## 5 Chemistry of Polymer Rods
### Synthesis of Molecularly Imprinted Monoliths  
Molecular imprinting is a useful technology to create recognition sites in a macromolecular matrix using a template molecule [107]. The molecular imprinting technique needs a synthetically prepared polymer matrix apt to form cavities sculpted around the template molecules of the same kind [98]. Molecularly imprinted polymers (MIPs) are easy to prepare, stable, inexpensive and capable of molecular recognition. They have been used in various analytical separation domains such as liquid chromatography [109, 110], capillary electrophoresis [111, 112] or sensors [113, 114], however, the most intensively studied application is that in solid-phase extraction (SPE) media [115, 116, 117]. Therefore, MIPs can be considered as artificial affinity media. _In situ_ polymerization is a very simple and easy method for preparing MIPs for HPLC or SPE separation. In a typical process, the reaction mixture containing the molecule (mold or template), functional monomers, a high concentration of cross-linking agents, porogenic agents and initiators are poured into a stainless-steel tube, sealed at one end, and degassed ultrasonically. Then, the other end is sealed and the polymerization reaction is allowed to process by heating. Once polymerization occurs, the molecule used as mold is removed by washing from the polymeric structure, remaining \"_printed_\" with the shape of the template molecule. After the removal of the template, the column of MIP monolith can be connected directly to the HPLC system for online SPE or analysis of target molecules [118]. Recently, some efforts have been made to prepare monolithic MIPs in molds, e.g. capillaries, since no crushing, sieving and packing are necessary [119]. [PERSON] and coworkers [120] prepared a MIP monolith by _in situ_ polymerization using Sty, GMA and MAA as monomers, DVB and triallyl isocyanurate as cross-linking agents, and a ceramide as template molecule. The results showed that using ceramide as template molecule significantly affected the pore structure and pore distribution of the monolith, and greatly improved the retention of ceramide and its analogues used in cosmetics as well. This indicated the potential of ceramide imprinted monolith synthesized in the online SPE of ceramides from yeast. [PERSON] _et al._[121] studied and assessed the Fe(III)-imprinted poly(HEMA-_N_-methacryloyl-(_L_) cysteine methyl ester) monolith for its capability to remove Fe(III) in vitro from human plasma with \(\beta\) thalassemia. [PERSON] and coworker [122] reported the preparation of novel monolithic columns with porosity determined by spherical particles of silica. This approach erradicated one of the variablesinvolved in the design of polymer composition: the need for a porogenic solvent. In addition, altering the surface characteristics of the templating beads influenced the composition of the finished monolith surface. For example, the results demonstrated that octadecyl modified silica particles interacted with the hydrophobic moieties of monomers before the initiation of polymerization, thus specifing their orientation in the resulting polymer. MIPs present the ability to selectively discriminate between very similar molecules, which can be applied in the resolution of racemates and in selective catalytic processes. Sinomenine (SIN), an alkaloid with analgesic and antiinflammatory effects, was used as template for the synthesis of an imprinted polymer with specific recognition ability for SIN. It was prepared by _in situ_ molecularly imprinted technique by [PERSON] _et al._[123]. This study has shown that SIN-imprinted copolymers of poly(MAA-co-EGDMA) provide efficient extraction of SIN from herb matrices and rabbit blood. MIPs were used with poly(acrylic acid-co-EGDMA) [poly(AAc-co-EGDMA)] rods to resolve positional isomers of different diamine naphtalenes and enantiomers of anilides of the phenylalanine [124]. [PERSON] _et al._ used the same support for the resolution of various alkaloids of cinchona [125].