Determination of phenolic compounds in natural waters by liquid chromatography with ultraviolet and electrochemical detection after on-line trace enrichment

The eleven phenolic EPA priority pollutants were determined by liquid chromatography followed by UV and electrochemical detection. Modified on-line trace enrichment was used to detect lower concentrations of phenolic compounds, which enables stronger sorbents to be used without broadening the peaks. PLRP-S and a highly cross-linked styrene-divinylbenzene copolymer were compared for the on-line trace enrichment. Higher breakthrough volumes were obtained with the latter sorbent but the selectivity was lower. The performance of the methods developed was checked with tap and river water and the methods studied enabled phenolic compounds at levels of 0.1 mu g l(-1) to be determined in real samples. The repeatability and reproducibility between days (n = 5) for real samples spiked at 1 mu g l(-1) were lower than 10%.