In-syringe dispersive solid-phase extraction using dissolvable layered double oxide hollow spheres as sorbent followed by high-performance liquid chromatography for determination of 11 phenols in river water

Layered double oxide hollow spheres (LDO-HSs) were synthesized and employed as a dissolvable sorbent in dispersive solid-phase extraction (DSPE) to extract eleven United States Environmental Protection Agency's priority phenols from aqueous samples. With their higher specific surface area, LDO-HSs showed much higher extraction efficiency than normal layered double hydroxides and layered double oxides. The entire extraction process was accomplished in a syringe. After DSPE, the sorbent with the analytes was isolated conveniently by directly expelling the spent sample solution out of the syringe. The analyteenriched sorbent was then subsequently dissolved by withdrawing an acidic solution into the syringe. The final extract was analyzed by high-performance liquid chromatography with ultraviolet detection. The results showed that this method provided low limits of detection for the phenols (0.005-0.153 mu g/L), good linearity (r(2) >= 0.9956) and relative standard deviations of <= 6.7%. The optimized method was applied to water samples from 3 rivers. This simple extraction procedure was demonstrated to be a fast, efficient and convenient DSPE approach. (C) 2014 Elsevier B.V. All rights reserved.