000 g/L for DBP ELISA, respectively and the sample concentration was investigated with an aid of a simple solid phase extraction. The mAb for DEHP ELISA widely reacted with phthalate esters, whose alkyl chain length is 2-7, including DEHP. On the other hand, the mAb for DBP ELISA was specific to dibutyl and butyl benzyl phthalates and moderately reacted with phthalate esters whose alkyl chain length is 2-5. Further studies are being carried out in order to increase the sensitivity through improving antibodies and optimizing ELISA formats.

Key words: phthalate esters, ELISA, diethylhexyl phthalate, dibutyl phthalate