Molecularly imprinted polymers enantiomers

Molecular imprinted polymers MIPs exhibit predetermined enan-tioselectivity for a specific chiral molecnle, which is nsed as the chiral template dnring the imprinting process. Most MIPs are obtained by copolymerization from a mixture consisting of a fnnctional mono-nnsatn-rated (vinylic, acrylic, methacrylic) monomer, a di- or tri-nnsatnrated cross-linker (vinylic, acrylic, methacrylic), a chiral template (print molecnle) and a porogenic solvent to create a three-dimensional network. When removing the print molecnle, chiral cavities are released within the polymer network. The MIP will memorize the steric and functional binding featnres of the template molecnle. Therefore, inclusion of the enantiomers into the asymmetric cavities of this network can be assumed as... 

Figure 15.4 Fiber optic measurements of the dansyl-L-Phe-OH molecular imprinted polymers (l-MIP) in the presence of increasing amounts of enantiomers. ( ) Dansyl-L-Phe-OH and ( ) dansyl-D-Phe-OH. Reprinted from Kriz et al. (1995). Copyright 1995 American Chemical Society.

Molecularly imprinted polymers (MIPs) allow for predetermined selectivity of enantiomers. MIPs are prepared by polymerizing a mixture of functional mono-mer(s) and cross-linking monomer in the presence of a template molecule. The template molecule remains in a pocket by its interaction with a functional monomer through hydrogen bonding. This allows the MIP to be found at the surface of the polymer. When polymerization is complete and the template molecule is removed, the polymer remembers the template molecule. 

Molecularly imprinted polymer (MIP) type CSPs. Driven by the concept of preparing highly stereoselective synthetic receptors to be used as chiral SOs for the separation of enantiomers. MIP type CSPs have been prepared. These exhibit predetermined... 

Hart BR, Rush DJ, Shea KJ (2000) Discrimination between enantiomers of structurally related molecules Separation of benzodiazepines by molecularly imprinted polymers. J Am Chem Soc 122 460... 

Fig. 7.13 (A) Chemical structures of nategli-nide and chemically/diastereomerically related compounds. (B) Separation of nateglinide and related compounds on molecularly imprinted polymers and non-imprinted control polymers. (a) Separation of nateglinide and L-enantiomer on the monolithic MIP.

Yin, J.,Yang, G., Chen,Y. Rapid and efficient chiral separation of nateglinide and its L-enantiomer on monolithic molecularly imprinted polymers,/. Chromatogr. 

Allender CJ, Brain KR, Heard CM (1997) Binding cross-reactivity of Boc-phenyl-alanine enantiomers on molecularly imprinted polymers. Chirality 9(3) 233-237... 

The stereoselective release behaviors of low-swelling molecularly imprinted polymer bead matrices in pressed-coat tablets were studied using either R- or S-propranolol selective MIPs. The in vitro release profiles of the low-swelling matrices showed a difference in the release of enantiomers, in that the nontemplate isomer was released faster than the template isomer. However, in the last phase of dissolution this difference was reduced and later reversed [64]. Stereoselectivity of release profiles for propranolol enantiomers were identified in MIP synthetic membranes from tablet formulations with significant differences between enantiomers [65]. Release of the enantiomer used as the print was always faster than the... 

Legge, C., and Turner, A. P. F. (2001). Recognition of ephedrine enantiomers by molecularly imprinted polymers designed using a computational approach, 126,1826-1830. 

Kempe, M. (2001). Molecularly imprinted polymers in enantiomer separations. In... 

Lin, J.M. Nakagama, T. Uchiyama, K. Hobo, T. Capillary electrochromatographic separation of amino acid enantiomers using on-column prepared molecularly imprinted polymer. J. Pharmaceut. Biomed. Anal. 1997,15, 1351-1358. 

Allender, C.J. Brain, K.R. Heard, C.M. Binding cross-reactivity d Boc-phenylalanine enantiomers on molecularly imprinted polymers. Chirality 1997, 9, 233-237. 

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