IWC Annual Report 2003 - Institut für Wasserchemie und chemische ...

with no further functional monomer. The second group described the preparation of
MIP for 1-hydroxypyrene, based on divinylbenzene and styrene. Generally, imprinting
PAHs is difficult, because non-covalent interactions like hydrogen bond, dipolar and/or
ionic interactions cannot be formed. There only remain hydrophobic interaction, steric
cavity, and π − π interaction which are one or two orders of magnitude weaker than
the electrostatic forces.
In the first part of the project, three different monomers and two cross-linkers were
selected to synthesize six kinds of imprinted polymers. Further, both bulk polymerization
and suspension polymerization was applied. The affinity and selectivity of
the synthesized polymers to benzo(a)pyrene and nine other PAHs was investigated in
detail with rebinding, solid-phase extraction and HPLC experiments.
All the results indicate that the polarity of both monomer and cross-linker play in
important role for affinity and retention behaviour. The affinities of the polymer to
the analyte increased with the decreasing polarity of monomer and cross-linker. No
significant difference in the affinity to benzo(a)pyrene was observed between MIPs and
MIMs (molecularly imprinted microspheres). The preparation of nanoparticles and
affinity layers on sensors is presently under investigation.
(J.-P. Lai)
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