## 3 Applications in Food Safety
### Preparative Solutions
This type of extraction is introduced for high throughput as a miniaturized version of the SPE cartridge. Furthermore, the monolith plug eliminated the need for frits, a potential source of secondary adsorption. Finally, monolithic material sorptive extraction, the so-called MonoTrap, appears as a modern commercially available option in both disk and rod formats. Theses monoliths may be applied in the headspace of a vial (volatile compounds) or under agitation immersed in a solution, the extraction times usually being relatively long [47]. On the other hand, the PMME procedure can be performed on-line, as well, using stainless steel and/or capillary monolithic columns. On-line fully automated polymer monolith microextraction was performed to separate melamine residues present in milk products and eggs and successfully coupled to HPLC determination [34]. The monoliths were synthesized inside capillary columns. A different approach is the on-line purge-and-trap, and trap extraction only, using capillaries filled with monolith and coupled to GC separations, has also been reported [38, 45]. In the GC oven, one end of the absorbed monolith capillary was connected to a bare fused silica tubing that was inserted into the injection port of GC, and the other end was connected similarly to a GC column. Both the advantages of molecularly-imprinted polymers (MIPs) and solid-phase extraction (SPE) are frequently combined for sample clean-up, exhibiting good extraction efficiency, reusability and selectivity. Conventional sorbents usually develop non-specific interaction sites that lead to the co-extraction of interfering compounds. To overcome this problem, MIPs have also become increasingly attractive options for monolithic materials [32, 68]. Novel formats include MIP monoliths prepared in a stainless steel column, in a tip of a micropipette or in fused-silica capillaries by _in situ_ polymerization. Thus, the monolith may be used directly as the SPE sorbent with no need for crushing or sieving. MIP monoliths prepared inside stainless steel chromatographic columns appear as interesting pre-columns for on-line clean-up and the preconcentration of analytes. As an example, [PERSON] _et al._ developed a method to extract fluoroquinolones (FQs) present in milk and honey using an on-line MIP-based monolithic precolumn [28, 43]. By using this MIP monolith, FQs were selectively isolated from biological samples, and the impurities were eliminated simultaneously, showing high selectivity and sufficient accuracy to be used on trace levels of FQs analysis in biological samples. On-line extraction can be performed also using monolithic capillary columns, as has been demonstrated by [PERSON] _et al._ 2014 [50]. In this study, a monolith was grafted with MIP material and applied to the on-line isolation of aflat. MIPs can also be synthesized as fibers. MIP monoliths of the desired length are obtained, the thickness depending on the inner diameter of the capillary used. These fibers have been used for SPME of food samples, as in a recent method developed to determine the insecticide, chlorpyrifos, in fruits [69]. A common limit for most of these fibers is their fragility, but in this case, the MIP fiber proved to be firm and stable. A relatively new approach is the preparation of MIP monoliths inside a pipette tip and matched to a syringe for performing the polymer monolith microextraction [6, 37, 40, 46, 51]. Pipette tip-based molecularly-imprinted polymer monolith microextraction (PT-MIPMME) has been used for the selective extraction of sulfamethoxazole in milk, achieving high recoveries and low standard deviations [40]. This type of extraction was used also for the selective extraction of diferonocazole in tap water and grape juice using PT-MIPMME [46]. In a similar approach, the metallic needle of the pinhead of a syringe can be replaced by a polymer monolith and coupled to a syringe infusion pump.