MIPs formats

The problems with the wide, tailing peaks have prevented the widespread use of MIPs in HPLC. Recently, however, a number of studies have shown that MIPs can still have a place in the inventory of the chromatographic lab. While the more important MIP format for handling real samples appears to be SPE, use of MIP HPLC columns can also be useful. 

Analyte MIP format Recognition Protocol Sample Sample modification Washing Elution Detection Referenct... 

The non-covalent imprinting process is perhaps best considered in terms of the sequential nature of the individual steps involved, which are summarised in Figure 6.8. The key to MIP formation is a series of regiospecific non-covalent interactions between the template and functional monomers to form a pre-polymerisation complex in the liquid phase. 

The field of sustainable polymers is budding and growing at an unrivaled rate. Molecularly imprinted polymers (MIPs) are the polymer networks endowed with the ability to recognize specific molecules and have an enormous potential for the variety of applications. A perspective is offered in this chapter for the computational modeling-based rational design of MIPs for pharmaceuticals and preparation of different MIPs formats using various polymerization methods. The versatility of application of MIPs in pharmaceutical industries is also emphasized. 

The development of MIPs with a well-defined size and shape is very important for extending the fundamental understanding of MIP formation and recognition by MIPs as well as the practical applications of MIPs. The controlled geometry can help to reduce the problems encountered due to the heterogeneity of MIP binding sites including their uneven distribution in conventional cross-linked bulk MIPs. 

MIAs have been developed for an expanding range of small molecules of medical and environmental interest. Rapid advances are being made in terms of new MIP formats (for easier handling or compatibility with ubiquitous instrumentation, e.g., microplates) and new assay formats replacing radiolabels with fluorophores, electroactive groups, and enzyme labels. In many cases, studies have been limited to proof of principle and it is expected that there will be more emphasis on demonstrating complete analytical procedures based on MIA as the technique becomes more widely accepted. 

The binding sites in these materials rely on noncovalent entanglement of polymer chains which exist as long as the membrane is exposed to a nonsolvent. Thus, the memory effects can be erased by solvent exposure and the method hence suffers from a limited robustness. Instead of this one-pot approach, composite membranes are growing in importance. Here the MIP formation is decoupled from the phase inversion process or technique to form a membrane support of choice. This support can then be used for grafting MIPS either in the film format or by attaching preformed MIP particles. " ... 

Methyl-l-methoxyethyl Ether (MIP-OR) ROC(OCH3)(CH3)2 (Chart 1) Formation... 

Oba Y, Lee JW, Ehrlich LA, et al. MIP-lalpha utilizes both CCR1 and CCR5 to induce osteoclast formation and increase adhesion of myeloma cells to marrow stromal cells. Exp Hematol 2005 33(3) 272-278. 

The improvement of enzyme like MIP is currently another area of intense research. Beside the use of the MIP themselves as catalysts, they may also be applied as enhancer of product yield in bio-transformation processes. In an exemplary condensation of Z-L-aspartic acid with L-phenylalanine methyl ester to Z-aspartame, the enzyme thermolysin was used as catalyst. In order to shift the equilibrium towards product formation, a product imprinted MIP was added. By adsorbing specifically the freshly generated product from the reaction mixture, the MIP helped to increase product formation by 40% [130]. MIP can also be used to support a physical process. Copolymers of 6-methacrylamidohexanoic acid and DVB generated in the presence of calcite were investigated with respect to promotion of the nucleation of calcite. Figure 19 (left) shows the polymer surface with imprints from the calcite crystals. When employing these polymers in an aqueous solution of Ca2+ and CO2 the enhanced formation of rhombohedral calcite crystals was observed see Fig. 19 (right) [131]. 

One direct approach to the separation of chiral compounds is called molecular imprint polymers (MIPs) that involves the formation of a three-dimensional cavity with the shape and electronic features that are complementary to the imprinted or target molecule. 

While MIPs are part of the current nanorevolution, its roots are found in Pauling s theory of antibody formation. Although the particulars were wrong, the general concept is good. 

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