Analytical Sciences

Abstract − Analytical Sciences, 20(1), 133 (2004).

Improved Detectability with a Polymer-based Trapping Device in Rapid HPLC Analysis for Ultra-low Levels of Bisphenol A (BPA) in Environmental Samples
Yoshiyuki WATABE,* Takuya KONDO,** Hiroe IMAI,** Masatoshi MORITA,** Nobuo TANAKA,* Jun HAGINAKA,*** and Ken HOSOYA* 
*Department of Polymer Science & Engineering, Kyoto Institute of Technology, Matsugasaki, Sakyo-ku, Kyoto 606-8585, Japan
**Endocrine Disrupters Research Laboratory, National Institute for Environmental Studies, 16-2 Onogawa, Tsukuba, Ibaraki 305-8506, Japan
***Faculty of Pharmaceutical Sciences, Mukogawa Women's University, 11-68 Koshien Kyuban-cho, Nishinomiya, Hyogo 663-8179, Japan
A new high-performance liquid chromatography (HPLC) method has been developed to detect ultra-low concentrations of bisphenol-A (BPA) (below 1 ng/L (ppt)) using column switching electrochemical detection (ECD). The results were superior to those obtained from manual pretreatment procedure with membrane stationary phase. BPA is inherently ubiquitous in the environment, including tools and solvents used for its analysis; to obtain meaningful results, therefore, the concentration of the overall BPA contamination must be below the detection limit for BPA using the analytical system. Therefore, purified water for preparing the standard BPA solution must be filtered with a hydrophobic membrane to suppress BPA background levels of contamination. In addition, we investigated methods for effectively preserving environmental water containing BPA. The addition of a small amount of ethylenediaminetetraacetic acid (EDTA) provided good recovery even after overnight storage. By employing these precautionary measures and procedures to reduce BPA contamination from the analytical procedure, we could accurately determine 1 - 10 ppt of BPA in environmental water samples using a column switching HPLC system.