2006 Volume 55 Issue 1 Pages 1-7
A simple and rapid preparation procedure of PCBs in transformer oil in conjunction with an immunoassay using an automated instrument for detecting PCBs is described. The joint column is used to prepare PCBs. The oil sample is introduced into a primary diatomite column containing fuming sulfuric acid and sulfuric acid to degrade the hydrocarbons, besides PCBs; the resulting hydrocarbons are removed by a secondary silica column. PCBs in the elusion are then extracted by dimethyl sulfoxide for an immunoassay. This preparation procedure can be performed within 30 min., and the recovery ratio of PCBs is estimated to be in the range from 40% to 60%. PCBs can be detected with an automated immunoassay instrument after mixing the dimethyl sulfoxide extract at 1%(v/v) with an anti-PCB antibody solution. The assay is completed within 8 min. The dynamic range is, respectively, from 0.3 ppm to 18 ppm for Kanechlor 300, from 0.2 ppm to 0.7 ppm for Kanechlor 400, and from 0.1 ppm to 1.5 ppm for Kanechlor 500 and 600. This assay also enables one to detect PCBs as a total in fifteen oil samples in the range from 0.1 ppm to 1.8 ppm with a good correlation with the analysis using a high-resolution mass spectrometer.
