Mixed sorbent phases for thick film open tubular traps

In this work, we present a technique for the preparation of tailor-made sorbent phases for thick film open tubular traps. Solid or liquid polymers are dispersed in a polydimethylsiloxane (PDMS) pre-polymer, which is cross-linked in situ after coating. The technique is evaluated by preparing thick film open tubular traps with PDMS containing solid or liquid poly(ethylene glycol) (PEG). A significant increase in retention for polar analytes is observed, even when only 7.5% PEG is present. The increase in retention for 3-chloro-1,2-propanediol is more than tenfold. The preparation method is simple and no solvents are required. Also, the concept provides great flexibility in terms of phase composition.