Table of Contents
ISRN Chromatography
Volume 2012, Article ID 487138, 7 pages
http://dx.doi.org/10.5402/2012/487138
Research Article

Simple and Fast Methods Based on Solid-Phase Extraction Coupled to Liquid Chromatography with UV Detection for the Monitoring of Caffeine in Natural, and Wastewater as Marker of Anthropogenic Impact

Department of Chemistry, University of Girona, Montilivi Campus, s/n, 17071 Girona, Spain

Received 12 December 2011; Accepted 2 January 2012

Academic Editors: I. Brondz, G. K. Jayaprakasha, H. Naranmandura, and F. Pellati

Copyright © 2012 Sònia Moret et al. This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.

Abstract

Two concentration methods for fast and routine determination of caffeine (using HPLC-UV detection) in surface, and wastewater are evaluated. Both methods are based on solid-phase extraction (SPE) concentration with octadecyl silica sorbents. A common “offline” SPE procedure shows that quantitative recovery of caffeine is obtained with 2 mL of an elution mixture solvent methanol-water containing at least 60% methanol. The method detection limit is 0.1 μg L−1 when percolating 1 L samples through the cartridge. The development of an “online” SPE method based on a mini-SPE column, containing 100 mg of the same sorbent, directly connected to the HPLC system allows the method detection limit to be decreased to 10 ng L−1 with a sample volume of 100 mL. The “offline” SPE method is applied to the analysis of caffeine in wastewater samples, whereas the “on-line” method is used for analysis in natural waters from streams receiving significant water intakes from local wastewater treatment plants.