Stir bar sorptive extraction (SBSE), a novel extraction technique for aqueous samples: Theory and principles

TLDR

The paper presents the theory and practice of stir bar sorptive extraction (SBSE) using PDMS‑coated stir bars for sample enrichment. SBSE employs 10‑mm and 40‑mm PDMS‑coated stir bars, with equilibration times of 30–60 min, to extract volatile and semivolatile micropollutants from aqueous samples, and is compared to solid‑phase microextraction. 10‑mm stir bars are optimal for 10–50 mL samples, 40‑mm bars for up to 250 mL, and SBSE achieves low‑ng/L detection limits, reaching below 0.1 ng/L for 200‑mL samples. © 1999 John Wiley & Sons, Inc., J Micro Sep 11: 737–747.

Abstract

The theory and practice of a novel approach for sample enrichment, namely the application of stir bars coated with the sorbent polydimethylsiloxane (PDMS) and referred to as stir bar sorptive extraction (SBSE) are presented. Stir bars with a length of 10 and 40 mm coated with 55 and 219 μL of PDMS liquid phase, respectively were applied. The 10-mm stir bars are best suited for stirring sample volumes from 10 up to 50 mL whereas 40-mm stir bars are more ideal for sample volumes up to 250 mL. Depending on sample volume and the stirring speed, typical stirring times for equilibration are between 30 and 60 min. The performance of SBSE is illustrated with the analysis of volatile and semivolatile micropollutants from aqueous samples. Detection limits using mass selective detection are in the low ng/L range for a wide selection of analytes from the EPA priority pollutant lists including analytes ranging in volatility from 1,1,1-trichloroethane to chrysene. For the extraction of selected compounds from 200-mL samples, detection limits below 0.1 ng/L are reached in the selected ion monitoring mode. A comparison between SBSE and solid-phase microextraction is made. ©1999 John Wiley & Sons, Inc. J Micro Sep 11: 737–747, 1999