Evaluation of the Origins of the Selectivity of Polymers Imprinted with a HIV Protease Inhibitor using Infrared Spectroscopy and High Performance Liquid Chromatography

Seton Hall University, South Orange, New Jersey, United States
Enantiomer A Journal of Stereochemistry 03/2002; 7(2-3):139-48. DOI: 10.1080/10242430212193
Source: PubMed


This work investigates the origins of enantioselectivity of polymers imprinted with the HIV protease inhibitor, Indinavir. For the preparation of imprints of the drug, the critical interactions between the functional monomer, methacrylic acid, and Indinavir were characterized by infrared (IR) spectroscopy to explore the optimum functional monomer concentration for the polymerization. It was shown that a polymer with high selectivity and minimum non-selective binding for Indinavir was obtained when prepared with enough functional monomer to hydrogen bond with all of the functional groups of the drug without using an excess of monomer. This observation is explained in terms of a balance that is achieved in the monomer-template equilibrium during the polymerization that yields a polymer with highly selective sites and minimal non-selective sites. This paper further demonstrates that IR spectroscopy can be a valuable tool in the design and syntheses of molecular imprinted polymers.

Download full-text


Available from: Nelu Grinberg, Jan 26, 2015
  • [Show abstract] [Hide abstract]
    ABSTRACT: Molecular imprinting, a technique that allows for preparation of adsorbents with sites tailored for recognition of a particular molecule, continues to grow because it holds promise for several areas including separations. A key fundamental aspect in forming a molecular imprinted polymer (MIP) is the ability to optimize the amount of functional monomer relative to template used for the polymerization. In this paper, isothermal titration calorimetry (ITC) was used to predict the optimum functional monomer concentration for preparing an MIP for the drug, cinchonidine. Calorimetric titrations of cinchonidine with the functional monomer, methacrylic acid, suggested that a methacrylic acid–cinchonidine hydrogen bonded complex of minimum energy exists for solutions of 4:1 mol/mol of the monomer relative to the template. When this ratio of functional monomer to template was utilized for the MIP synthesis, the resulting polymer displayed significantly better selectivity for cinchonidine than polymers prepared with lesser or greater amounts of methacrylic acid. This observation is explained in terms of a balance that was achieved in the monomer–template equilibrium during the polymerization. This balance maximizes the favorable hydrogen bonding interactions with the template during the polymerization that yields the selective sites, but minimizes the use of excess monomer, which leads to non‐selective sites on the polymer. The results within suggest that ITC can be a valuable tool in the syntheses of MIPs.
    No preview · Article · Jan 2005 · Journal of Liquid Chromatography & Related Technologies
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: Over 1450 references to original papers, reviews and monographs have herein been collected to document the development of molecular imprinting science and technology from the serendipitous discovery of Polyakov in 1931 to recent attempts to implement and understand the principles underlying the technique and its use in a range of application areas. In the presentation of the assembled references, a section presenting reviews and monographs covering the area is followed by papers dealing with fundamental aspects of molecular imprinting and the development of novel polymer formats. Thereafter, literature describing attempts to apply these polymeric materials to a range of application areas is presented.
    Full-text · Article · Mar 2006 · Journal of Molecular Recognition
  • [Show abstract] [Hide abstract]
    ABSTRACT: A molecularly imprinted polymer (MIP) has been prepared using levonorgestrel (LEV) as template. The polymer was synthesised in a non-covalent approach using methacrylic acid (MAA) as functional monomer and ethylene glycol dimethacrylate (EGDMA) as cross-linking monomer via a free radical polymerization. An equivalent blank polymer was also synthesised in the absence of the template compound. Batch adsorption experiments were used to evaluate the binding affinity of the imprinted polymer. After packing MIP into a stainless steel column (150 mm x 4.6 mm i.d.), retention and elution of the template and related compounds were evaluated by high-performance liquid chromatography (HPLC). This LEV imprinted polymer was further applied for selective solid phase extraction (SPE) of LEV from human serum. It was confirmed that the binding ability of the prepared MIP for LEV was essentially sufficient in the presence of other compounds coexisting in serum sample. Therefore, as a selective and efficient solid phase material, LEV imprinted polymer has a high potential application in analysis of this steroidal hormone in clinical purposes.
    No preview · Article · Jun 2008 · Journal of Chromatography B
Show more