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Sobiech M, Bujak P, Luliński P, Pron A. Semiconductor nanocrystal-polymer hybrid nanomaterials and their application in molecular imprinting. NANOSCALE 2019; 11:12030-12074. [PMID: 31204762 DOI: 10.1039/c9nr02585e] [Citation(s) in RCA: 29] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/13/2023]
Abstract
Quantum dots (QDs) are attractive semiconductor fluorescent nanomaterials with remarkable optical and electrical properties. The broad absorption spectra and high stability of QD transducers are advantageous for sensing and bioimaging. Molecular imprinting is a technique for manufacturing synthetic polymeric materials with a high recognition ability towards a target analyte. The high selectivity of the molecularly imprinted polymers (MIPs) is a result of the fabrication process based on the template-tailored polymerization of functional monomers. The three-dimensional cavities formed in the polymer network can serve as the recognition elements of sensors because of their specificity and stability. Appending specific molecularly imprinted layers to QDs is a promising strategy to enhance the stability, sensitivity, and selective fluorescence response of the resulting sensors. By merging the benefits of MIPs and QDs, inventive optical sensors are constructed. In this review, the recent synthetic strategies used for the fabrication of QD nanocrystals emphasizing various approaches to effective functionalization in aqueous environments are discussed followed by a detailed presentation of current advances in QD conjugated MIPs (MIP-QDs). Frontiers in manufacturing of specific imprinted layers of these nanomaterials are presented and factors affecting the specific behaviour of an MIP shell are identified. Finally, current limitations of MIP-QDs are defined and prospects are outlined to amplify the capability of MIP-QDs in future sensing.
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Affiliation(s)
- Monika Sobiech
- Department of Organic Chemistry, Faculty of Pharmacy, Medical University of Warsaw, Banacha 1, 02-097 Warsaw, Poland
| | - Piotr Bujak
- Warsaw University of Technology, Faculty of Chemistry, Noakowskiego 3, 00-664 Warsaw, Poland.
| | - Piotr Luliński
- Department of Organic Chemistry, Faculty of Pharmacy, Medical University of Warsaw, Banacha 1, 02-097 Warsaw, Poland
| | - Adam Pron
- Warsaw University of Technology, Faculty of Chemistry, Noakowskiego 3, 00-664 Warsaw, Poland.
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Characterization of the Binding Properties of Molecularly Imprinted Polymers. ADVANCES IN BIOCHEMICAL ENGINEERING/BIOTECHNOLOGY 2015; 150:51-93. [PMID: 25796622 DOI: 10.1007/10_2015_316] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
The defining characteristic of the binding sites of any particular molecularly imprinted material is heterogeneity: that is, they are not all identical. Nonetheless, it is useful to study their fundamental binding properties, and to obtain average properties. In particular, it has been instructive to compare the binding properties of imprinted and non-imprinted materials. This chapter begins by considering the origins of this site heterogeneity. Next, the properties of interest of imprinted binding sites are described in brief: affinity, selectivity, and kinetics. The binding/adsorption isotherm, the graph of concentration of analyte bound to a MIP versus concentration of free analyte at equilibrium, over a range of total concentrations, is described in some detail. Following this, the techniques for studying the imprinted sites are described (batch-binding assays, radioligand binding assays, zonal chromatography, frontal chromatography, calorimetry, and others). Thereafter, the parameters that influence affinity, selectivity and kinetics are discussed (solvent, modifiers of organic solvents, pH of aqueous solvents, temperature). Finally, mathematical attempts to fit the adsorption isotherms for imprinted materials, so as to obtain information about the range of binding affinities characterizing the imprinted sites, are summarized.
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Ali I, Al-Othman ZA, Al-Warthan A, Asnin L, Chudinov A. Advances in chiral separations of small peptides by capillary electrophoresis and chromatography. J Sep Sci 2014; 37:2447-66. [DOI: 10.1002/jssc.201400587] [Citation(s) in RCA: 101] [Impact Index Per Article: 10.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/28/2014] [Revised: 06/26/2014] [Accepted: 06/27/2014] [Indexed: 01/27/2023]
Affiliation(s)
- Imran Ali
- Department of Chemistry, Jamia Millia Islamia (Central University); New Delhi India
| | - Zeid A. Al-Othman
- Department of Chemistry, College of Science; King Saud University; Riyadh Kingdom of Saudi Arabia
| | - Abdulrahman Al-Warthan
- Department of Chemistry, College of Science; King Saud University; Riyadh Kingdom of Saudi Arabia
| | - Leonid Asnin
- Perm National Research Polytechnic University; Perm Russia
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Song D, Zhang Y, Geer MF, Shimizu KD. Characterization of molecularly imprinted polymers using a new polar solvent titration method. J Mol Recognit 2014; 27:448-57. [DOI: 10.1002/jmr.2365] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/27/2013] [Revised: 01/15/2014] [Accepted: 01/28/2014] [Indexed: 11/08/2022]
Affiliation(s)
- Di Song
- Department of Chemistry and Biochemistry; University of South Carolina; Columbia SC 29208 USA
| | - Yagang Zhang
- Department of Chemistry and Biochemistry; University of South Carolina; Columbia SC 29208 USA
| | - Michael F. Geer
- Department of Chemistry and Biochemistry; University of South Carolina; Columbia SC 29208 USA
| | - Ken D. Shimizu
- Department of Chemistry and Biochemistry; University of South Carolina; Columbia SC 29208 USA
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Adsorption models in chiral chromatography. J Chromatogr A 2012; 1269:3-25. [DOI: 10.1016/j.chroma.2012.08.096] [Citation(s) in RCA: 36] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/04/2012] [Revised: 08/26/2012] [Accepted: 08/28/2012] [Indexed: 12/20/2022]
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Ahmadi F, Rezaei H, Tahvilian R. Computational-aided design of molecularly imprinted polymer for selective extraction of methadone from plasma and saliva and determination by gas chromatography. J Chromatogr A 2012; 1270:9-19. [DOI: 10.1016/j.chroma.2012.10.038] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/10/2012] [Revised: 09/30/2012] [Accepted: 10/17/2012] [Indexed: 10/27/2022]
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Experimental and theoretical studies on the enantioselectivity of molecularly imprinted polymers prepared with a chiral functional monomer. J Chromatogr A 2012; 1266:24-33. [DOI: 10.1016/j.chroma.2012.09.042] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/23/2012] [Revised: 08/19/2012] [Accepted: 09/14/2012] [Indexed: 11/22/2022]
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Vasapollo G, Sole RD, Mergola L, Lazzoi MR, Scardino A, Scorrano S, Mele G. Molecularly imprinted polymers: present and future prospective. Int J Mol Sci 2011; 12:5908-45. [PMID: 22016636 PMCID: PMC3189760 DOI: 10.3390/ijms12095908] [Citation(s) in RCA: 548] [Impact Index Per Article: 42.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/07/2011] [Revised: 08/03/2011] [Accepted: 08/17/2011] [Indexed: 11/16/2022] Open
Abstract
Molecular Imprinting Technology (MIT) is a technique to design artificial receptors with a predetermined selectivity and specificity for a given analyte, which can be used as ideal materials in various application fields. Molecularly Imprinted Polymers (MIPs), the polymeric matrices obtained using the imprinting technology, are robust molecular recognition elements able to mimic natural recognition entities, such as antibodies and biological receptors, useful to separate and analyze complicated samples such as biological fluids and environmental samples. The scope of this review is to provide a general overview on MIPs field discussing first general aspects in MIP preparation and then dealing with various application aspects. This review aims to outline the molecularly imprinted process and present a summary of principal application fields of molecularly imprinted polymers, focusing on chemical sensing, separation science, drug delivery and catalysis. Some significant aspects about preparation and application of the molecular imprinting polymers with examples taken from the recent literature will be discussed. Theoretical and experimental parameters for MIPs design in terms of the interaction between template and polymer functionalities will be considered and synthesis methods for the improvement of MIP recognition properties will also be presented.
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Affiliation(s)
- Giuseppe Vasapollo
- Department of Engineering of Innovation, University of Salento, via per Arnesano km 1, Lecce 73100, Italy; E-Mails: (R.D.S.); (L.M.); (M.R.L.); (A.S.); (S.S.); (G.M.)
| | - Roberta Del Sole
- Department of Engineering of Innovation, University of Salento, via per Arnesano km 1, Lecce 73100, Italy; E-Mails: (R.D.S.); (L.M.); (M.R.L.); (A.S.); (S.S.); (G.M.)
| | - Lucia Mergola
- Department of Engineering of Innovation, University of Salento, via per Arnesano km 1, Lecce 73100, Italy; E-Mails: (R.D.S.); (L.M.); (M.R.L.); (A.S.); (S.S.); (G.M.)
| | - Maria Rosaria Lazzoi
- Department of Engineering of Innovation, University of Salento, via per Arnesano km 1, Lecce 73100, Italy; E-Mails: (R.D.S.); (L.M.); (M.R.L.); (A.S.); (S.S.); (G.M.)
| | - Anna Scardino
- Department of Engineering of Innovation, University of Salento, via per Arnesano km 1, Lecce 73100, Italy; E-Mails: (R.D.S.); (L.M.); (M.R.L.); (A.S.); (S.S.); (G.M.)
| | - Sonia Scorrano
- Department of Engineering of Innovation, University of Salento, via per Arnesano km 1, Lecce 73100, Italy; E-Mails: (R.D.S.); (L.M.); (M.R.L.); (A.S.); (S.S.); (G.M.)
| | - Giuseppe Mele
- Department of Engineering of Innovation, University of Salento, via per Arnesano km 1, Lecce 73100, Italy; E-Mails: (R.D.S.); (L.M.); (M.R.L.); (A.S.); (S.S.); (G.M.)
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Affiliation(s)
- Benjamin S. Murray
- Chemical Nanoscience Laboratory, School of Chemistry, Bedson Building, Newcastle University, Newcastle upon Tyne NE1 7RU, United Kingdom
| | - David A. Fulton
- Chemical Nanoscience Laboratory, School of Chemistry, Bedson Building, Newcastle University, Newcastle upon Tyne NE1 7RU, United Kingdom
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Xu ZX, Gao HJ, Zhang LM, Chen XQ, Qiao XG. The biomimetic immunoassay based on molecularly imprinted polymer: a comprehensive review of recent progress and future prospects. J Food Sci 2011; 76:R69-75. [PMID: 21535786 DOI: 10.1111/j.1750-3841.2010.02020.x] [Citation(s) in RCA: 64] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
UNLABELLED Immunoassay, based on a selective affinity of the biological antibody for its antigen, is one of the most usual analytical methods in food safety and environmental chemistry. However, it presents several drawbacks because of the nature of the antibody. Molecular imprinting technique, due to its high selectivity and stability, ease of preparation and low cost, has shown great potential in producing artificial antibodies in biomimetic immunoassays. This article focuses on the recent states, advantages, current problems and outlooks of molecularly imprinted radio, fluoro, enzyme-linked and chemiluminescent immunoassays, and biomimetic immunosensor, with special emphasis on the challenges in developing biomimetic enzyme-linked immunosorbent assays (BELISAs). The biomimetic immunoassay method will provide an important new analysis platform in food safety, although the sensitivity and specificity is relatively low. PRACTICAL APPLICATION As a new simple analysis method, the biomimetic immunoassay has attractive prospect, although some limitations were existed in real-sample assay. In this critical review, some promising solutions for overcoming its drawbacks were put forward, which may promote the more quick development and extensive application of this method in food safety.
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Affiliation(s)
- Z X Xu
- College of Food Science and Engineering, Shandong Agricultural Univ, Taian 271018, China
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Njikang G, Liu G, Hong L. Chiral imprinting of diblock copolymer single-chain particles. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2011; 27:7176-7184. [PMID: 21528850 DOI: 10.1021/la2006887] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/30/2023]
Abstract
This Article reports the molecular imprinting of polymer single-chain particles that have a radius ∼3.7 nm. For this, the template L-phenylalanine anilide or L-ΦAA and a diblock copolymer PtBA-b-P(CEMA-r-CA) were used. Here, PtBA denotes poly(tert-butyl acrylate), and P(CEMA-r-CA) denotes a random block consisting of cinnamoyloxyethyl methacrylate (CEMA) and carboxyl-bearing (CA) units. In CHCl(3)/cyclohexane (CHX) with 64 vol % of CHX or at f(CHX) = 64%, a block-selective solvent for PtBA, PtBA-b-P(CEMA-r-CA) formed spherical micelles. The core consisted of the insoluble P(CEMA-r-CA) block and L-ΦAA, which complexed with the CA groups. Pumping slowly this micellar solution into stirred CHCl(3)/(CHX) at f(CHX) = 64% triggered micelle dissociation into single-chain micelles, which comprised presumably a solubilized PtBA tail and a collapsed P(CEMA-r-CA)/L-ΦAA head. Because the solvent reservoir was under constant UV irradiation, the photo-cross-linkable units in the P(CEMA-r-CA) head cross-linked, and the single-chain micelles were converted into cross-linked single-chain micelles or tadpoles. Synchronizing the micelle addition and photoreaction rates allowed the preparation, from this protocol, of essentially pure tadpoles at high final polymer concentrations. Imprinted tadpoles were procured after L-ΦAA was extracted from the tadpole heads. Under optimized conditions, the produced imprinted tadpoles had exceptionally high binding capacity and high selectivity for L-ΦAA. In addition, the rates of L-ΦAA release from and rebinding by the particles were high.
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Affiliation(s)
- Gabriel Njikang
- Department of Chemistry, Queen's University, 90 Bader Lane, Kingston, Ontario K7L 3N6, Canada
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Baggiani C, Baravalle P, Giovannoli C, Anfossi L, Passini C, Giraudi G. Binding behaviour of molecularly imprinted polymers prepared by a hierarchical approach in mesoporous silica beads of varying porosity. J Chromatogr A 2011; 1218:1828-34. [DOI: 10.1016/j.chroma.2011.02.003] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/06/2010] [Revised: 12/28/2010] [Accepted: 02/02/2011] [Indexed: 10/18/2022]
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Abstract
ABSTRACTA new mechanistic diagram describing the non-covalent molecular imprinting process is put forth in the text. A significant consequence of the new mechanistic picture is that the pre-polymer complex structure does not necessarily reflect the structure of the final binding sites in the polymer. Two independent studies are presented in combined form that support the suggested changes to the mechanistic diagram. In the first study, the maximum number of functional groups surrounding the template molecule in solution are shown to be less than the average number of functional groups in the binding sites of the polymers. In the second study, shape selectivity is shown to be an important contributor to molecular recognition by the imprinted polymers; which is significant because contributions of shape cannot be predicted by the solution phase pre-polymer complex.
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Kumar KV, Monteiro de Castro M, Martinez-Escandell M, Molina-Sabio M, Rodriguez-Reinoso F. A site energy distribution function from Toth isotherm for adsorption of gases on heterogeneous surfaces. Phys Chem Chem Phys 2011; 13:5753-9. [DOI: 10.1039/c0cp00902d] [Citation(s) in RCA: 49] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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Zhang Y, Song D, Brown JC, Shimizu KD. Suppression of background sites in molecularly imprinted polymersviaurea-urea monomer aggregation. Org Biomol Chem 2011; 9:120-6. [DOI: 10.1039/c0ob00637h] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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Vasanth Kumar K, de Castro MM, Martinez-Escandell M, Molina-Sabio M, Silvestre-Albero J, Rodriguez-Reinoso F. A continuous site energy distribution function from Redlich–Peterson isotherm for adsorption on heterogeneous surfaces. Chem Phys Lett 2010. [DOI: 10.1016/j.cplett.2010.04.044] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
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Holland N, Frisby J, Owens E, Hughes H, Duggan P, McLoughlin P. The influence of polymer morphology on the performance of molecularly imprinted polymers. POLYMER 2010. [DOI: 10.1016/j.polymer.2009.10.035] [Citation(s) in RCA: 43] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
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Karlsson BCG, O’Mahony J, Karlsson JG, Bengtsson H, Eriksson LA, Nicholls IA. Structure and Dynamics of Monomer−Template Complexation: An Explanation for Molecularly Imprinted Polymer Recognition Site Heterogeneity. J Am Chem Soc 2009; 131:13297-304. [DOI: 10.1021/ja902087t] [Citation(s) in RCA: 96] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Affiliation(s)
- Björn C. G. Karlsson
- Bioorganic and Biophysical Chemistry Laboratory, School of Pure and Applied Natural Sciences, University of Kalmar, SE-391 82 Kalmar, Sweden and School of Chemistry, National University of Ireland — Galway, Galway, Ireland
| | - John O’Mahony
- Bioorganic and Biophysical Chemistry Laboratory, School of Pure and Applied Natural Sciences, University of Kalmar, SE-391 82 Kalmar, Sweden and School of Chemistry, National University of Ireland — Galway, Galway, Ireland
| | - Jesper G. Karlsson
- Bioorganic and Biophysical Chemistry Laboratory, School of Pure and Applied Natural Sciences, University of Kalmar, SE-391 82 Kalmar, Sweden and School of Chemistry, National University of Ireland — Galway, Galway, Ireland
| | - Helen Bengtsson
- Bioorganic and Biophysical Chemistry Laboratory, School of Pure and Applied Natural Sciences, University of Kalmar, SE-391 82 Kalmar, Sweden and School of Chemistry, National University of Ireland — Galway, Galway, Ireland
| | - Leif A. Eriksson
- Bioorganic and Biophysical Chemistry Laboratory, School of Pure and Applied Natural Sciences, University of Kalmar, SE-391 82 Kalmar, Sweden and School of Chemistry, National University of Ireland — Galway, Galway, Ireland
| | - Ian A. Nicholls
- Bioorganic and Biophysical Chemistry Laboratory, School of Pure and Applied Natural Sciences, University of Kalmar, SE-391 82 Kalmar, Sweden and School of Chemistry, National University of Ireland — Galway, Galway, Ireland
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Zaidi SA, Cheong WJ. Preparation of an open-tubular capillary column with a monolithic layer of S-ketoprofen imprinted and 4-styrenesulfonic acid incorporated polymer and its enhanced chiral separation performance in capillary electrochromatography. J Chromatogr A 2009; 1216:2947-52. [DOI: 10.1016/j.chroma.2008.08.015] [Citation(s) in RCA: 57] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/10/2008] [Revised: 08/05/2008] [Accepted: 08/08/2008] [Indexed: 10/21/2022]
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Szabelski P, Kaczmarski K. Phenomenological modeling of separation of enantiomers by nonlinear chromatography. ACTA CHROMATOGR 2008. [DOI: 10.1556/achrom.20.2008.4.1] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
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Wei S, Mizaikoff B. Binding site characteristics of 17β-estradiol imprinted polymers. Biosens Bioelectron 2007; 23:201-9. [PMID: 17540554 DOI: 10.1016/j.bios.2007.03.031] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/02/2007] [Revised: 03/22/2007] [Accepted: 03/27/2007] [Indexed: 11/25/2022]
Abstract
The variety of applications utilizing molecularly imprinted polymers (MIPs) requires synthetic strategies yielding different MIP formats including films, irregular particles, or spheres, along with precise knowledge on the specific material characteristics, such as binding capacity and binding efficiency of these materials. In response to this demand, MIPs are prepared in different formats by variation of the polymerization methodology. It is commonly agreed that micro- and sub-microspheres are particularly advantageous MIP formats, due to their monodispersity and facile synthesis procedures in contrast to conventional imprinted polymers prepared by bulk polymerization. However, the differences in actual rebinding characteristics of different MIP formats based on molecular interactions under a variety of binding/rebinding conditions have not been studied in detail to date. Consequently, the present work details an analytical strategy generically applicable to MIP systems for rebinding studies including equilibrium binding, non-equilibrium binding, and release experiments enabling more profound understanding on the molecular interactions between the imprinted materials and the template molecules. In this study, three MIP formats were considered for the same template molecule, 17beta-estradiol: irregularly shaped particulate polymers prepared by bulk polymerization and grinding, microspheres, and sub-microspheres. The latter two formats were synthesized via precipitation polymerization using different processing strategies. The morphologies and porosities of the resulting imprinted materials were characterized by scanning electron microscopy (SEM) and Brunauer-Emmett-Teller (BET) analysis, respectively. The obtained results indicate that microspheres prepared by precipitation polymerization provide superior rebinding properties during equilibrium binding in contrast to bulk polymers and sub-microspheres, and that the rebinding properties are different during equilibrium binding versus non-equilibrium binding. The median binding affinity constant determined during non-equilibrium rebinding is higher than the values obtained from equilibrium rebinding. Furthermore, the binding site distribution appears more homogeneous thief derived from non-equilibrium rebinding, as reflected in a heterogeneity index of m=0.725. Moreover, it is hypothesized that the specific interactions between template and monomers are related to the porosity of the imprinted polymers, which implies that the amount of binding sites and the pore sized distribution of the imprinted materials are a critical factor in achieving the desired MIP performance in various analytical applications. The BET results indicate that particles prepared with lower cross-linker-to-template ratio have a reduced surface area. Furthermore, it can be expected that there are less specific binding sites available at particles with reduced surface area and pore volume given similar distribution of the binding sites, as confirmed by the equilibrium binding isotherm studies. The pore size distribution results reveal that control of the pore size in the range of 100-180 A is essential to obtain the desired retention properties and Gaussian peak shape during HPLC analysis of small molecules.
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Affiliation(s)
- Shuting Wei
- School of Chemistry and Biochemistry, Georgia Institute of Technology, Atlanta, GA 30332-0400, USA
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Maier NM, Lindner W. Chiral recognition applications of molecularly imprinted polymers: a critical review. Anal Bioanal Chem 2007; 389:377-97. [PMID: 17632705 DOI: 10.1007/s00216-007-1427-4] [Citation(s) in RCA: 167] [Impact Index Per Article: 9.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/24/2007] [Revised: 06/05/2007] [Accepted: 06/08/2007] [Indexed: 10/23/2022]
Abstract
Molecular imprinting technology offers the unique opportunity to tailor chiral stationary phases with predefined chiral recognition properties by employing the enantiomers of interest as binding-site-forming templates. Added advantages, such as ease of preparation, chemical robustness, low-cost production, and the possibility of shaping molecularly imprinted polymers (MIPs) in various self-supporting formats, render them attractive materials for a broad range of chiral recognition applications. In this review a critical overview on recent developments in the field of MIP-based chiral recognition applications is given, focusing on separation techniques and molecular sensing. Inherent limitations associated with the use of enantioselective MIP materials in high-performance separation techniques are outlined, including binding site heterogeneity and slow mass transfer characteristics. The prospects of MIP materials as versatile recognition elements for the design of enantioselective sensor systems are highlighted.
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Affiliation(s)
- Norbert M Maier
- Department of Analytical Chemistry and Food Chemistry, University of Vienna, Währinger Str. 38, 1090 Vienna, Austria.
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Stephenson CJ, Shimizu KD. Colorimetric and fluorometric molecularly imprinted polymer sensors and binding assays. POLYM INT 2007. [DOI: 10.1002/pi.2206] [Citation(s) in RCA: 56] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
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Diñeiro Y, Menéndez MI, Blanco-López MC, Lobo-Castañón MJ, Miranda-Ordieres AJ, Tuñón-Blanco P. Computational predictions and experimental affinity distributions for a homovanillic acid molecularly imprinted polymer. Biosens Bioelectron 2006; 22:364-71. [PMID: 16766178 DOI: 10.1016/j.bios.2006.03.027] [Citation(s) in RCA: 66] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/23/2005] [Revised: 02/20/2006] [Accepted: 03/02/2006] [Indexed: 11/19/2022]
Abstract
Density Functional Theory calculations have been used to select, among a set of chemicals traditionally used in the formulation of non-covalent molecularly imprinted polymers (MIPs), the best functional monomer and porogenic solvent for the construction of a recognition element for the dopamine metabolite homovanillic acid (HVA). Theoretical predictions were confirmed through batch binding assays and voltammetric detection. The computational method predicts that trifluoromethacrylic acid and toluene are the monomer and solvent rendering the highest stabilization energy for the pre-polymerization adducts. HVA-MIP prepared using this formulation gives rise to a binding isotherm that is accurately modelled by the Freundlich isotherm. The binding properties of this polymer were estimated using affinity distribution analysis. An apparent number of sites of 13 micromol g(-1) with an average affinity constant of 2 x 10(4) M(-1) was obtained in the concentration window studied.
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Affiliation(s)
- Yolanda Diñeiro
- Departamento de Química Física y Analítica, Universidad de Oviedo, Julián Clavería, 8. 33006 Oviedo, Spain
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Kim H, Kaczmarski K, Guiochon G. Isotherm parameters and intraparticle mass transfer kinetics on molecularly imprinted polymers in acetonitrile/buffer mobile phases. Chem Eng Sci 2006. [DOI: 10.1016/j.ces.2006.03.043] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
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Szabelski P, Kaczmarski K. Theoretical investigations of the chromatographic separation of interacting enantiomers. J Chromatogr A 2006; 1113:74-83. [PMID: 16473359 DOI: 10.1016/j.chroma.2006.01.119] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/25/2005] [Revised: 01/25/2006] [Accepted: 01/27/2006] [Indexed: 10/25/2022]
Abstract
Separation of a pair of enantiomers by liquid chromatography is modeled using the equilibrium dispersive (ED) model of chromatography. It is assumed that the chiral stationary phase used for the separation consists of two types of adsorption sites, including chiral selectors linked to the surface and nonselective centers belonging to the achiral matrix. Additionally, intermolecular interactions between adsorbed enantiomers are taken into account. The corresponding equilibrium adsorption isotherms of the enantiomers are derived by means of the mean field approximation (MFA) and used as input data for the ED model. Special attention is paid to the influence of the lateral interactions on the effectiveness of the enantiomer separation. In particular, we examine the effect of the interactions on the shape and relative position of the chromatographic peaks associated with the enantiomers. Furthermore, the influence of the spacer length, which modifies screening of the lateral interactions, on the adsorption process is studied. The obtained results suggest that the lateral interactions combined with the screening effect may cause serious changes in the separation, depending on the nature (attraction or repulsion) and strength of the interactions as well as on the spacer length.
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Affiliation(s)
- Paweł Szabelski
- Department of Theoretical Chemistry, Faculty of Chemistry, Maria Curie-Skłodowska University, Pl. M.C. Skłodowskiej 3, 20-031 Lublin, Poland.
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Garcés JL, Mas F, Puy J. Conditional equilibrium constants in multicomponent heterogeneous adsorption: The conditional affinity spectrum. J Chem Phys 2006; 124:044710. [PMID: 16460203 DOI: 10.1063/1.2162876] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
The concept of conditional stability constant is extended to the competitive binding of small molecules to heterogeneous surfaces or macromolecules via the introduction of the conditional affinity spectrum (CAS). The CAS describes the distribution of effective binding energies experienced by one complexing agent at a fixed concentration of the rest. We show that, when the multicomponent system can be described in terms of an underlying affinity spectrum [integral equation (IE) approach], the system can always be characterized by means of a CAS. The thermodynamic properties of the CAS and its dependence on the concentration of the rest of components are discussed. In the context of metal/proton competition, analytical expressions for the mean (conditional average affinity) and the variance (conditional heterogeneity) of the CAS as functions of pH are reported and their physical interpretation discussed. Furthermore, we show that the dependence of the CAS variance on pH allows for the analytical determination of the correlation coefficient between the binding energies of the metal and the proton. Nonideal competitive adsorption isotherm and Frumkin isotherms are used to illustrate the results of this work. Finally, the possibility of using CAS when the IE approach does not apply (for instance, when multidentate binding is present) is explored.
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Affiliation(s)
- Josep L Garcés
- Research Center of Theoretical Chemistry and Physical-Chemistry Department, Universitat de Barcelona, Marti i Franqués 1, 08028 Barcelona, Spain
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Alexander C, Andersson HS, Andersson LI, Ansell RJ, Kirsch N, Nicholls IA, O'Mahony J, Whitcombe MJ. Molecular imprinting science and technology: a survey of the literature for the years up to and including 2003. J Mol Recognit 2006; 19:106-80. [PMID: 16395662 DOI: 10.1002/jmr.760] [Citation(s) in RCA: 776] [Impact Index Per Article: 43.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/21/2023]
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.
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Affiliation(s)
- Cameron Alexander
- The School of Pharmacy, University of Nottingham, University Park, Nottingham, NG7 2RD, UK
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31
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Kim H, Kaczmarski K, Guiochon G. Mass transfer kinetics on the heterogeneous binding sites of molecularly imprinted polymers. Chem Eng Sci 2005. [DOI: 10.1016/j.ces.2005.04.057] [Citation(s) in RCA: 39] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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Liu ZS, Xu YL, Yan C, Gao RY. Mechanism of molecular recognition on molecular imprinted monolith by capillary electrochromatography. J Chromatogr A 2005; 1087:20-8. [PMID: 16130693 DOI: 10.1016/j.chroma.2005.05.107] [Citation(s) in RCA: 37] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
Abstract
The recognition mechanism of molecularly imprinted polymer (MIP) in capillary electrochromatography (CEC) is complicated since it possesses a hybrid process, which comprises the features of chromatographic retention, electrophoretic migration and molecular imprinting. For an understanding of the molecular recognition of MIP in CEC, a monolithic MIP in a capillary with 1,1'-binaphthyl-2,2'-diamine (BNA) imprinting was prepared by in situ copolymerization of imprinted molecule, methacrylic acid and ethylene glycol dimethacrylate in porogenic solvent, a mixture of toluene-isooctane. Strong recognition ability and high column performance (theory plates was 43,000 plates/m) of BNA were achieved on this monolithic MIP in CEC mode. In addition, BNA and its structural analogue, 1,1'-bi-2, 2'-naphthol, differing in functional groups, were used as model compounds to study imprinting effect on the resultant BNA-imprinted monolithic column, a reference column without imprinting of BNA and a open capillary. The effects of organic modifier concentration, pH value of buffer, salt concentration of buffer and column temperature on the retention and recognition of two compounds were investigated. The results showed that the molecular recognition on MIP monolith in CEC mode mainly derived from imprinting cavities on BNA-imprinted polymer other than chromatographic retention and electrophoretic migration.
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Affiliation(s)
- Zhao-Sheng Liu
- College of Pharmacy, Tianjin Medical University, Tianjin 300070, China
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Rosengren AM, Karlsson JG, Andersson PO, Nicholls IA. Chemometric Models of TemplateMolecularly Imprinted Polymer Binding. Anal Chem 2005; 77:5700-5. [PMID: 16131084 DOI: 10.1021/ac050765v] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
This report provides the first example of the use of chemometrics to describe and predict the extent of template binding to molecularly imprinted polymers. The binding of bupivacaine to imprinted and reference polymers was examined in different solvent mixtures and at various temperatures using equilibrium binding studies. Data were fitted to third-degree equations using partial least-squares regression, resulting in chemometric models describing template binding in this system. The mathematical models demonstrated good correlation (R = 0.72-0.98) and predictive ability (Q = 0.54-0.99), and binding could be described in terms of temperature and dielectric constant. Binding in a nonpolar, aprotic solvent was unaffected by temperature whereas in more polar solvent mixtures temperature had a greater influence. This was explained by changes in the balance between electrostatic and hydrophobic interactions. Moreover, the results demonstrate that temperature has a greater influence on the nonspecific portion of binding, particularly in water-containing solvent mixtures.
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Affiliation(s)
- Annika M Rosengren
- Department of Chemistry and Biomedical Sciences, University of Kalmar, SE-391 82 Kalmar, Sweden
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34
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Comparison of pyrimethanil-imprinted beads and bulk polymer as stationary phase by non-linear chromatography. Anal Chim Acta 2005. [DOI: 10.1016/j.aca.2004.10.088] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
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35
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Lei JD, Tong AJ. Preparation of Z-L-Phe-OH-NBD imprinted microchannel and its molecular recognition study. SPECTROCHIMICA ACTA. PART A, MOLECULAR AND BIOMOLECULAR SPECTROSCOPY 2005; 61:1029-1033. [PMID: 15741098 DOI: 10.1016/j.saa.2004.06.001] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/29/2004] [Accepted: 06/02/2004] [Indexed: 05/24/2023]
Abstract
An integrated microchip was presented for selective recognition of Z-L-Phe-OH-NBD, using molecular imprinting technique. Molecularly imprinted polymer (MIP) were prepared by copolymerization in the presence of template molecule Z-L-Phe-OH-NBD, in which methacrylic acid and 4-vinylpyridine were used as functional monomers and ethylene dimethacrylate used as crosslinker. Imprinted polymer particles were introduced into a microchannel fabricated with a new material i.e. poly(methylvinylsiloxane) by simply rapid prototyping method. Imprinted effects were evaluated by laser-induced fluorescence (LIF) detection where the results indicated that good selective recognition for Z-L-Phe-OH-NBD in the imprinted polymer was obtained; the adsorption percentage of Z-L-Phe-OH-NBD was 61%. In contrast to conventional molecular imprinting analysis, integration shortened overall analysis time from 4h to 10 min.
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Affiliation(s)
- Jian-Du Lei
- Department of Chemistry, Tsinghua University, Beijing 100084, China
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36
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Kim H, Guiochon G. Thermodynamic Studies on the Solvent Effects In Chromatography on Molecularly Imprinted Polymers. 1. Nature of the Organic Modifier. Anal Chem 2005; 77:1708-17. [PMID: 15762576 DOI: 10.1021/ac040155f] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Molecularly imprinted polymers (MIPs) are used as highly enantioselective stationary phases in liquid chromatography. To optimize the binding performance of MIPs, different types of polar modifiers are frequently used. Previous studies have shown that the hydrogen-bonding donor parameter (HBD) of the modifier has a large influence on the binding performance of MIPs in chiral separations. This possibility is addressed in a detailed thermodynamic study of a Fmoc-L-tryptophan (Fmoc-L-Trp) imprinted polymer, eluted with four different polar modifiers, i.e., THF, propan-2-ol, methanol, and acetic acid, which have different HBDs (0.00, 0.33, 0.43, and 0.61, respectively). Adsorption isotherm data for each enantiomer in each of these organic modifiers were acquired by frontal analysis over a 20 000 dynamic concentration range. Nonlinear regression of the isotherm data, along with independent calculation of the affinity energy distributions, identified four different types of binding sites coexisting for the enantiomers on the MIP. The exception was acetic acid, which has the highest HBD. In this case, three types of binding sites only coexist on the MIP. The isotherm parameters obtained from these data show the following: (1) The association energies of the two enantiomers with a given type of sites have a similar magnitude; however, the density of the sites is higher for the template than for its antipode. (2) The nature of the organic modifier has a larger influence on the density of high-energy sites than on the association constant of these sites. (3) The molecular size of the organic modifier has a larger influence on the site density (especially for Fmoc-D-Trp) than does HBD. (4) Using an organic modifier with a higher HBD reduces the enantioselectivity on each site. (5) High-energy sites are more enantioselective than low-energy ones. (6) Using an organic modifier with a high HBD causes a larger reduction in the density of high-energy sites approached by the template molecules.
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Affiliation(s)
- Hyunjung Kim
- Department of Chemistry, University of Tennessee, Knoxville, Tennessee 37996-1600, USA
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37
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38
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Rushton GT, Karns CL, Shimizu KD. A critical examination of the use of the Freundlich isotherm in characterizing molecularly imprinted polymers (MIPs). Anal Chim Acta 2005. [DOI: 10.1016/j.aca.2004.07.048] [Citation(s) in RCA: 69] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
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39
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Li H, Nie L, Yao S. Adsorption Isotherms and Sites Distribution of Caffeic Acid ? Imprinted Polymer Monolith from Frontal Analysis. Chromatographia 2004. [DOI: 10.1365/s10337-004-0403-9] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
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40
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Garcés JL, Mas F, Puy J. Affinity distribution functions in multicomponent heterogeneous adsorption. Analytical inversion of isotherms to obtain affinity spectra. J Chem Phys 2004; 120:9266-76. [PMID: 15267863 DOI: 10.1063/1.1710857] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
An analytical approach for the interpretation of multicomponent heterogeneous adsorption or complexation isotherms in terms of multidimensional affinity spectra is presented. Fourier transform, applied to analyze the corresponding integral equation, leads to an inversion formula which allows the computation of the multicomponent affinity spectrum underlying a given competitive isotherm. Although a different mathematical methodology is used, this procedure can be seen as the extension to multicomponent systems of the classical Sips's work devoted to monocomponent systems. Furthermore, a methodology which yields analytical expressions for the main statistical properties (mean free energies of binding and covariance matrix) of multidimensional affinity spectra is reported. Thus, the level of binding correlation between the different components can be quantified. It has to be highlighted that the reported methodology does not require the knowledge of the affinity spectrum to calculate the means, variances, and covariance of the binding energies of the different components. Nonideal competitive consistent adsorption isotherm, widely used in metal/proton competitive complexation to environmental macromolecules, and Frumkin competitive isotherms are selected to illustrate the application of the reported results. Explicit analytical expressions for the affinity spectrum as well as for the matrix correlation are obtained for the NICCA case.
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Affiliation(s)
- Josep Lluís Garcés
- Research Center of Theoretical Chemistry and Department of Physical Chemistry, Facultat de Química, Barcelona University, C/Martí i Franqués, 1, E-08028 Barcelona, Catalonia, Spain
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41
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Striegler S. Designing selective sites in templated polymers utilizing coordinative bonds. J Chromatogr B Analyt Technol Biomed Life Sci 2004; 804:183-95. [PMID: 15093172 DOI: 10.1016/j.jchromb.2004.01.065] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
This review gives a survey over recent achievements on the design of selective sites in templated polymers. Particularly, coordinative bonds as driving force for the interaction between a substrate and a templated polymer are discussed. Recent achievements on the selective recognition of larger molecules, such as dipeptides and disaccharides, are highlighted that promise a fast development on biomolecule templated material towards enzyme-like catalysis in the up-coming years. Additionally, the achievements on the incorporation of catalytic centers based on transition metal complexes are summarized.
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Affiliation(s)
- Susanne Striegler
- Division of Inorganic Chemistry II, University of Ulm, Albert-Einstein-Allee 11, D-89069 Ulm, Germany.
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Abstract
The selectivity of analytical methods based on molecularly imprinted polymers (MIPs) is due to the preferential adsorption of the analyte(s) as compared to other substances (interferences). This paper shows the theoretical and practical difficulties, which have to be considered and solved when real samples need to be analysed in a wide range of analyte and interferant concentrations. It is shown that the estimation of interference effects requires either many measurements or a realistic model of the adsorption equilibrium in mixed solutions of the analyte and the interferences. Examples are shown for positive (cooperative) interference effects, for better experimental design and interpretation of binary isotherm measurements and for establishing the chemical model of interference from selectivity measurements. The usual MIP model consisting of a cavity, which closely fits the shape of the template from all sides, appears unsuitable for this MIP, and it is replaced with a more realistic, more open model. The applicability of the results to using non-imprinted polymers as selective sorbents and to screening drug candidates is also shown.
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Affiliation(s)
- Tímea Pap
- Research Group of Technical Analytical Chemistry, Hungarian Academy of Sciences, Budapest University of Technology and Economics, Szt. Gellért tér 4, H-1111 Budapest, Hungary.
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Theodoridis G, Zacharis CK, Tzanavaras PD, Themelis DG, Economou A. Automated sample preparation based on the sequential injection principle. J Chromatogr A 2004; 1030:69-76. [PMID: 15043255 DOI: 10.1016/j.chroma.2003.12.036] [Citation(s) in RCA: 69] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
A molecularly imprinted polymer (MIP) prepared using caffeine, as a template, was validated as a selective sorbent for solid-phase extraction (SPE), within an automated on-line sample preparation method. The polymer produced was packed in a polypropylene cartridge, which was incorporated in a flow system prior to the HPLC analytical instrumentation. The principle of sequential injection was utilised for a rapid automated and efficient SPE procedure on the MIP. Samples, buffers, washing and elution solvents were introduced to the extraction cartridge via a peristaltic pump and a multi-position valve, both controlled by appropriate software developed in-house. The method was optimised in terms of flow rates, extraction time and volume. After extraction, the final eluent from the extraction cartridge was directed to the injection loop and was subsequently analysed on HPLC. The overall set-up facilitated unattended operation, operation and improved both mixing fluidics and method development flexibility. This system may be readily built in the laboratory and can be further used as an automated platform for on-line sample preparation.
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Affiliation(s)
- Georgios Theodoridis
- Laboratory of Analytical Chemistry, Department of Chemistry, Aristotle University of Thessaloniki, GR-541 24 Thessaloniki, Greece.
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Baggiani C, Giraudi G, Giovannoli C, Tozzi C, Anfossi L. Adsorption isotherms of a molecular imprinted polymer prepared in the presence of a polymerisable template. Anal Chim Acta 2004. [DOI: 10.1016/s0003-2670(03)00671-8] [Citation(s) in RCA: 70] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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45
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Stanley BJ, Krance J. Analysis of active sites and heterogeneity in commercial reversed-phase octadecylsilanated silica with numerically calculated sorption distributions. J Chromatogr A 2003; 1011:11-22. [PMID: 14518758 DOI: 10.1016/s0021-9673(03)01143-9] [Citation(s) in RCA: 19] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
Abstract
Sorption isotherms spanning six orders of magnitude of pyridine concentration in a 60:40 methanol:water mobile phase adjusted to pH 5 were obtained with the frontal analysis method on three ODS stationary phases: Zorbax Pro-10/150, Vydac 218TPB10, and YMC 120AS10. The data was fit to a heterogeneous Langmuir model in which the association constant, K, is continuously distributed over a finite range of values. The results indicate a small degree of secondary adsorption for all three phases as a separate peak in K-space at higher values of K than the primary hydrophobic partitioning, and additional adsorption at even higher K values for the Zorbax and to a much smaller degree the YMC phase. Integration of the distributions yields the amount of sorption at each of the modeled sites. The results correlate with information known about the synthesis of these phases and the degree of band tailing in elution experiments at these conditions.
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Affiliation(s)
- Brett J Stanley
- Department of Chemistry, California State University, 5500 University Parkway, San Bernardino, CA 92407-2397, USA.
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Kim H, Spivak DA. New Insight into Modeling Non-Covalently Imprinted Polymers. J Am Chem Soc 2003; 125:11269-75. [PMID: 16220948 DOI: 10.1021/ja0361502] [Citation(s) in RCA: 74] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Three series of polymers were carefully formulated with increasing amounts of template while keeping the polymer components constant. The number of binding sites (N) and the number average association constant (K(n)()) were calculated for each polymer in a series, using equations adapted from the literature describing molecularly imprinted polymers (MIPs). The trends of N and K(n)() for each series of polymers, which were graphed versus percent template, suggest multiple functional monomers in the binding sites of noncovalent MIPs. This new insight has implications for understanding the underlying mechanisms for the formation of binding sites in the MIPs studied.
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Affiliation(s)
- Hyunjung Kim
- Department of Chemistry, Louisiana State University, Baton Rouge, Louisiana 70803, USA
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