| Abstract
| - Matrix solid-phase dispersion (MSPD) is a new samplepretreatment for solid samples. This technique greatlysimplifies sample pretreatment but, nonetheless, theextracts often still require an extra cleanup step that isboth laborious and time-consuming. The potential ofcombining MSPD with molecularly imprinted solid-phaseextraction (MISPE) was investigated in this study. Liversamples were ground in a mortar with C18 sorbent andthe homogenized mixture packed into an SPE cartridgeand placed on top of a MISPE cartridge. Subsequently,clenbuterol was eluted from the MSPD cartridge onto theMISPE cartridge using acetonitrile containing 1% aceticacid. The ability of the molecularly imprinted polymer toselectively adsorb analyte in acetonitrile was exploited forre-extracting clenbuterol directly from this acetonitrileextract via the double cartridge tandem system. Theanalyte was eluted from the MISPE cartridge using acidified methanol. A clear eluate was obtained, which wassubsequently evaporated, redissolved, and analyzed byHPLC electrochemical detection (ECD) or ion trap massspectrometry (LC/IT-MS). The MISPE cartridge used inthis study was imprinted using bromoclenbuterol, astructural analogue of clenbuterol, as the template. TheseMISPE cartridges showed excellent stability. The complete extraction procedure was rapid, and recoveriesexceeded 90% for the target analyte. The method detectionlimit for the LC/IT-MS procedure was < 0.1 μg/kg. Thismethod, therefore, satisfies the stringent requirements ofEuropean Union regulation EEC 2377/90.
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