Fluorous receptor-facilitated solid phase microextraction

Abstract

Solid phase microextraction (SPME) is a widely accepted solvent-free extraction technique that usually uses a polymer sorbent as the extraction phase. In this work, we have developed receptor-doped fluorous films for solid phase microextraction. The hydrophobic and lipophobic properties of the fluorous films in principle reduce the polymer–water distribution coefficients of solutes other than those that can form noncovalent interactions with the fluorous receptor. This strategy should improve extraction selectivity. We found that the addition of a fluorous carboxylic acid (Krytox 157 FSH) to a fluorous film (Teflon AF 2400) increased the polymer–water distribution coefficients of quinoline, a nitrogen heterocycle. We studied the effects of receptor concentration and solute concentration on the distribution coefficients based on 96-well vessel SPME. We then coated this receptor doped fluorous polymer on a stainless steel fiber for SPME. Compared to a commonly used SPME fiber made of polydimethylsiloxane (PDMS), it showed a preference for the nitrogen heterocyclic compound over a non-heterocyclic control, phenol. To our knowledge, this is the first reported receptor-doped fluorous SPME.