Chromatography imprinted chiral phases

Sellergren B. Imprinted chiral stationary phases in high-performance liquid chromatography. J Chromatogr A 2001a 906 227-252. 

Chromatography. Chromatography (HPLC, GC, and TLC) is commonly used in characterization of chiral drugs and has consequently been used in the evaluation of chiral excipient-drug interactions. Many authors have used HPLC to study stereoselectivity between chiral excipients and drugs [3,8,9,40-42]. The columns used in these studies range form octa-desylsilane to chiral selectors such as Chiral AG and molecularly imprinted stationary phases. 

Shea, K.J. Molecular imprinting of synthetic network polymers the de novo synthesis of macromolecular binding and catalytic sites. Trends. Polym. Sci. 1994, 2, 166-173. Sellergren, B. Imprinted chiral stationary phases in high-performance liquid chromatography. J. Chromatogr. A 2001, 906, 227-252. 

Suedee, R. et al.. Chiral determination of various adrenergic drugs by thin-layer chromatography using molecularly imprinted chiral stationary phases prepared with a-agonists. Analyst, 124, 1003,1999. 

B. Sellergren, Enantiomer separation using tailor-made phases prepared by molecular imprinting in A practical approach to chiral separations by liquid chromatography, G. Subramanian, VCH, Weinheim (1994) Chapter 4. 

Beside the use of MIPs in conventional HPLC, Mi-polymers may also be established in supercritical fluid chromatography, which is characterized by faster equilibration times combined with the use of the environmental friendly C02 as mobile phase. Although preliminary results show relatively broad peaks, chiral separation could be performed based on polymers imprinted with an enantiomer. However, the long-term stability of the photochemically generated polymers seems to be a problem [89]. 

The most popular and commonly used chiral stationary phases (CSPs) are polysaccharides, cyclodextrins, macrocyclic glycopeptide antibiotics, Pirkle types, proteins, ligand exchangers, and crown ether based. The art of the chiral resolution on these CSPs has been discussed in detail in Chapters 2-8, respectively. Apart from these CSPs, the chiral resolutions of some racemic compounds have also been reported on other CSPs containing different chiral molecules and polymers. These other types of CSP are based on the use of chiral molecules such as alkaloids, amides, amines, acids, and synthetic polymers. These CSPs have proved to be very useful for the chiral resolutions due to some specific requirements. Moreover, the chiral resolution can be predicted on the CSPs obtained by the molecular imprinted techniques. The chiral resolution on these miscellaneous CSPs using liquid chromatography is discussed in this chapter. 

Most progress in the methods and usage of functional monomers for imprinting has been made in the field of chromatography. Recent analytical applications in the liquid phase often involve chiral separation problems (see Chapter 17). Non-cova-lently imprinted polymers offer suitable solutions, as imprinted polymers with... 

Imprinted materials can be used as stationary phase in affinity chromatography, especially for the separation of enantiomers. Compared to standard chiral stationary phases, these materials present the advantage of being synthesised to order for a given enantiomerically pure molecule. These chromatographic materials have allowed the separation of numerous compounds such as naprox-ene (anti-inflammatory) [139], timolol (beta-blocker) [50] and nicotine [140]. 

Table 3 Examples of Molecular Imprinted Polymers Used as Stationary Phases in Chiral Chromatography...

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