Abstract
In this study, a simple, rapid and effective in-syringe micro-solid phase extraction
(MSPE)
method was developed for the separation and preconcetration of parabens (methyl, ethyl, propyl and
butyl paraben) in environmental water samples. The parabens were determined and quantified using
high performance liquid chromatography and a photo diode array detector (HPLC-PDA). Chitosan-coated
activated carbon (CAC) was used as the sorbent in the in-syringe MSPE device. A response surface
methodology based on central composite design was used for the optimization of factors (eluent
solvent type, eluent volume, number of elution cycles, sample volume, sample pH) affecting the
extraction efficiency of the preconcentration procedure. The adsorbent used displayed excellent
absorption performance and the adsorption capacity ranged from 227–256 mg g−1. Under the optimal
conditions the dynamic linear ranges for the parabens were between 0.04 and 380 µg L−1. The limits
of detection and quantification ranged from 6–15 ng L−1 and 20–50 ng L−1, respectively. The
intraday (repeatability) and interday (reproducibility) precisions expressed as relative standard
deviations (%RSD) were below 5%. Furthermore, the in-syringe MSPE/HPLC procedure was validated
using spiked wastewater and tap water samples and the recoveries ranged between from 96.7 to 107%.
In conclusion, CAC based in-syringe MSPE method demonstrated great
potential for preconcentration of parabens in complex environmental water.