Synthetic approaches to parabens molecularly imprinted polymers and their applications to the solid-phase extraction of river water samples.
In this paper we describe the synthesis, characterisation and use of two distinct molecularly imprinted polymers (MIPs) prepared using esters of p-hydroxybenzoic acid (parabens) as templates: one MIP was synthesised by precipitation polymerisation using a semi-covalent molecularly imprinting strategy with methyl paraben as the template/target (MIP 1); the second MIP was prepared in monolithic form through a conventional non-covalent molecular imprinting strategy, with butyl paraben as the template (MIP 2). MIP 1 recognized methyl paraben, showed cross-selectivity for other parabens analytes used in the study and higher affinity towards these compounds than did a non-imprinted control polymer. Similarly, MIP 2 demonstrated higher affinity towards paraben analytes than a non-imprinted control polymer. For the analysis of environmental water samples, a solid-phase extraction (SPE) protocol was developed using MIP 2 as sorbent, and results were compared to a SPE using a commercial sorbent (Oasis HLB). With MIP 2 as sorbent and butyl paraben as target, when percolating 500 mL of river water spiked at 1 μg L(-1) through the SPE cartridge, and using 1 mL of isopropanol as cleaning solvent, a higher recovery of butyl 4-hydroxybenzoate (butyl paraben) and a cleaner chromatogram where achievable when using the MIP compared to the commercial sorbent.
Beltran
A
A
Departament de Química Analítica i Química Orgànica, Universitat Rovira i Virgili, Marcel·lí Domingo s/n, Campus Sescelades, 43007 Tarragona, Spain.
Marcé
R M
RM
Cormack
P A G
PA
Borrull
F
F
D054802:Molecular Imprinting / Q000379:methods*; D010226:Parabens / Q000032:analysis* / Q000302:isolation & purification; D011108:Polymers / Q000138:chemical synthesis / Q000737:chemistry*; D045483:Rivers / Q000737:chemistry*; D052616:Solid Phase Extraction / Q000379:methods*
D010226:Parabens; D011108:Polymers; C038091:butylparaben; C038193:4-hydroxybenzoic acid