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La Chaussée-Saint-Victor, France

Puzio K.,CNRS Institute of Organic and Analytical Chemistry | Claude B.,CNRS Institute of Organic and Analytical Chemistry | Amalric L.,Bureau de Recherches Geologiques et Minieres | Berho C.,Bureau de Recherches Geologiques et Minieres | And 4 more authors.
Journal of Chromatography A | Year: 2014

Three molecularly imprinted polymers (MIPs) have been synthesized in order to bind efficiently glyphosate (GLY) in natural waters (mineral and underground). Since the target analyte is polar and hydrophilic, electrostatic interactions and hydrogen bonds have been favored with two templates (phenylphosphonic acid and diethyl(α-aminobenzyl)-phosphonic acid) and two functional monomers (1-allyl-2-thiourea and methacrylic acid). MIPs have been assessed by comparison of the recoveries obtained with MIP and NIP (non imprinted polymer) by solid-phase extraction (SPE). The selectivity of MIP versus NIP was satisfactory for the three imprinted polymers with a very straightforward protocol: conditioning of 250mg of MIP or NIP packed in 3-mL polypropylene cartridges with 3mL Milli-Q water, loading of Milli-Q water (15mL) spiked with 5mgL-1 of GLY and its metabolite, aminomethylphosphonic acid (AMPA) and elution by 3mL NH4OH (10mM) or 3mL HCl (100mM). SPE fractions were directly analyzed by capillary electrophoresis (CE). Thus, the recoveries of both analytes were greater than 80% for all MIPs and less than 25% for most NIPs. Moreover, the MIP prepared with 1-allyl-2-thiourea as functional monomer and phenylphosphonic acid as template displayed a capacity of 0.033μmol/mg for GLY. However, the substitution of Milli-Q water by mineral water caused the decrease of MIP recoveries, for that, a pretreatment of the sample by ionic exchange resins was set up and succeeded in improving recoveries (about 50% for GLY and 25% for AMPA). Then, groundwaters were spiked with low concentrations of GLY and AMPA (0.5μgL-1) and directly percolated through MIP cartridges. The extractions were carried out by triplicate and the elution fractions were analyzed by UPLC-MS/MS. The results showed no retention of AMPA but a total retention of GLY by MIP. © 2014 Elsevier B.V.

Polyintell | Date: 2011-03-07

A method for preparing a radioactive tracer provided with a radioactive fluorine isotope, including providing a precursor of the radioactive tracer, comprising at least one leaving group completely or partially formed by a labelling entity, wherein said leaving group can be moved by a fluoride ion, providing a molecularly imprinted polymer dedicated to the molecular recognition of at least the aforementioned labelling entity, exposing the precursor to a radioactive fluoride ion source under conditions suitable for movement of the leaving group by a radioactive fluoride ion, placing the mixture resulting from step (iii) in contact with the molecularly imprinted polymer under conditions suitable for the recognition of the labelling entity, and obtaining a solution containing the radioactive tracer provided with a radioactive isotope of fluorine obtained at the end of step (iii).

Ray J.V.,Queen Mary, University of London | Mirata F.,Queen Mary, University of London | Perollier C.,POLYINTELL | Arotcarena M.,POLYINTELL | And 2 more authors.
Analytical and Bioanalytical Chemistry | Year: 2016

A signalling molecularly imprinted polymer was synthesised for easy detection of tamoxifen and its metabolites. 6-Vinylcoumarin-4-carboxylic acid (VCC) was synthesised from 4-bromophenol to give a fluorescent monomer, designed to switch off upon binding of tamoxifen. Clomiphene, a chlorinated analogue, was used as the template for the imprinting, and its ability to quench the coumarin fluorescence when used in a 1:1 ratio was demonstrated. Tamoxifen and 4-hydroxytamoxifen were also shown to quench coumarin fluorescence. Imprinted and non-imprinted polymers were synthesised using VCC, methacrylic acid as a backbone monomer and ethylene glycol dimethacrylate as cross-linker, and were ground and sieved to particle sizes ranging between 45 and 25 μm. Rebinding experiments demonstrate that the imprinted polymer shows very strong affinity for both clomiphene and tamoxifen, while the non-imprinted polymer shows negligible rebinding. The fluorescence of the imprinted polymer is quenched by clomiphene, tamoxifen and 4-hydroxytamoxifen. The switch off in fluorescence of the imprinted polymer under these conditions could also be detected under a UV lamp with the naked eye, making this matrix suitable for applications when coupled with a sample preparation system. © 2016 The Author(s)

Analytica Chimica Acta | Year: 2010

The aim of this work was to develop a method for the clean-up and preconcentration of zearalenone from corn and wheat samples employing molecularly imprinted polymer (MIP) as selective sorbent for solid-phase extraction (SPE). Cereal samples were extracted with acetonitrile/water (75:25, v/v) and the extract was diluted with water and applied to an AFFINIMIP™ ZON MIP-SPE column. The column was then washed to eliminate the interferences and zearalenone was eluted with methanol and quantified using HPLC with fluorescence detection (λexc=275/λem=450nm). The precision and accuracy of the method were satisfactory for both cereals at the different fortification levels tested and it gave recoveries between 82 and 87% (RSDr 2.5-6.2%, n=3) and 86 and 90% (RSDr 0.9-6.8%, n=3) for wheat and maize, respectively. MIP-SPE column capacity was determined to be not less than 6.6μg of zearalenone and to be at least four times higher than that of immunoaffinity column (IAC). The application of AFFINIMIP™ ZON molecularly imprinted polymer as a selective sorbent material for detection of zearalenone fulfilled the method performance criteria required by the Commission Regulation (EC) No. 401/2006, demonstrating the suitability of the technique for the control of zearalenone in cereal samples. © 2010 Elsevier B.V.

Ali W.H.,ESPCI ParisTech | Derrien D.,POLYINTELL | Alix F.,POLYINTELL | Perollier C.,POLYINTELL | And 4 more authors.
Journal of Chromatography A | Year: 2010

The aim of this work was to develop a method for the clean-up of a mycotoxin, i.e. Ochratoxin A (OTA), from cereal extracts employing a new molecularly imprinted polymer (MIP) as selective sorbent for solid-phase extraction (SPE) and to compare with an immunoaffinity column. A first series of experiments was carried out in pure solvents to estimate the potential of the imprinted sorbent in terms of selectivity studying the retention of OTA on the MIP and on a non-imprinted polymer using conventional crushed monolith. The selectivity of the MIP was also checked by its application to wheat extracts. Then, after this feasibility study, two different formats of MIP: crushed monolith and micro-beads were evaluated and compared. Therefore an optimization procedure was applied to the selective extraction from wheat using the MIP beads. The whole procedure was validated by applying it to wheat extract spiked by OTA at different concentration levels and then to a certified contaminated wheat sample. Recoveries close to 100% were obtained. The high selectivity brought by the MIP was compared to the selectivity by an immunoaffinity cartridge for the clean-up of the same wheat sample. The study of capacity of both showed a significant higher capacity of the MIP. © 2010 Elsevier B.V.

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