β-Cyclodextrin epichlorohydrin copolymer as a solid-phase extraction adsorbent for aromatic compounds in water samples

A novel solid-phase extraction (SPE) procedure for trace aromatic compounds in water samples has been developed using 12 aromatic compounds as model compounds and GC-MS and UV spectrophotometry for detection. The method is based on the fact that β-cyclodextrin (β-CD) epichlorohydrin (ECH) copolymer (β-CDEP) can extract non-ionized aromatic compounds quantitatively from aqueous samples. The polymer used is a colorless, transparent and insoluble solid with a maximum capacity of 0.82 μmol aromatic compounds per gram. It was synthesized by co-polymerization of β-CD and ECH and characterized by FT-IR and UV. β-CDEP does not contain double bonds, and therefore it does not have appreciable absorbance in the UV region. The optimum pH range for the extraction of aromatic compounds is 2.5-5.0. The method has high extraction efficiency with the recoveries between 90 and 101% for aromatic compounds at 0.02-1.67 ppm levels, and the analytes can be easily eluted by methanol washing after preconcentration.