Abstract:
A novel method was developed for the direct determination of trace polychlorinated biphenyls(PCBs)in seawater samples using a hydrofluoric acid etched stainless steel wire as a fiber of solid-phase microextraction(SPME)coupled with gas chromatography(GC). The parameters influencing the extraction and efficiency, including extraction time, extraction temperature, stirring rate, desorption temperature and desorption time were optimized. The linear range of the method could reach two orders of magnitude with correlation coefficients higher than 0.99 except PCB198. The linear ranges for PCB28 and PCB52 were from 1.0 to 100.0 ng/L, and the linear ranges for 8 other PCBs were from 0.5 to 50.0 ng/L. The limits of detection were in the range of 0.01-0.10 ng/L. The relative standard deviations were 2.4%-7.2% for a single fiber and 4.9%-8.7% for fiber-to-fiber.The recoveries were 80.9%-106.0% for 10 PCBs standard in seawater samples. High mechanical stability, good seawater corrosion resistance, long life time and low cost were some advantages of the etched stainless steel wire fiber. The proposed method was simple, rapid and sensitive, and it was suitable for determining the trace PCBs in seawater samples.