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Jorge C. Masini - One of the best experts on this subject based on the ideXlab platform.
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Improving the Detectability of Sequential Injection Chromatography (SIC): Determination of Triazines by Exploiting Liquid Core Waveguide (LCW) Detection
Analytical Letters, 2011Co-Authors: Carlos M. C. Infante, Ricardo De Prá Urio, Jorge C. MasiniAbstract:Coupling a liquid core waveguide cell to a sequential injection chromatograph improved the detection limits for determination of triazine herbicides without compromising peak resolution. Separation of simazine, atrazine, and Propazine was achieved in water samples by a 25 mm long C18 monolithic column. Detection was made at 238 nm using a type II LCW (silica capillary coated with Teflon® AF2400) cell with 100 cm of optical path length. Detection limits for simazine, atrazine, and Propazine were 2.3, 1.9, and 4.5 µg L−1, respectively. Reduced analysis time and low solvent consumption are other remarkable features of the proposed method.
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development of a sequential injection chromatography sic method for determination of simazine atrazine and Propazine
IEEE Journal of Solid-state Circuits, 2009Co-Authors: Luciana Dos B O Santos, Carlos M. C. Infante, Jorge C. MasiniAbstract:: This paper describes the development of a sequential injection chromatography (SIC) procedure for separation and quantification of the herbicides simazine, atrazine, and Propazine exploring the low backpressure of a 2.5 cm long monolithic C(18) column. The separation of the three compounds was achieved in less than 90 s with resolution >1.5 using a mobile phase composed by ACN/1.25 mmol/L acetate buffer (pH 4.5) at the volumetric ratio of 35:65 and flow rate of 40 microL/s. Detection was made at 223 nm using a flow cell with 40 mm of optical path length. The LOD was 10 microg/L for the three triazines and the quantification limits were of 30 microg/L for simazine and Propazine and 40 microg/L for atrazine. The sampling frequency is 27 samples per hour, consuming 1.1 mL of ACN per analysis. The proposed methodology was applied to spiked water samples and no statistically significant differences were observed in comparison to a conventional HPLC-UV method. The major metabolites of atrazine and other herbicides did not interfere in the analysis, being eluted from the column either together with the unretained peak, or at retention times well-resolved from the studied compounds.
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sorption of atrazine Propazine deethylatrazine deisopropylatrazine and hydroxyatrazine onto organovermiculite
Journal of the Brazilian Chemical Society, 2005Co-Authors: Gilberto Abate, Jorge C. MasiniAbstract:The interaction of atrazine (AT), Propazine (PROP), deethylatrazine (DEA), deisopropylatrazine (DIA) and hydroxyatrazine (HAT) was studied with the clay mineral vermiculite saturated with K+ (VTK), and with the mineral modified by insertion of hexadecyltrimethyl-ammonium (HDTMA-VT) in the interlayer of VTK. The crude VTK exhibited negligible interaction with AT, PROP and DEA, moderate interaction with DIA and strong interaction with HAT. For the HDTMA-VT materials, removal percentages from aqueous medium for initial concentrations between 0.05 and 1.00 mg L-1 were 56 to 63% for AT, 43 to 45% for DEA, 12 to 19% for HAT and 77 to 78% for PROP. Sorption of AT, DEA and PROP onto HDTMA-VT was significantly enhanced in comparison to VTK. Ionic strength and pH had no significant influence on the sorption process. Desorption of all compounds from HDTMA-VT after 24 h of contact time was between 20 and 30% of the amount initially adsorbed.
S. A. Eremin - One of the best experts on this subject based on the ideXlab platform.
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A quenching fluoroimmunoassay for analysis of the pesticide Propazine in an apolar organic solvent, reverse micelles of AOT inn-octane: Effect of the micellar matrix and labeled antigen structure
Journal of Fluorescence, 1997Co-Authors: E. G. Matveeva, J. V. Samsonova, S. A. EreminAbstract:A simple way of directly observing antigen-antibody binding in a reverse micellar system, n -octane containing reverse micelles of aerosol OT (AOT), using the hydrophobic pesticide Propazine as antigen, is described. We observed two processes during fluorescein-labeled Propazine (FP)-antibody (Ab) interaction in reverse micelles: (1) quenching of the fluorescence of FP after mixing of Ab and FP (due immune complex formation) and (2) restoration of FP fluorescence after addition of excess Propazine to the immune complex formed. We found that the quenching efficiency depends on both the properties of the reverse micellar system (surfactant concentration, hydration degree W _0 = [water]/[surfactant]) and the structure of the labeled antigen. A quenching fluoroimmunoassay of Propazine both in apolar organic solvents and in water is developed. The method is homogeneous. The quenching time is 10–30 min, and the detection limit of Propazine is 100 nM (20 Μg/L) in organic solvent and 10 nM (2 Μg/L) in water. Propazine can be added to the reverse micellar system when dissolved in AOT/octane, or in an octane/chloroform mixture, or in chloroform. This makes possible the use of the analysis directly for pesticide extracts in nonpolar organic solvents.
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a quenching fluoroimmunoassay for analysis of the pesticide Propazine in an apolar organic solvent reverse micelles of aot in n octane effect of the micellar matrix and labeled antigen structure
Journal of Fluorescence, 1997Co-Authors: E. G. Matveeva, J. V. Samsonova, S. A. EreminAbstract:A simple way of directly observing antigen-antibody binding in a reverse micellar system,n-octane containing reverse micelles of aerosol OT (AOT), using the hydrophobic pesticide Propazine as antigen, is described. We observed two processes during fluorescein-labeled Propazine (FP)-antibody (Ab) interaction in reverse micelles: (1) quenching of the fluorescence of FP after mixing of Ab and FP (due immune complex formation) and (2) restoration of FP fluorescence after addition of excess Propazine to the immune complex formed. We found that the quenching efficiency depends on both the properties of the reverse micellar system (surfactant concentration, hydration degreeW 0 = [water]/[surfactant]) and the structure of the labeled antigen. A quenching fluoroimmunoassay of Propazine both in apolar organic solvents and in water is developed. The method is homogeneous. The quenching time is 10–30 min, and the detection limit of Propazine is 100 nM (20 Μg/L) in organic solvent and 10nM (2 Μg/L) in water. Propazine can be added to the reverse micellar system when dissolved in AOT/octane, or in an octane/chloroform mixture, or in chloroform. This makes possible the use of the analysis directly for pesticide extracts in nonpolar organic solvents.
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polarization fluoroimmunoassay of Propazine in reversed micelles of aerosol ot in octane
Bioorganicheskaia khimiia, 1996Co-Authors: E. G. Matveeva, Zh V Samsonova, S. A. EreminAbstract:: The interaction between fluorescein-labeled Propazine and antibodies against this hapten was studied in the reversed micelles of Aerosol OT in n-octane by a polarization fluoroassay. The effect of the hydration degree of micelles W0 (W0=[H2O]/[Surf]), which determines their size and surfactant concentration, on the binding of the antigen with antibodies was studied. A high hydration degree of the reversed micelles (W0 = 15-30) and low concentration of the surfactant (less than 50 microM) are optimal for binding. The binding efficacy depends upon the structure of the fluorescein-labeled hapten, particularly upon the length of the bridge binding fluorescein with Propazine. It was shown that the polarization fluoroimmunoassay of Propazine may be carried out in a reversed micellar system in nonpolar organic solvent (octane) with a detection limit of about 100 nM (20 microns/l). This is an order of magnitude higher than that achievable upon analysis in aqueous medium. The proposed polarization fluoroimmunoassay in a reversed micellar system makes it possible to detect haptens that are poorly soluble in water directly in organic extracts, e.g. in chloroform solutions.
C Perezconde - One of the best experts on this subject based on the ideXlab platform.
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semi covalent imprinted polymer using Propazine methacrylate as template molecule for the clean up of triazines in soil and vegetable samples
Journal of Chromatography A, 2006Co-Authors: C Cacho, A Martinesteban, Esther Turiel, D Ayala, C PerezcondeAbstract:Abstract A semi-covalent imprinted polymer was prepared by precipitation polymerisation using Propazine methacrylate as template molecule, ethylene glycol dimethacrylate as cross-linker and toluene as porogen. After removal of Propazine by basic hydrolysis of the covalent bond, the optimum loading, washing and elution conditions for the solid-phase extraction of the selected triazines were established. The binding sites present in the polymeric matrix were characterised by fitting the experimental results of several rebinding studies to the Langmuir–Freundlich isotherm. Subsequently, an analytical methodology based on molecularly imprinted solid-phase extraction (MISPE) was developed for the determination of several triazinic herbicides in soil and vegetable samples. Following this procedure, a good degree of clean-up of the sample extracts was easily achieved, allowing the HPLC-UV determination of selected triazines in complex samples at low concentration levels.
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characterisation and quality assessment of binding sites on a Propazine imprinted polymer prepared by precipitation polymerisation
Journal of Chromatography B, 2004Co-Authors: C Cacho, E Turiel, A Martinesteban, C Perezconde, Carmen CamaraAbstract:Abstract In this paper, the Langmuir–Freundlich isotherm (LF) is used to characterise a Propazine-imprinted polymer obtained by precipitation polymerisation (MIP-P). Different rebinding studies were carried out allowing to explain the different interactions taking place between the molecularly imprinted polymer and six triazinic herbicides (desisopropylatrazine, desethylatrazine, simazine, atrazine, Propazine and prometryn). The LF fitting parameters obtained (total number of binding sites, heterogeneity index and mean binding affinity) were compared to those obtained in a previous work for a Propazine-imprinted polymer prepared by bulk polymerisation (MIP-B). From that study, it was concluded that precipitation polymerisation yielded polymers with a more homogeneous binding site distribution and higher affinity constants.
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clean up of triazines in vegetable extracts by molecularly imprinted solid phase extraction using a Propazine imprinted polymer
Analytical and Bioanalytical Chemistry, 2003Co-Authors: C Cacho, A Martinesteban, C Perezconde, Esther Turiel, Carmen CamaraAbstract:An analytical methodology based on a molecularly imprinted solid-phase extraction (MISPE) procedure was developed for the determination of several triazines (atrazine, simazine, desethylatrazine (DEA), desisopropylatrazine (DIA), and Propazine) in vegetable samples. A methacrylic acid-based imprinted polymer was prepared by precipitation polymerisation using Propazine as template and toluene as porogen. After removal of the template by Soxhlet extraction, the optimum loading, washing, and elution conditions for MISPE of the selected triazines were established. The optimised MISPE procedure was applied to the extraction of the selected triazines in pea, potato, and corn sample extracts and a high degree of clean-up was obtained. However, some remaining interferences, non-specifically and strongly bound to the polymeric matrix, appeared in the chromatogram, preventing quantification of DIA in potatoes and DIA, DEA, and Propazine in corn samples. Thus, a new clean-up protocol based on the use of a non-imprinted polymer for removal of these interferences prior to the MISPE step was developed. By following the new two-step MISPE procedure, the matrix compounds were almost completely removed, allowing the determination of all the triazines selected at concentration levels below the established maximum residue limits, making the developed procedure suitable for monitoring these analytes in vegetable samples.
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assessment of the cross reactivity and binding sites characterisation of a Propazine imprinted polymer using the langmuir freundlich isotherm
Analyst, 2003Co-Authors: Esther Turiel, C Perezconde, A MartinestebanAbstract:In this paper, the Langmuir-Freundlich isotherm is used to model the interaction of several triazines (desethylatrazine, desisopropylatrazine, simazine, atrazine, Propazine and prometryn) with a Propazine-imprinted polymer and to explain the observed cross-reactivity. Different rebinding experiments (each herbicide alone or all together in a mixture) were carried out and the experimental binding isotherms were fitted to the Langmuir-Freundlich isotherm. The fitting coefficients obtained (total number of binding sites, mean binding affinity and heterogeneity index) allowed the description of the kind of binding sites present in the imprinted polymer under study. It was concluded that the recognition mechanism was mainly governed by the molecular size although slight differences in the molecular structure may also play an important role. The obtained results suggest that the use of this new methodology can open new pathways for understanding how molecular recognition in imprinted polymers takes place.
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molecular recognition in a Propazine imprinted polymer and its application to the determination of triazines in environmental samples
Analytical Chemistry, 2001Co-Authors: Esther Turiel, C Perezconde, Antonio Martinesteban, P Fernandez, Carmen CamaraAbstract:An analytical methodology for the determination of triazines in environmental samples incorporating a molecularly imprinted solid-phase extraction (MISPE) process using a Propazine-imprinted polymer was developed. Two different polymers were prepared using acetonitrile or toluene as porogen, and their optimum loading, washing, and elution conditions were established. Although both polymers were able to recognize several chlorotriazines (Propazine, atrazine, simazine, desethylatrazine, and desisopropylatrazine), the polymer prepared in toluene showed the best performance and was also capable of recognizing a methylthiotriazine (prometryn). A binding study carried out in this polymer demonstrated that it possesses heterogeneous binding sites with different binding abilities. From this study, it was also concluded that desethylatrazine and desisopropylatrazine displace the other triazines at high concentrations, including the template molecule. The accuracy and selectivity of the MISPE process developed was ...
A Martinesteban - One of the best experts on this subject based on the ideXlab platform.
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semi covalent imprinted polymer using Propazine methacrylate as template molecule for the clean up of triazines in soil and vegetable samples
Journal of Chromatography A, 2006Co-Authors: C Cacho, A Martinesteban, Esther Turiel, D Ayala, C PerezcondeAbstract:Abstract A semi-covalent imprinted polymer was prepared by precipitation polymerisation using Propazine methacrylate as template molecule, ethylene glycol dimethacrylate as cross-linker and toluene as porogen. After removal of Propazine by basic hydrolysis of the covalent bond, the optimum loading, washing and elution conditions for the solid-phase extraction of the selected triazines were established. The binding sites present in the polymeric matrix were characterised by fitting the experimental results of several rebinding studies to the Langmuir–Freundlich isotherm. Subsequently, an analytical methodology based on molecularly imprinted solid-phase extraction (MISPE) was developed for the determination of several triazinic herbicides in soil and vegetable samples. Following this procedure, a good degree of clean-up of the sample extracts was easily achieved, allowing the HPLC-UV determination of selected triazines in complex samples at low concentration levels.
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synthesis and evaluation of new Propazine imprinted polymer formats for use as stationary phases in liquid chromatography
Analytica Chimica Acta, 2005Co-Authors: F G Tamayo, A Martinesteban, Mariamagdalena Titirici, Boerje SellergrenAbstract:Abstract Silica particles have been used as supports for the preparation of three different Propazine-imprinted polymer formats. First format refers to grafting of thin films of molecularly imprinted polymers (MIPs) using an immobilised iniferter-type initiator (inif-MIP). The other two new formats were obtained by complete filling of the silica pores with the appropriate polymerisation mixture leading to a silica–MIP composite material (c-MIP) followed by the dissolution of the silica matrix resulting in spherical MIP beads (dis-MIP). These techniques offer a mean of fine-tuning the particle morphology of the resulting MIP particles leading to enhanced capacity in chromatographic applications. Porous silica (specific surface area S = 380 m2 g−1, particle size ps = 10 μm, pore volume Vp = 1.083 ml g−1 and pore diameter dp = 10.5 nm), methacrylic acid and ethylenglycol dimethacrylate were used for the preparation of the materials. All the MIP formats imprinted with Propazine have been characterised by elemental analysis, FT-IR spectroscopy, nitrogen adsorption and scanning electron microscopy. Further, the materials were assessed as stationary phases in HPLC. Capacity factors, imprinting factors and theoretical plate numbers were calculated for Propazine and other related triazines in order to compare the chromatographic properties of the three different stationary phases. For the inif-MIPs the column efficiency depended strongly on the amount of grafted polymer. Thus, only the polymers grafted as thin films of ca. 1.3 nm average thickness show imprinting effects and the highest column efficiency giving plate numbers (N) of 1600 m−1 for the imprinted Propazine. The performance of the c-MIP stationary phase decreases as result of the complete pore filling after polymerisation and increases again after the removal of the silica matrix due to a better mass transfer in the porous mirror-image resulting polymer. From this study can be concluded that the inif-MIP shows the best efficiency for use as stationary phase in HPLC for the separation of triazinic herbicides.
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characterisation and quality assessment of binding sites on a Propazine imprinted polymer prepared by precipitation polymerisation
Journal of Chromatography B, 2004Co-Authors: C Cacho, E Turiel, A Martinesteban, C Perezconde, Carmen CamaraAbstract:Abstract In this paper, the Langmuir–Freundlich isotherm (LF) is used to characterise a Propazine-imprinted polymer obtained by precipitation polymerisation (MIP-P). Different rebinding studies were carried out allowing to explain the different interactions taking place between the molecularly imprinted polymer and six triazinic herbicides (desisopropylatrazine, desethylatrazine, simazine, atrazine, Propazine and prometryn). The LF fitting parameters obtained (total number of binding sites, heterogeneity index and mean binding affinity) were compared to those obtained in a previous work for a Propazine-imprinted polymer prepared by bulk polymerisation (MIP-B). From that study, it was concluded that precipitation polymerisation yielded polymers with a more homogeneous binding site distribution and higher affinity constants.
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clean up of triazines in vegetable extracts by molecularly imprinted solid phase extraction using a Propazine imprinted polymer
Analytical and Bioanalytical Chemistry, 2003Co-Authors: C Cacho, A Martinesteban, C Perezconde, Esther Turiel, Carmen CamaraAbstract:An analytical methodology based on a molecularly imprinted solid-phase extraction (MISPE) procedure was developed for the determination of several triazines (atrazine, simazine, desethylatrazine (DEA), desisopropylatrazine (DIA), and Propazine) in vegetable samples. A methacrylic acid-based imprinted polymer was prepared by precipitation polymerisation using Propazine as template and toluene as porogen. After removal of the template by Soxhlet extraction, the optimum loading, washing, and elution conditions for MISPE of the selected triazines were established. The optimised MISPE procedure was applied to the extraction of the selected triazines in pea, potato, and corn sample extracts and a high degree of clean-up was obtained. However, some remaining interferences, non-specifically and strongly bound to the polymeric matrix, appeared in the chromatogram, preventing quantification of DIA in potatoes and DIA, DEA, and Propazine in corn samples. Thus, a new clean-up protocol based on the use of a non-imprinted polymer for removal of these interferences prior to the MISPE step was developed. By following the new two-step MISPE procedure, the matrix compounds were almost completely removed, allowing the determination of all the triazines selected at concentration levels below the established maximum residue limits, making the developed procedure suitable for monitoring these analytes in vegetable samples.
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assessment of the cross reactivity and binding sites characterisation of a Propazine imprinted polymer using the langmuir freundlich isotherm
Analyst, 2003Co-Authors: Esther Turiel, C Perezconde, A MartinestebanAbstract:In this paper, the Langmuir-Freundlich isotherm is used to model the interaction of several triazines (desethylatrazine, desisopropylatrazine, simazine, atrazine, Propazine and prometryn) with a Propazine-imprinted polymer and to explain the observed cross-reactivity. Different rebinding experiments (each herbicide alone or all together in a mixture) were carried out and the experimental binding isotherms were fitted to the Langmuir-Freundlich isotherm. The fitting coefficients obtained (total number of binding sites, mean binding affinity and heterogeneity index) allowed the description of the kind of binding sites present in the imprinted polymer under study. It was concluded that the recognition mechanism was mainly governed by the molecular size although slight differences in the molecular structure may also play an important role. The obtained results suggest that the use of this new methodology can open new pathways for understanding how molecular recognition in imprinted polymers takes place.
Esther Turiel - One of the best experts on this subject based on the ideXlab platform.
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Surface modified-magnetic nanoparticles by molecular Imprinting for the dispersive solid-phase extraction of triazines from environmental waters.
IEEE Journal of Solid-state Circuits, 2020Co-Authors: Esther Turiel, Myriam Díaz-Álvarez, Antonio Martín-estebanAbstract:Magnetic nanoparticles have been surface modified by molecular imprinting and evaluated as selective sorbents for the extraction of triazines from environmental waters. The use of Propazine as template allowed to synthetize a selective material able to simultaneously recognize and selective extract not only the template but also several other herbicides of the same family. A magnetic molecularly imprinted-based dispersive solid-phase extraction procedure was developed and fully optimized. Magnetic molecularly imprinted polymer particles can be easily collected and separated from liquid solvents and samples with the help of an external magnetic field, avoiding in that way any centrifugation or filtration steps, which represents a remarkable advantage over traditional procedures. Under optimum conditions, selective extraction of several triazines (cyanazine, simazine, atrazine, Propazine and terbutylazine) from environmental water samples was performed prior to final determination by high-performance liquid chromatography with diode-array detection. Recoveries for the studied triazines were within the range 75.2-94.1%, with relative standard deviations lower than 11.3 % (n = 3). The limits of detection were within 0.16-0.51 μg L-1 , depending upon the triazine and the type of sample analyzed. This article is protected by copyright. All rights reserved.
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semi covalent imprinted polymer using Propazine methacrylate as template molecule for the clean up of triazines in soil and vegetable samples
Journal of Chromatography A, 2006Co-Authors: C Cacho, A Martinesteban, Esther Turiel, D Ayala, C PerezcondeAbstract:Abstract A semi-covalent imprinted polymer was prepared by precipitation polymerisation using Propazine methacrylate as template molecule, ethylene glycol dimethacrylate as cross-linker and toluene as porogen. After removal of Propazine by basic hydrolysis of the covalent bond, the optimum loading, washing and elution conditions for the solid-phase extraction of the selected triazines were established. The binding sites present in the polymeric matrix were characterised by fitting the experimental results of several rebinding studies to the Langmuir–Freundlich isotherm. Subsequently, an analytical methodology based on molecularly imprinted solid-phase extraction (MISPE) was developed for the determination of several triazinic herbicides in soil and vegetable samples. Following this procedure, a good degree of clean-up of the sample extracts was easily achieved, allowing the HPLC-UV determination of selected triazines in complex samples at low concentration levels.
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clean up of triazines in vegetable extracts by molecularly imprinted solid phase extraction using a Propazine imprinted polymer
Analytical and Bioanalytical Chemistry, 2003Co-Authors: C Cacho, A Martinesteban, C Perezconde, Esther Turiel, Carmen CamaraAbstract:An analytical methodology based on a molecularly imprinted solid-phase extraction (MISPE) procedure was developed for the determination of several triazines (atrazine, simazine, desethylatrazine (DEA), desisopropylatrazine (DIA), and Propazine) in vegetable samples. A methacrylic acid-based imprinted polymer was prepared by precipitation polymerisation using Propazine as template and toluene as porogen. After removal of the template by Soxhlet extraction, the optimum loading, washing, and elution conditions for MISPE of the selected triazines were established. The optimised MISPE procedure was applied to the extraction of the selected triazines in pea, potato, and corn sample extracts and a high degree of clean-up was obtained. However, some remaining interferences, non-specifically and strongly bound to the polymeric matrix, appeared in the chromatogram, preventing quantification of DIA in potatoes and DIA, DEA, and Propazine in corn samples. Thus, a new clean-up protocol based on the use of a non-imprinted polymer for removal of these interferences prior to the MISPE step was developed. By following the new two-step MISPE procedure, the matrix compounds were almost completely removed, allowing the determination of all the triazines selected at concentration levels below the established maximum residue limits, making the developed procedure suitable for monitoring these analytes in vegetable samples.
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assessment of the cross reactivity and binding sites characterisation of a Propazine imprinted polymer using the langmuir freundlich isotherm
Analyst, 2003Co-Authors: Esther Turiel, C Perezconde, A MartinestebanAbstract:In this paper, the Langmuir-Freundlich isotherm is used to model the interaction of several triazines (desethylatrazine, desisopropylatrazine, simazine, atrazine, Propazine and prometryn) with a Propazine-imprinted polymer and to explain the observed cross-reactivity. Different rebinding experiments (each herbicide alone or all together in a mixture) were carried out and the experimental binding isotherms were fitted to the Langmuir-Freundlich isotherm. The fitting coefficients obtained (total number of binding sites, mean binding affinity and heterogeneity index) allowed the description of the kind of binding sites present in the imprinted polymer under study. It was concluded that the recognition mechanism was mainly governed by the molecular size although slight differences in the molecular structure may also play an important role. The obtained results suggest that the use of this new methodology can open new pathways for understanding how molecular recognition in imprinted polymers takes place.
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molecular recognition in a Propazine imprinted polymer and its application to the determination of triazines in environmental samples
Analytical Chemistry, 2001Co-Authors: Esther Turiel, C Perezconde, Antonio Martinesteban, P Fernandez, Carmen CamaraAbstract:An analytical methodology for the determination of triazines in environmental samples incorporating a molecularly imprinted solid-phase extraction (MISPE) process using a Propazine-imprinted polymer was developed. Two different polymers were prepared using acetonitrile or toluene as porogen, and their optimum loading, washing, and elution conditions were established. Although both polymers were able to recognize several chlorotriazines (Propazine, atrazine, simazine, desethylatrazine, and desisopropylatrazine), the polymer prepared in toluene showed the best performance and was also capable of recognizing a methylthiotriazine (prometryn). A binding study carried out in this polymer demonstrated that it possesses heterogeneous binding sites with different binding abilities. From this study, it was also concluded that desethylatrazine and desisopropylatrazine displace the other triazines at high concentrations, including the template molecule. The accuracy and selectivity of the MISPE process developed was ...
