Powerful preconcentration method for capillary electrophoresis and its application to analysis of ultratrace amounts of polycyclic aromatic hydrocarbons

• Published in: Analytical and bioanalytical chemistry 2006-07, Vol.385 (5), p.888-894
• Main Authors: Takagai, Yoshitaka, Akiyama, Ryoutaro, Igarashi, Shukuro
• Format: Article
• Language: English
• ISSN: 1618-2642; 1618-2650
• DOI: 10.1007/s00216-006-0447-9

For environmental analyses, a high-performance and powerful preconcentration system exceeding 1 x 10(7)-fold was developed that was composed of a blue cotton method (solid extraction method)/homogeneous liquid-liquid extraction method/on-line concentration method for capillary electrophoresis (CE). This system was named the "triplex concentration system" and it was achieved by finding a new phase-separation phenomenon (homogeneous liquid-liquid extraction) from a water-miscible organic solvent. Parts per trillion levels of polycyclic aromatic hydrocarbons (PAHs) were used as model analytical targets in this study. With the proposed method, 20-L levels of environmental water could be preconcentrated up to 1 x 10(7)-fold within a maximum of 1 h. The parts per trillion levels of PAHs were easily determined even using UV/CE, which has a serious sensitivity problem, and the detection limit of benzo[a]pyrene was 3.60 ppt. This system was also used as a practical monitoring method for the Miyata River (in Japan).