Membrane Solid-Phase Microextraction—A New Concept of Sorbent Preparation

Abstract

A new sorption system for isolation/enrichment of polar organic analytes from aqueous samples was obtained by substantial modification of the solid-phase microextraction (SPME) probe. In this system, polar sorbents are separated from the sample by a hydrophobic membrane. The new membrane SPME (M-SPME) probe was made utilizing polyethylene glycol (PEG) (molecular weight = 20 kDa) and polydimethylsiloxane (PDMS) as the membrane material. In this probe, PEG behaves as a pseudo-liquid at the extraction stage, whereas, up to now, it has mainly been used as a cross-linked solid adsorbent. It has been found that such M-SPME fiber may be successfully used at the sample pretreatment stage. It is sufficiently robust and thermally stable; the latter feature permits the usage of thermal desorption for the liberation of analytes. Comparison of our probe with the commercially available polyacrylic (PA) SPME fiber, using a mixture of phenols and gas chromatography as the final determination technique, demonstrated the highly effective nature of the new sorptive system; ca. 10 times higher than in the case of the PA fiber.

Preparation and characterization of porous carbon material-coated solid-phase microextraction metal fibers

“…For the fiber prepared with direct coating method, the extraction efficiency of the coating is determined by the properties of the analytes and the used sorbent. Using a hydrophobic polymer membrane to separate sorbent and sample was proved to be an effective method to protect polar sorbent [44], but our experimental results showed that the extraction efficiency of the sorbent might be decreased.…”

High-Quality Metal–Organic Framework ZIF-8 Membrane Supported on Electrodeposited ZnO/2-methylimidazole Nanocomposite: Efficient Adsorbent for the Enrichment of Acidic Drugs

“…The equilibrium time for low concentration ibuprofen was somewhat longer than that for high concentration. According to Fick’s law, the diffusion of low concentration of analytes across the ZIF-8 membrane slowed down47. Moreover, the adsorption capacity significantly increased as the initial concentration of ibuprofen increased, indicating the favorable adsorption at high concentrations.…”

Green Sample Preparation Techniques for Chromatographic Determination of Small Organic Compounds

“…high density polymers which resemble viscous fluid are used as an extrahent in this two-phase sorption system. The analytes are retained on the fiber via dissolution in the extraction medium [10], [11].…”