Development of On-Line Solid Phase Extraction (SPE) Coupled with High-Performance Liquid Chromatography (HPLC) for the Determination of Phenols in River Water

Abstract

A method is reported based on a novel adsorbent for the determination of five phenols in river water by on-line solid-phase extraction (SPE) coupled with high-performance liquid chromatography. Acryloyl-β-cyclodextrin and N-isopropylacrylamide were grafted to the silica surface to prepare the adsorbent that was placed in a laboratory-constructed double-pass screw column (10 mm × 2 mm, i.d.) for on-line SPE. In addition, to obtain the optimum on-line SPE conditions, the sampling flow rate, sample volume, eluent flow rate and time, and methanol ratio in the eluent were investigated. Under the optimal experimental conditions, the response of the method was linear for phenol concentrations from 0.1 to 500.0 ng mL−1. The limits of detection were between 0.080 and 0.72 ng mL−1 and the limits of quantification from 0.27 to 2.4 ng mL−1. The intra-day and inter-day relative standard deviations were from 1.1% to 4.9% (n = 3) and 1.5% to 5.7% (n = 3), respectively. The spiked recoveries of the river water samples were from 87.5% to 111%. This adsorbent was suitable for the preconcentration of trace phenols from aqueous solution. The established method was simple, time-saving, automated, and cost-effective.