MOLECULARLY IMPRINTED POLYMER AND ITS USE FOR QUANTIFYING A PESTICIDE IN A SAMPLE

Description

[0001] The present invention relates to a molecularly imprinted polymer, and its use in the quantification of a pesticide in a sample. The invention also relates to a method for preparing said polymer.

[0002] Chlordecone (CLD) is a persistent organochlorine pesticide included in the 2009 Stockholm Convention, which bans or restricts the use of 21 hazardous pesticides and products. It was widely used in the French Antilles from 1972 to control the banana weevil. It was banned in 1990 but used under exemption until 1993. However, due to its persistence and extensive use, it is still found in Caribbean soils, river water, groundwater, and marine environments. Chlordecone is metabolized in the human liver by chlordecone reductase to produce chlordecol (CLDOH).

[0003] Over time, methods for measuring chlordecone and chlordecol have been developed. However, these methods lack selectivity due to the presence of other components in the samples to be analyzed, which can interfere with the analysis.

[0004] There is therefore a need to have means of being able to purify a sample, in order to ensure the selectivity of the analysis, and to be able to quantify pesticides in a reliable and repeatable manner.

[0005] Recently, molecularly imprinted polymers (MIPs) have been developed for sample processing prior to analysis. These are polymers that have been specifically designed to have an affinity for the product to be analyzed. To do this, the polymer was manufactured in the presence of the molecule of interest or a structural analogue, so that in the 3D structure of said polymer, there are sites that can accommodate said molecule and retain it (US 2012 / 052757 A1, CN 110117342 A and CN 112694564 A).

[0006] However, these polymers are difficult to design because the success of this approach depends on very specific polymerization conditions, particularly with respect to the choice of monomers, crosslinking agent, and porogen. As a result, and to date, no polymer that can effectively retain chlordecone and / or chlordecol has been prepared, despite the obvious interest that such a polymer represents. CONTEXT OF THE INVENTION

[0007] One of the aims of the invention is to provide a molecularly imprinted polymer.

[0008] Another object of the present invention is a method for preparing a molecularly imprinted polymer.

[0009] Another aim of the invention is to be able to use said molecularly imprinted polymer in the detection and / or quantification of a pesticide.

[0010] Yet another aim of the invention is to provide a method for preparing the sample upstream of the analysis for the detection and / or quantification of a pesticide in various media, such as for example serum.

[0011] The inventors have initiated extensive research to develop a molecularly imprinted polymer with adequate chlordecone and / or chlordecol retention properties, which can be used in the analysis of samples for this pesticide and / or its main metabolite.

[0012] A first object of the present invention is a molecularly imprinted polymer (MIP) wherein the polymer is poly-4-vinylpyridine, or poly-2-vinylpyridine, crosslinked by a crosslinking agent, wherein the crosslinking agent is selected from ethylene glycol dimethacrylate (EGDMA), trimethylolpropane trimethacrylate (TRIM) and pentaerythritol triacrylate (PETRA), said molecularly imprinted polymer containing imprinting sites for chlordecol and / or chlordecone.

[0013] The present invention relates to a molecularly imprinted polymer (MIP) wherein the polymer is poly-4-vinylpyridine, or poly-2-vinylpyridine, crosslinked by a crosslinking agent, wherein the crosslinking agent is selected from ethylene glycol dimethacrylate (EGDMA), trimethylolpropane trimethacrylate (TRIM) and pentaerythritol triacrylate (PETRA), said molecularly imprinted polymer containing imprinting sites for chlordecol and / or chlordecone, in particular wherein the polymer is poly-4-vinylpyridine crosslinked with ethylene glycol dimethacrylate (EGDMA).

[0014] By "molecularly imprinted polymer" within the meaning of the present invention, a synthetic polymer is understood to mean, comprising receptor sites capable of accommodating an organic molecule, namely chlordecone and / or chlordecol.

[0015] The chemical structure of the receptor sites allows interactions with the target molecules to take place, such as non-covalent van der Waals-type interactions.

[0016] Thus, the molecularly imprinted polymer can “ capture» the molecule targets reversibly, and selectively, compared to other components, or « interfering ", which may be present in the sample to be analyzed.

[0017] Among the interferers, we can cite in particular other classes of pesticides, main compounds of the matrix (proteins for meat products or serum, pigments for products of plant origin, salts for urine).

[0018] By " reversible » it is understood that the target molecule is retained by the molecularly imprinted polymer, by non-covalent bonds, and can be removed without chemical modification of said target molecule, and of said molecularly imprinted polymer. The removal being carried out by the use of a solvent capable of breaking the non-covalent interactions between the target molecule and the molecularly imprinted polymer.

[0019] By " selective» it is understood that the molecularly imprinted polymer has a better affinity for the target molecule compared to other components that may be contained in the sample to be analyzed.

[0020] By " footprint sites » we mean the above-mentioned receptor sites, schematically represented in the Figures 1C and 1D . The imprinting sites in the molecularly imprinted polymer according to the present invention are sites available to accommodate chlordecone and / or chlordecol, and therefore do not already contain said molecules. It is therefore, unless otherwise indicated, a molecularly imprinted polymer devoid of chlordecone and / or chlordecol.

[0021] 4-Vinylpyridine (4-VP) and 2-vinylpyridine (2-VP) are monomers that can undergo free radical polymerization to yield poly-4-vinylpyridine and poly-2-vinylpyridine respectively. The structures of the two monomers are shown below:

[0022] The crosslinking agents used in the present invention have acrylate-type units and have the following structures:

[0023] For the purposes of the present invention, the term “ "crosslinked polymer" the fact that the monomer and the crosslinking agent have been copolymerized.

[0024] Chlordecone, marketed in the formulations Kepone ®< , Curlone ®< or Merex ®< , is a polychlorinated molecule whose IUPAC name is “1,2,3,4,6,7,8,9,10,10-decarchloropenta-cyclo[5.3.0.0 2,6< .0 3,9< .0 4,8< ]decan-5-one”.

[0025] Chlordecol, or « 1,2,3,4,6,7,8,9, 10, 10-decachloro-pentacyclo[5.3.0.0 2.6< .0 3.9< .0 4.8< ]decan-5- ol" is a compound with a structure similar to that of chlordecone, but with a hydroxyl function instead of a ketone function.

[0026] According to a particular embodiment, the present invention relates to a molecularly imprinted polymer (MIP) in which the polymer is poly-4-vinylpyridine (4 VP MIP), crosslinked by a crosslinking agent, wherein the crosslinking agent is selected from ethylene glycol dimethacrylate (EGDMA), trimethylolpropane trimethacrylate (TRIM) and pentaerythritol triacrylate (PETRA), said molecularly imprinted polymer containing imprinting sites for chlordecol and / or chlordecone.

[0027] According to a particular embodiment, the present invention relates to a molecularly imprinted polymer as defined above, in which the polymer is poly-4-vinylpyridine crosslinked with ethylene glycol dimethacrylate (EGDMA).

[0028] According to another particular embodiment, the present invention relates to a molecularly imprinted polymer as defined above, imprinted with chlordecol.

[0029] According to this particular embodiment, the imprint sites are formed from chlordecol. The inventors have surprisingly found and demonstrated that the molecularly imprinted polymer thus formed is capable of retaining not only chlordecol used in its preparation, but also chlordecone, despite the fact that chlordecone does not possess the hydroxyl function of chlordecol.

[0030] According to another particular embodiment, the present invention relates to a molecularly imprinted polymer as defined above, said molecularly imprinted polymer having a capacity to retain chlordecone at a rate of 36 µg per gram of polymer. In the following, the compound to be retained, namely chlordecone and / or chlordecol, is also called " analyte ".

[0031] In this embodiment, a chlordecone solution, particularly at a concentration of up to 36 µg / ml, is percolated through a cartridge comprising 1 gram of molecularly imprinted polymer. Thus, 36 µg of chlordecone can be retained on the cartridge, per gram of polymer. This retention property proves the presence of the imprinting sites and can be used as a means of characterizing the polymer.

[0032] According to another particular embodiment, the present invention relates to a molecularly imprinted polymer as defined above, said molecularly imprinted polymer being in the form of a powder having a particle size of 25 to 40 µm.

[0033] By "25 to 40 µm » we also hear the following ranges: from 25 to 35 µm, from 25 to 30 µm, from 30 to 40 µm, from 35 to 40 µm, from 30 to 35 µm, in particular from 25 to 36 µm.

[0034] Particles of the particle size as defined above can be isolated by methods known to those skilled in the art, such as sieving and sedimentation.

[0035] Particles that are too fine, with a particle size that is too small, could pass through a frit positioned in the lower part of a cartridge containing the MIP. Furthermore, particles that are too fine make it difficult for the various solvents to pass through a cartridge containing the MIP, with a risk of clogging the cartridge.

[0036] Particles that are too large, with too high a particle size, have less accessibility to the imprint sites, compared to finer particles.

[0037] A second object of the present invention is a process for preparing a molecularly imprinted polymer, wherein the process comprises: a step A of polymerization of a monomer and a crosslinking agent, said polymerization step A being carried out in the presence of a porogen, a radical polymerization initiator, and chlordecol, wherein the monomer is selected from 4-vinylpyridine and 2-vinylpyridine, wherein the crosslinking agent is selected from ethylene glycol dimethacrylate (EGDMA), trimethylolpropane trimethacrylate (TRIM) and pentaerythritol triacrylate (PETRA), and wherein the porogen is acetonitrile or dichloromethane, to obtain a molecularly imprinted polymer containing chlordecol.

[0038] The invention relates to a process for preparing a molecularly imprinted polymer, wherein the process comprises: a step A of polymerization of a monomer and a crosslinking agent, said polymerization step A being carried out in the presence of a porogen, a radical polymerization initiator, and chlordecol, wherein the monomer is selected from 4-vinylpyridine and 2-vinylpyridine, wherein the crosslinking agent is selected from ethylene glycol dimethacrylate (EGDMA), trimethylolpropane trimethacrylate (TRIM) and pentaerythritol triacrylate (PETRA), wherein the porogen is acetonitrile or dichloromethane, and wherein the radical polymerization initiator is in particular AIBN, to obtain a molecularly imprinted polymer containing chlordecol.

[0039] The radical polymerization initiators that can be used in the present invention are any initiator known to initiate radical polymerization, including for example: 2,2,6,6-Tetramethyl-1-piperidinyloxy (TEMPO), azobisisobutyronitrile (AIBN), benzoyl peroxide (BPO), di-tert-butyl peroxide (TBP), tert-butyl peroxide (TBHP).

[0040] The porogen, or porogen solvent, acetonitrile or dichloromethane in the present invention, makes it possible to obtain a polymer with a porous structure. The imprint sites are thus accessible from the outside of the polymer through the pores formed by said porogen. The porogen therefore ensures access of chlordecone and / or chlordecol to the imprint sites.

[0041] The preparation of the molecularly imprinted polymers according to the present invention can be carried out in conventional laboratory or production equipment. Then, the product obtained can be dried to remove, or substantially remove, the pore-forming solvent. Molecular imprinting, to obtain a molecularly imprinted polymer, is schematically based on the steps shown in the Figure 1 .

[0042] Monomers, for example 4-vinylpyridine in the context of the present invention, are placed in the presence of the molecule to be printed (the imprint), for example chlordecol in the present invention ( Figure 1A ).

[0043] Said monomers interact reversibly with the imprint to form monomer-imprint complexes ( Figure 1B ).

[0044] Said monomer-imprint complexes then undergo copolymerization, during which the monomers are polymerized in the presence of a crosslinking agent, to obtain a three-dimensional polymer network ( Figure 1C ).

[0045] The imprint can then be removed from the polymer network to obtain the imprinted polymer itself, free of imprint, and having sites, or cavities, capable of receiving a molecule of similar structure, or of the same structure as the imprint used ( Figure 1D ). Thus, the molecularly imprinted polymers according to the present invention can accommodate both chlordecol and chlordecone.

[0046] Thus, according to a particular embodiment, the present invention relates to a preparation process as defined above, further comprising, after polymerization step A, a step B of removing chlordecol from the molecularly imprinted polymer, in particular by washing, to obtain said polymer free of chlordecol.

[0047] Removal step B can be carried out by washing, or rinsing, the polymer with a solvent capable of breaking the interactions between the chlordecol and the polymer, thus allowing the imprint to be removed.

[0048] The elimination of chlordecol can be demonstrated by analysis of the washing liquids, for example by LC / MS or GC / MS, and is considered complete when chlordecol is no longer detected in said washing liquids.

[0049] Step B of chlordecol removal is carried out in particular with a polar solvent, preferably protic, such as methanol, ethanol or isopropanol.

[0050] Removal step B is preferably carried out on a polymer in powder form. Indeed, at the end of step A, a product in the form of a "block" can be obtained, which complicates the handling of the product and in particular does not allow effective washing.

[0051] Under these conditions, the product from stage A of polymerization must be ground to ensure the “ powder » of the polymer.

[0052] Thus, according to another particular embodiment, the present invention therefore relates to a preparation process as defined above, comprising, between step A of polymerization, and step B of elimination of chlordecol, a step C of grinding, to obtain a ground molecularly imprinted polymer.

[0053] Grinding step C can be carried out with conventional equipment such as a mortar or a colloid mill type grinder.

[0054] According to a particular embodiment, the present invention relates to a preparation process as defined above, further comprising, after the grinding step C, a sieving step D, to obtain a sieved molecularly imprinted polymer, having in particular a particle size of 25 to 40 µm.

[0055] Sieving step D eliminates particles with a particle size greater than 40 µm and some of those less than 25 µm.

[0056] Particles larger than 40 µm remain in the 40 µm porosity sieve, while finer particles with a particle size smaller than 40 µm pass through the sieve mesh and onto the 25 µm porosity sieve. Particles larger than 25 µm remain on the 25 µm sieve and are collected.

[0057] Sieves suitable for sieving carried out in the method of the present invention are part of conventional laboratory equipment.

[0058] Sieving step D can be carried out before or after chlordecol removal step B, preferably after.

[0059] According to a particular embodiment, the present invention relates to a preparation process as defined above, further comprising, after sieving step D, a sedimentation step E, to obtain a sedimented molecularly imprinted polymer, in particular having a particle size of 25 to 40 µm.

[0060] Sedimentation step E allows the removal of particles " fines » , ie having a particle size of less than 25 µm, if they have not been completely eliminated during sieving step D. These fine particles remain in suspension and can be eliminated by decantation.

[0061] Sedimentation step E is carried out in a medium in which the polymer is not soluble, such as aqueous mixtures of alcohols such as methanol or ethanol, in particular in an alcohol / water ratio of approximately 80 / 20 v / v.

[0062] Sedimentation step E can be carried out before or after chlordecol removal step B.

[0063] According to another particular embodiment, the present invention relates to a preparation method as defined above, further comprising: after polymerization step A, a step B of removing chlordecol from the molecularly imprinted polymer, in particular by washing, to obtain said polymer free of chlordecol, said removal step B being carried out in particular with methanol, and optionally, between polymerization step A and chlordecol removal step B, a grinding step C, to obtain a ground molecularly imprinted polymer, and optionally after grinding step C, a sieving step D, to obtain a sieved molecularly imprinted polymer, in particular having a particle size of 25 to 40 µm, and optionally after sieving step D, a sedimentation step E, to obtain a sedimented molecularly imprinted polymer, in particular having a particle size of 25 to 40 µm, said sedimentation step E being carried out in particular with a methanol / water mixture, in particular in a ratio 80 / 20 v / v.

[0064] According to another particular embodiment, the present invention relates to a preparation process as defined above, in which the monomer is 4-vinylpyridine, and the porogen is acetonitrile.

[0065] According to another particular embodiment, the present invention relates to a preparation process as defined above, in which the monomer is 2-vinylpyridine, and the porogen is dichloromethane.

[0066] According to another particular embodiment, the present invention relates to a preparation process as defined above, in which the polymerization initiator used in polymerization step A is AIBN.

[0067] According to another particular embodiment, the present invention relates to a preparation process as defined above, in which the crosslinking agent used in polymerization step A is EGDMA.

[0068] According to another particular embodiment, the present invention relates to a preparation process as defined above, in which the monomer: crosslinking agent molar ratio used in polymerization step A is 3:30, preferably approximately 4:20.

[0069] Too low a monomer:crosslinker ratio leads to a decrease in the polymer retention capacity, while too high a ratio leads to a loss of retention selectivity.

[0070] According to another particular embodiment, the present invention relates to a preparation process as defined above, in which the molar ratio of chlordecol:monomer used in polymerization step A is 0.75:6, preferably approximately 1:4.

[0071] Too low a chlordecol:monomer ratio leads to a decrease in the polymer retention capacity, due to the formation of fewer imprint sites, while too high a ratio leads to a loss of selectivity.

[0072] According to another particular embodiment, the present invention relates to a preparation process as defined above, in which the molar ratio of chlordecol: crosslinking agent used in polymerization step A is 0.5:30, preferably approximately 1:20.

[0073] Too low a chlordecol:crosslinking agent ratio leads to a reduction in the polymer retention capacity, due to the formation of fewer imprint sites, while too high a ratio leads to a loss of selectivity.

[0074] According to another particular embodiment, the present invention relates to a preparation process as defined above, in which the ratio of chlordecol: monomer: crosslinking agent used in polymerization step A is approximately 1: 4: 20.

[0075] The inventors identified this ratio as being the most advantageous in terms of retention capacity and selectivity.

[0076] According to another particular embodiment, the present invention relates to a preparation process as defined above, in which the polymerization initiator is used at a rate of 1 mol% relative to the monomer.

[0077] According to another particular embodiment, the present invention relates to a preparation process as defined above, in which: the molar ratio of monomer: crosslinking agent used in polymerization step A is 3:30, preferably about 4:20, and / or the molar ratio of chlordecol: monomer used in polymerization step A is 0.75:6, preferably about 1:4, and / or the molar ratio of chlordecol: crosslinking agent used in polymerization step A is 0.5:30, preferably about 1:20, in particular, wherein the ratio of chlordecol: monomer: crosslinking agent used in polymerization step A is approximately 1:4:20.

[0078] According to another particular embodiment, the present invention relates to a preparation process as defined above, in which the polymerization step A is carried out either at a temperature of 50 to 54°C, in particular at a temperature of 54°C, the porogen being acetonitrile, or at a temperature of 25 to 30°C, the porogen being dichloromethane,

[0079] At too low a temperature, the low kinetics of the reaction are not compatible with an industrially reliable process. Too high a temperature leads to at least partial evaporation of the pore-forming solvent during synthesis, leading to solubility problems and / or non-homogeneous polymers.

[0080] According to another particular embodiment, the present invention relates to a preparation process as defined above, in which step B of removing chlordecol is carried out with methanol.

[0081] According to another particular embodiment, the present invention relates to a preparation process as defined above, in which the sedimentation step E is carried out with a methanol / water mixture, in particular in an 80 / 20 ratio.

[0082] According to another particular embodiment, the present invention relates to a preparation process as defined above, comprising: a step A of polymerization of 4-vinylpyridine and ethylene glycol dimethacrylate, in acetonitrile, in the presence of AIBN and chlordecol, to obtain a molecularly imprinted polymer containing chlordecol, a step C of grinding, to obtain a ground molecularly imprinted polymer, a step D of sieving, to obtain a sieved molecularly imprinted polymer, in particular having a particle size of less than 40 µm, a step E of sedimentation, to obtain a sedimented molecularly imprinted polymer, in particular having a particle size of 25 to 40 µm, and optionally a step B of removal of chlordecol from the molecularly imprinted polymer, in particular by methanol, to obtain said molecularly imprinted polymer free of chlordecol.

[0083] The optional chlordecol removal step B can be carried out before or after the screening step D or the sedimentation step E.

[0084] A third objectof the present invention is a molecularly imprinted polymer capable of being obtained by the process as defined above.

[0085] A fourth object of the present invention is the use of an imprinted polymer as defined above, for the purification of a sample comprising chlordecol and / or chlordecone.

[0086] The samples that can be purified within the scope of the present invention can be both solid samples once put into solution, or liquid samples.

[0087] Solid samples include: Soil samples, such as earth or sand.

[0088] Solid food samples, such as meat, fish, or fruits and vegetables.

[0089] Solid biological samples, such as tissues or hair.

[0090] Liquid samples include: Liquid biological samples, such as blood, serum, or urine.

[0091] Liquid food samples, such as milk or fruit juices.

[0092] Various aqueous samples, such as sea water, river water, rain water, lake water, groundwater (e.g., from the water table).

[0093] According to a particular embodiment, the present invention relates to the use as defined above, wherein the sample is a soil sample, an aqueous sample, a food sample or a biological sample.

[0094] A fourth object of the present invention is a cartridge comprising a molecularly imprinted polymer as defined above.

[0095] The cartridge may have a shape as visualized in the Figure 2(modified from https: / / fr.gilson.com / FRFR / learninghub / post / the-ins-and-outs-of-a-solid-phase-extraction-spe-workflow.html ), said cartridge being equipped, in its lower part, with a frit to prevent the polymer from leaving the cartridge with the flow of liquid.

[0096] Said frit having a porosity compatible with the particle size of the molecularly imprinted polymer contained therein, namely a porosity lower than said particle size.

[0097] A second frit is placed on the upper part of the cartridge, in order to allow the cartridge to be loaded with liquids, without damaging the surface of the polymer contained in the cartridge, but also " to block » the polymer in the cartridge.

[0098] The cartridge may contain a molecularly imprinted polymer without the imprint (chlordecol), or it may contain a molecularly imprinted polymer with the imprint still in place in the imprint sites.

[0099] In the latter case, the cartridge was loaded with a molecularly imprinted polymer which had not undergone step B of chlordecol removal as defined previously, and the imprint will first have to be removed, before use in a purification process as defined below.

[0100] In the following, the term "purification process" means a process for enriching a sample with chlordecone and / or chlordecol, compared to other components, or interferents, which may be present in the sample to be purified.

[0101] A fifth object of the present invention is a method of purifying a sample comprising chlordecone and / or chlordecol, which method comprises: a step 1 of percolation of said sample on a molecularly imprinted polymer as defined above, to obtain a molecularly imprinted polymer on which chlordecone and / or chlordecol is retained.

[0102] The invention relates to a method for purifying a sample comprising chlordecone and / or chlordecol, which method comprises: a step 1 of percolation of said sample on a molecularly imprinted polymer as defined above, in particular 4-VP MIP, to obtain a molecularly imprinted polymer on which chlordecone and / or chlordecol is retained, in which the sample to be percolated is in particular an aqueous sample, a food sample, a soil sample or a biological sample, said percolation step 1 is in particular carried out with acetonitrile or hexane or heptane.

[0103] In a particular embodiment, the invention relates to a method for purifying a sample comprising chlordecone and / or chlordecol, which method comprises: a step 1 of percolation of said sample on a molecularly imprinted polymer as defined above, in particular 4-VP MIP, to obtain a molecularly imprinted polymer on which chlordecone and / or chlordecol is retained, in which the sample to be percolated is in particular an organic extract of an aqueous sample, a food sample, a soil sample or a biological sample, said percolation step 1 is in particular carried out with acetonitrile, hexane or heptane and dichloromethane.

[0104] The percolation is carried out in particular on a cartridge as defined above, containing a molecularly imprinted polymer, by percolation of a solution comprising chlordecone and / or chlordecol through a molecularly imprinted polymer contained in said cartridge, as shown diagrammatically in the Figure 2 . Chlordecone and / or chlordecol is retained by the polymer thanks to the imprint sites.

[0105] The liquid recovered at the bottom of the cartridge, substantially free of chlordecone and / or chlordecol, is called, in the following, the “ percolation fraction(s). Similarly, the liquid recovered during the washing step is called the “wash fraction(s)”, or washing liquids, and the liquid recovered during the elution step is called the, or the “elution fraction(s)”, or eluate.

[0106] The percolation solvent, that is to say the solvent in which the sample to be purified has been previously solubilized, or diluted, is a solvent which does not elute chlordecone and / or chlordecol, in particular a non-protic solvent, in particular chosen from acetonitrile, hexane, heptane and dichloromethane.

[0107] The percolation solvent can be added in different ways, depending on the sample to be purified.

[0108] For example, a solid soil sample must be prepared and dissolved in the percolation solvent in order to extract chlordecone and / or chlordecol.

[0109] Conversely, a liquid sample, such as serum, may for example be diluted by the percolation solvent, then the percolation solvent comprising chlordecone and / or chlordecol may be separated by decantation, possibly, in the case of acetonitrile for example, after saturation of the aqueous phase by addition of salts, such as sodium chloride.

[0110] In the case where the addition of the percolation solvent to the sample to be purified leads to the formation of a precipitate, a centrifugation and / or filtration step can be implemented before percolation on the polymer. For example, in the case of serum, it is possible that proteins, insoluble in a solvent such as acetonitrile, may precipitate.

[0111] The sample to be purified may also undergo other pre-treatments known to those skilled in the art, such as for example the QuEChERS method for food-type samples.

[0112] According to a particular embodiment, the present invention relates to a purification method as defined above, further comprising, before percolation step 1: a step 0 of conditioning the molecularly imprinted polymer, to obtain a conditioned molecularly imprinted polymer.

[0113] In this embodiment, the polymer is brought into a usable condition.

[0114] According to a particular embodiment, conditioning step 0 is carried out with the solvent used during percolation step 1. This involves conditioning the cartridge with the solvent used during percolation step 1.

[0115] According to a particular embodiment, conditioning step 0 is carried out with hexane and percolation step 1 is carried out with heptane.

[0116] According to a particular embodiment, conditioning step 0 is carried out with heptane and percolation step 1 is carried out with hexane.

[0117] Advantageously, conditioning step 0 can be carried out with a solvent chosen from acetonitrile, hexane, heptane and dichloromethane.

[0118] The conditioning step allows the polymer to be equilibrated with the solvent to allow subsequent retention of chlordecone and / or chlordecol, and to prepare the imprint sites to promote retention of chlordecone and / or chlordecol.

[0119] According to another particular embodiment, the present invention relates to a purification method as defined above, further comprising, after percolation step 1: a step 2 of washing the molecularly imprinted polymer on which the chlordecone and / or chlordecol is percolated, to obtain a washed molecularly imprinted polymer.

[0120] Washing step 2 allows the total or partial removal of components other than chlordecone and / or chlordecol. Washing step 2 can be carried out by a single wash with a solvent or by a succession of at least two washes, with identical or different solvents.

[0121] According to another particular embodiment, the present invention relates to a purification method as defined above, in which washing step 2 is carried out with a single wash with a solvent.

[0122] According to another particular embodiment, the present invention relates to a purification method as defined above, in which washing step 2 is carried out with a succession of at least two washes, with identical or different solvents.

[0123] When different solvents are used, a drying step can be inserted between the two washing steps with different solvents. The drying step thus prevents the possible formation of an emulsion in the cartridge between immiscible solvents such as heptane and acetonitrile / methanol.

[0124] Advantageously, the drying step is carried out under vacuum or in air. Preferably, the drying step is carried out under air, for example by passing air over the cartridge. Drying under air has the advantage of being less time-consuming and is easier to implement.

[0125] According to another particular embodiment, the present invention relates to a purification method as defined above, in which washing step 2 comprises at least one drying step, preferably under air or under nitrogen.

[0126] According to another particular embodiment, the present invention relates to a purification method as defined above, further comprising, after washing step 2: a step 3 of elution of chlordecone and / or chlordecol, to obtain an eluate comprising chlordecone and / or chlordecol.

[0127] Thus, an eluate is obtained which is purified compared to the sample to be purified, deposited during percolation step 1. At least part of the impurities were eliminated during washing step 2.

[0128] The eluate obtained contains a higher “(chlordecone and / or chlordecol) / impurities” ratio compared to the sample to be purified.

[0129] Elution step 3 is carried out in particular with a polar solvent, preferably protic, such as methanol, ethanol or isopropanol.

[0130] According to another particular embodiment, the present invention relates to a purification method as defined above, further comprising, after elution step 3: step 4 detection of chlordecone and / or chlordecol by analysis of the eluate, in particular by LC / MS or by GC / MS.

[0131] Step 4 allows the presence of chlordecone and / or chlordecol to be detected in the eluate from elution step 3.

[0132] Quantification of chlordecone and / or chlordecol is also possible by processing the detection signal using methods known to those skilled in the art.

[0133] Thus, according to another particular embodiment, the present invention relates to a purification method as defined above, further comprising, after elution step 3: a step 4 of quantification of chlordecone and / or chlordecol by analysis of the eluate, in particular by LC / MS or by GC / MS.

[0134] According to another particular embodiment, the present invention relates to a purification process as defined above, in which the conditioning step 0 is carried out with acetonitrile, hexane or heptane.

[0135] According to another particular embodiment, the present invention relates to a purification process as defined above, in which percolation step 1 is carried out with acetonitrile, hexane or heptane.

[0136] According to another particular embodiment, the present invention relates to a purification process as defined above, in which washing step 2 is carried out with an acetonitrile / methanol mixture, in particular in a 95 / 5 ratio.

[0137] According to another particular embodiment, the present invention relates to a purification process as defined above, in which washing step 2 is carried out with a first wash with heptane followed by a drying step and a second wash with an acetonitrile / methanol mixture, in particular in a 95 / 5 ratio.

[0138] According to another particular embodiment, the present invention relates to a purification method as defined above, in which elution step 3 is carried out with methanol.

[0139] According to another particular embodiment, the present invention relates to a purification method as defined above, in which the sample to be percolated during step 1 is an aqueous sample, a food sample, a soil sample, or a biological sample.

[0140] According to another particular embodiment, the present invention relates to a purification method as defined above, further comprising: before percolation step 1, a conditioning step 0 of the molecularly imprinted polymer, in particular 4-VP MIP, to obtain a conditioned molecularly imprinted polymer, said conditioning step 0 being carried out in particular with acetonitrile or hexane or heptane, in particular with acetonitrile.and / or after percolation step 1, a step 2 of washing the molecularly imprinted polymer on which the chlordecone and / or chlordecol is percolated, to obtain a washed molecularly imprinted polymer, said washing step 2 being carried out in particular with an acetonitrile / methanol mixture, in particular in a 95 / 5 ratio, and optionally, after washing step 2, a step 3 of elution of the chlordecone, to obtain an eluate comprising the chlordecone and / or chlordecol, said elution step 3 being carried out in particular with methanol, and optionally, after elution step 3, a step 4 of detection of the chlordecone by analysis of the eluate, in particular by LC / MS or GC / MS.

[0141] According to another particular embodiment, the present invention relates to a purification method as defined above, further comprising: before percolation step 1, a conditioning step 0 of the molecularly imprinted polymer, in particular 4-VP MIP, to obtain a conditioned molecularly imprinted polymer, said conditioning step 0 being carried out in particular with acetonitrile or hexane or heptane, in particular in heptane.and / or after percolation step 1, a step 2 of washing the molecularly imprinted polymer on which the chlordecone and / or chlordecol is percolated, to obtain a washed molecularly imprinted polymer, said washing step 2 being carried out in particular with a first wash with heptane followed by a drying step and a second wash with an acetonitrile / methanol mixture, in particular in a 95 / 5 ratio, and optionally, after washing step 2, a step 3 of elution of the chlordecone, to obtain an eluate comprising the chlordecone and / or chlordecol, said elution step 3 being carried out in particular with methanol, and optionally, after elution step 3, a step 4 of detection of the chlordecone by analysis of the eluate, in particular by LC / MS or LC / MS / MS or GC / MS or GC / MS / MS.

[0142] According to another particular embodiment, the present invention relates to a purification method as defined above, comprising the following steps: a step 0 of conditioning the molecularly imprinted polymer, in particular 4-VP MIP, in particular with acetonitrile or hexane or heptane, to obtain a conditioned molecularly imprinted polymer, a step 1 of percolating said sample on said conditioned molecularly imprinted polymer, in particular in acetonitrile or hexane or heptane, to obtain a molecularly imprinted polymer on which chlordecone and / or chlordecol is retained, a step 2 of washing the molecularly imprinted polymer on which chlordecone and / or chlordecol is retained, in particular with a 95 / 5 acetonitrile / methanol mixture, to obtain a washed molecularly imprinted polymer, and a step 3 of elution of the chlordecone and / or chlordecol, in particular with methanol, to obtain an eluate comprising chlordecone and / or chlordecol chlordecol.

[0143] According to another particular embodiment, the present invention relates to a purification method as defined above, comprising the following steps: a step 0 of conditioning the molecularly imprinted polymer, in particular 4-VP MIP, in particular with acetonitrile, to obtain a conditioned molecularly imprinted polymer, a step 1 of percolating said sample on said conditioned molecularly imprinted polymer, in particular in acetonitrile, to obtain a molecularly imprinted polymer on which chlordecone and / or chlordecol is retained, a step 2 of washing the molecularly imprinted polymer on which chlordecone and / or chlordecol is retained, in particular with a 95 / 5 acetonitrile / methanol mixture, to obtain a washed molecularly imprinted polymer, and a step 3 of elution of the chlordecone and / or chlordecol, in particular with methanol, to obtain an eluate comprising chlordecone and / or chlordecol.

[0144] According to another particular embodiment, the present invention relates to a purification method as defined above, comprising the following steps: a step 0 of conditioning the molecularly imprinted polymer, in particular 4-VP MIP, in particular with acetonitrile or hexane or heptane, to obtain a conditioned molecularly imprinted polymer, a step 1 of percolation of said sample on said conditioned molecularly imprinted polymer, in particular in hexane or heptane, to obtain a molecularly imprinted polymer on which chlordecone and / or chlordecol is retained, a step 2 of washing the molecularly imprinted polymer on which chlordecone and / or chlordecol is retained, in particular by a first wash with heptane or hexane followed by a drying step and a second wash with an acetonitrile / methanol mixture, in particular in a 95 / 5 ratio, to obtain a washed molecularly imprinted polymer, and a step 3 of elution of the chlordecone and / or chlordecol, in particular with methanol, to obtain an eluate comprising chlordecone and / or chlordecol.

[0145] According to another particular embodiment, the present invention relates to a purification method as defined above, comprising the following steps: a step 0 of conditioning the molecularly imprinted polymer, in particular 4-VP MIP, in particular with hexane or heptane, in particular heptane, to obtain a conditioned molecularly imprinted polymer, a step 1 of percolation of said sample on said conditioned molecularly imprinted polymer, in particular in acetonitrile, to obtain a molecularly imprinted polymer on which chlordecone and / or chlordecol is retained, a step 2 of washing the molecularly imprinted polymer on which chlordecone and / or chlordecol is retained, in particular by a first wash with heptane followed by a drying step and a second wash with an acetonitrile / methanol mixture, in particular in a 95 / 5 ratio, to obtain a washed molecularly imprinted polymer, and a step 3 of elution of the chlordecone and / or chlordecol, in particular with methanol, to obtain a eluate comprising chlordecone and / or chlordecol.

[0146] According to another particular embodiment, the present invention relates to a purification method as defined above, comprising the following steps: a step 0 of conditioning the molecularly imprinted polymer, in particular 4-VP MIP, in particular with hexane or heptane, in particular heptane, to obtain a conditioned molecularly imprinted polymer, a step 1 of percolating said sample on said conditioned molecularly imprinted polymer, in particular in hexane or heptane, in particular in heptane, to obtain a molecularly imprinted polymer on which chlordecone and / or chlordecol is retained, a step 2 of washing the molecularly imprinted polymer on which chlordecone and / or chlordecol is retained, in particular by a first wash with heptane followed by a drying step and a second wash with an acetonitrile / methanol mixture, in particular in a 95 / 5 ratio, to obtain a washed molecularly imprinted polymer, and a step 3 of elution of the chlordecone and / or chlordecol, especially with methanol,to obtain an eluate comprising chlordecone and / or chlordecol.,

[0147] The following examples and figures illustrate the invention, without limiting its scope. There Figure 1 represents the general principle of molecularly imprinted polymers. A represents the different reactants; the monomers 1 the crosslinking agent 2, and the imprint 3. B represents the interactions between the monomers and the imprint, before polymerization. C represents the polymerization of monomers around the imprint and D represents the release of cavities by washing the imprint. Figure 2 represents the general principle of using a MIP in the purification of a sample. 0 represents conditioning step 0, 1 represents percolation step 1, 2 represents washing step 2, and 3represents elution step 3, • represents the analytes, chlordecone and / or chlordecol in the present invention, ▲ ●■ represent the interferents, namely the compounds other than chlordecone and / or chlordecol in the present invention. The Figure 3 represents the LC / MS profile obtained with the analytical method of example A. The Figure 4 represents the extraction yield for the chlordecone present in the different fractions obtained in Example 3. The dark bars represent the amount of chlordecone using MIPs, and the light bars represent the amount of chlordecone using NIPs. P represents the percolation fractions, L represents the wash fractions, and E represents the elution fractions. The Figure 5 represents the extraction yield for the chlordecolpresent in the different fractions obtained in Example 3. The dark bars represent the amount of chlordecol using MIPs, and the light bars represent the amount of chlordecol using NIPs. P represents the percolation fractions, L represents the wash fractions, and E represents the elution fractions. The Figure 6 represents the extraction yield for the chlordecone present in the elution fraction (E) obtained in example 6 from an extract of salmon In hexane. The dark bar represents the yield of chlordecone using MIPs, and the light bar represents the yield of chlordecone using NIPs. Figure 7 represents the extraction yield for the chlordecone present in the elution fraction (E) obtained in example 6 from an extract of tomato in the hexaneThe dark bar represents the yield of chlordecone using MIPs, and the light bar represents the yield of chlordecone using NIPs. Figure 8 represents the yield of chlordecone present in the elution fraction (E) obtained in example 6 from an extract of salmon in the acetonitrile. The dark bar represents the yield of chlordecone using MIPs, and the light bar represents the yield of chlordecone using NIPs. Figure 9 represents the yield of chlordecone present in the elution fraction (E) obtained in example 6 from an extract of tomato in the acetonitrile. The dark bar represents the yield of chlordecone using MIPs, and the light bar represents the yield of chlordecone using NIPs. EXAMPLES Example A - Analytical detection method

[0148] Detection and quantification of chlordecone and chlordecol in the samples were performed by LC / MS, under the conditions in Table 1. Tableau 1 conditions LC / MS Chromatographic conditions Column Atlantis C18 5 µm, 2.1 x 150 mm Column temperature 40°C Mobile Phase A / Water + 0.1% Formic Acid (AF) B / ACN + 0.1% AF Isocratic mode: 40% A / 60% B Speed 300 µL / min Injection volume 5 µL Mass spectrometer settings Device Triple quadrupole (Agilent) Source ESI in negative mode Temperature 340°C Gas flow rate 10 l / min Nebulizer 45 psi Capillary tension 3000 V Acceleration cell voltage 3 V Example 1 - Preparation of a molecularly imprinted polymer (MIP)

[0149] In a glass vial, chlordecol (1 mmol) and 4-vinylpyridine (4 mmol) were mixed in acetonitrile (1.8 ml) and the mixture was placed in an ultrasonic bath. After 10 minutes of sonication, ethylene glycol dimethacrylate (20 mmol) was added, and then the mixture was purged for 10 minutes with a stream of N 2 to remove dissolved oxygen. AIBN (0.2 mmol) was added to the reaction mixture and the glass vial was tightly sealed and placed in a water bath at 60 °C for 24 hours. The vials were then broken, and the resulting polymer was ground and sieved, and particles with sizes between 25 and 36 µm were collected.

[0150] A sedimentation step with 4 x 5 mL of a methanol / water mixture 80 / 20 v / v was carried out to remove the finest particles, and the particles with a particle size of 25 to 40 µm were placed in a cartridge between 2 frits to be used as a solid phase extraction support. Thus, cartridges containing 35 mg of MIP were prepared.

[0151] The MIP thus contained in the cartridges still contains the imprint, namely the chlordecol, which was eliminated by passing through methanol, prior to use in the examples below. Example 2 - Preparation of a polymer without molecular imprints (NIP)

[0152] A non-imprinted support (NIP) was synthesized under the same conditions as used in Example 1, but without introducing chlordecol into the reaction mixture. Example 3 - Characterization of the MIP

[0153] The MIP (35 mg), contained in a cartridge, obtained according to example 1 was conditioned by passing 1 ml of acetonitrile (conditioning step 0). Then, a solution of 1 mL of chlordecone (CLD) at 0.2 µg / mL and chlordecol (CLDOH) at 0.2 µg / mL in acetonitrile was percolated onto the MIP, by passing said solution onto the cartridge (percolation step 1).

[0154] The MIP was then washed with 1.5 mL of a 95 / 5, v / v, acetonitrile / methanol mixture (washing step 2). Finally, chlordecone and chlordecol were eluted by passing 3 mL of methanol (elution step 3).

[0155] The same procedure was implemented on a PIN, obtained according to example 2.

[0156] The experiments on the MIP and on the NIP were carried out 3 times on 3 cartridges from 3 different batches of MIP and NIP.

[0157] For each of the experiments, the conditioning, percolation, washing, and elution fractions, recovered at the bottom of the cartridges, were analyzed by the LC / MS procedure of example A. Thus, the quantity of chlordecone and chlordecol, present in the different fractions was determined and the average of the results was calculated over the 3 experiments (MIP and NIP).

[0158] There Figure 4 shows the results obtained for chlordecone. The percolation step allows the retention, on the MIP, of all the chlordecone contained in the percolated sample. During the washing step, only 8% of chlordecone is washed from the cartridge, in the case of MIP, while the majority of chlordecone is washed out in the case of NIP. These results show that MIP has the ability to retain chlordecone, compared to the NIP which does not retain this product. The elution step then allows the chlordecone retained on the MIP to be recovered.

[0159] There Figure 5shows the results obtained for chlordecol, which is more retained on the MIP than on the NIP. Example 4 - Purification / detection of a commercial bovine serum sample (sigma Aldrich)

[0160] After sample collection, 1.5 mL of serum was treated with 4.5 mL of acetonitrile (protein precipitation). 4 mL of water was added to the resulting supernatant. Salts (QuEChERS Extraction Packets, composed of 4 g of anhydrous magnesium sulfate, 1 g of sodium chloride, 1 g of trisodium citrate dihydrate, and 0.5 g of disodium dihydrogen citrate sesquihydrate), allowing the transfer of chlordecone to the acetonitrile phase, were added.

[0161] The MIP conditioning, percolation, washing and elution steps were carried out on a cartridge according to Example 1, and using the procedure of Example 3. An LC / MS analysis of the different fractions shows that for chlordecone, no loss is observed during conditioning, a loss of 8% is observed during washing, and that 81% of the chlordecone is recovered during elution on the MIP.

[0162] This analysis shows that for chlordecone, 3% loss is observed during percolation, a loss of 62% is observed during washing, and that only 23% of the chlordecone is recovered during elution on the unprinted polymer.

[0163] This demonstrates the specificity of MIP with respect to chlordecone. Example 5 - Purification / detection of a food sample

[0164] For a food sample, 5g of ground sample are taken, to which 10 mL of ultrapure water and 10 mL of acetonitrile are added. After stirring, and addition of salts composed of 4g of anhydrous magnesium sulfate, 1g of sodium chloride, 1g of trisodium citrate dihydrate, and 0.5g of disodium dihydrogen citrate sesquihydrate, the acetonitrile phase is percolated on the support according to example 1. A specificity of the MIP with respect to chlordecone and chlordecol is observed. Example 6 - Purification / detection of a salmon food sample in hexane

[0165] To prepare salmon extract in hexane by Liquid-Liquid Extraction (LLE), salmon was ground using a Grindomix knife grinder-mixer for 30 seconds at 7000 rpm.

[0166] A 5 gram sample is weighed into a 50 mL centrifuge tube, then 10 mL of hexane is added and the tube is then vortexed for 10 min and then centrifuged for 5 min at 4000 rpm. The supernatant is removed and filtered to obtain the extract.

[0167] A chlordecone (CLD) spiking at 20 µg.kg - 1< is carried out in the filtrate. The spiking before the SPE allows to evaluate the contribution of MIP 4-VP on the extraction of CLD from the sample. The introduced quantity of CLD serves as a reference (100%) and the entire experimental extraction yield obtained is calculated from this quantity.

[0168] The MIP (35 mg), contained in a cartridge, obtained according to example 1 was conditioned by passing 1 mL of hexane (conditioning step 0). Then, a solution of 1 mL of salmon extract in hexane doped with chlordecone (CLD) was percolated onto the MIP, by passing said solution onto the cartridge (percolation step 1).

[0169] The MIP was then washed with 300 µL of heptane, air-dried with approximately 20 mL, and then washed with 1 mL of acetonitrile / methanol mixture, 95 / 5, v / v (wash step 2). Finally, chlordecone was eluted by passing 3 mL of methanol (elution step 3).

[0170] The same procedure was implemented on a PIN, obtained according to example 2.

[0171] The overall procedure, namely LLE extraction, conditioning step 0, percolation step 1, washing step 2, elution step 3 and detection step 4 was performed 3 times on the MIP, and on the NIP. The experiments were carried out on 3 cartridges from 3 different batches of MIP and NIP. To avoid any bias, the same volume of solvent was percolated through the control medium (NIP).

[0172] For each experiment, only the elution fraction (E), recovered at the bottom of the cartridges, was analyzed by the LC / MS procedure. Thus, the amount of chlordecone present in the elution fraction was determined and the average of the results was calculated over the 3 experiments (MIP and NIP).

[0173] There Figure 6 shows the results obtained for chlordecone in a food matrix of salmon extracted in hexane.

[0174] The percolation step allows the retention, on the MIP, of all the chlordecone contained in the percolated sample. Indeed, the elution step then allows the recovery of all the chlordecone retained on the MIP (estimated CLD yield in the eluate of 116 ±8%). These results show that MIP has the ability to retain chlordecone in a hexane-extracted salmon food sample and to release it by elution, compared to the NIP which does not retain this product (7%). The selectivity of the MIP towards chlordecone is maintained in real environment with a salmon extract in hexane. Example 7- Purification / detection of a food sample of tomato in hexane

[0175] The same protocol as example 6 was carried out with a food sample, a tomato matrix.

[0176] There Figure 7 shows the results obtained for chlordecone in a food matrix of tomato extracted in hexane. The percolation step allows the retention, on the MIP, of all the chlordecone contained in the percolated sample. Indeed, the elution step then allows the recovery of the chlordecone retained on the MIP with an estimated CLD yield in the eluate of 116%. These results show that MIP has the ability to retain chlordecone in a tomato food sample extract and to release it by elution, compared to the NIP which does not retain this product (10%). The selectivity of the MIP towards chlordecone is maintained in real medium with a tomato extract in hexane. Example 8 - Purification / detection of a salmon food sample in acetonitrile

[0177] To prepare salmon extract in hexane by Liquid-Liquid Extraction (LLE), salmon was ground using a Grindomix knife grinder-mixer for 30 seconds at 7000 rpm.

[0178] A 5 gram sample is weighed into a 50 mL centrifuge tube, then 10 mL of ultrapure water and 10 mL of acetonitrile are added, and the tube is then vortexed for 10 min and then centrifuged for 5 min at 4000 rpm. The supernatant is removed and filtered. A spike of CLD at 20 µg.kg - 1< is carried out in the filtrate.

[0179] The MIP (35 mg), contained in a cartridge, obtained according to example 1 was conditioned by passing 1 ml of hexane (conditioning step 0). Then, a solution of 1 ml of salmon extract in acetonitrile doped with chlordecone (CLD) was percolated onto the MIP, by passing said solution onto the cartridge (percolation step 1).

[0180] The MIP was then washed with 300 µL of heptane (L1), air-dried with approximately 20 mL, and then washed with 1 mL of acetonitrile / methanol mixture, 95 / 5, v / v (washing step 2). Finally, chlordecone was eluted by passing 3 mL of methanol (elution step 3).

[0181] The same procedure was implemented on a PIN, obtained according to example 2.

[0182] The overall procedure, namely LLE extraction, conditioning step 0, percolation step 1, washing step 2, elution step 3 and detection step 4 was performed 3 times on the MIP, and on the NIP. The experiments were carried out on 3 cartridges from 3 different batches of MIP and NIP. To avoid any bias, the same volume of solvent was percolated through the control medium (NIP).

[0183] For each experiment, only the elution fraction (E), recovered at the bottom of the cartridges, was analyzed by the LC / MS procedure. Thus, the amount of chlordecone present in the elution fraction was determined and the average of the results was calculated over the 3 experiments (MIP and NIP).

[0184] There Figure 8 shows the results obtained for chlordecone in a food matrix of salmon extracted in acetonitrile. The elution step then allows the recovery of the chlordecone retained on the MIP with an estimated CLD yield in the eluate of 143%. These results show that MIP has the ability to retain chlordecone in a salmon food sample extract and to release it by elution, compared to the NIP which does not retain this product (7%).

[0185] Selectivity is maintained in real medium with a salmon extract in acetonitrile.

[0186] Given the complexity of the sample (sample rich in lipids and proteins), yields greater than 100% are observed. A matrix effect during electrospray ionization during LC / MS analysis tends to overestimate the measured concentrations. Example 9 - Purification / detection of a tomato food sample in acetonitrile

[0187] The same protocol as in example 8 was carried out with a tomato matrix as a food sample.

[0188] There Figure 9 shows the results obtained for chlordecone in a food matrix of tomato extracted in acetonitrile. The elution step then allows the recovery of the chlordecone retained on the MIP with an estimated CLD yield in the eluate of 157%. These results show that MIP has the ability to retain chlordecone in a tomato food sample extract and to release it by elution, compared to the PIN which does not retain this product (10%).

[0189] The selectivity of MIP is maintained in real medium with a tomato extract in acetonitrile.

Claims

1. Molecularly imprinted polymer (MIP) wherein the polymer is poly-4-vinylpyridine, or poly-2-vinylpyridine, crosslinked by a crosslinking agent, wherein the crosslinking agent is selected from ethylene glycol dimethacrylate (EGDMA), trimethylolpropane trimethacrylate (TRIM) and pentaerythritol triacrylate (PETRA), said molecularly imprinted polymer containing imprint sites for chlordecol and / or chlordecone, in particular wherein the polymer is poly-4-vinylpyridine (4-VP MIP) crosslinked with ethylene glycol dimethacrylate (EGDMA).

2. A molecularly imprinted polymer according to claim 1, wherein the polymer is poly-4-vinylpyridine, crosslinked by a crosslinking agent, wherein the crosslinking agent is selected from ethylene glycol dimethacrylate (EGDMA), trimethylolpropane trimethacrylate (TRIM) and pentaerythritol triacrylate (PETRA), said molecularly imprinted polymer containing imprint sites for chlordecol and / or chlordecone.

3. A molecularly imprinted polymer according to one of claims 1 or 2, said molecularly imprinted polymer having a chlordecone retention capacity, determined by LC / MS, at a rate of 36 µg per gram of polymer.

4. A method of preparation of a molecularly imprinted polymer, wherein the method comprises: • a step A of polymerization of a monomer and a crosslinking agent, said step A of polymerization being carried out in the presence of a porogen, a radical polymerization initiator, and chlordecol, wherein the monomer is selected from 4-vinylpyridine and 2-vinylpyridine, wherein the crosslinking agent is selected from ethylene glycol dimethacrylate (EGDMA), trimethylolpropane trimethacrylate (TRIM) and pentaerythritol triacrylate (PETRA), wherein the porogen is acetonitrile or dichloromethane, and wherein the radical polymerization initiator is in particular AIBN, to obtain a molecularly imprinted polymer containing chlordecol.

5. The method of preparation according to claim 4, further comprising: after the step A of polymerization, a step B of removal chlordecol from the molecularly imprinted polymer, in particular by washing, to obtain said polymer free of chlordecol, said step B of removing being carried out in particular with methanol, and optionally between the step A of polymerization and the step B of removal chlordecol, a grinding step C, to obtain a ground molecularly imprinted polymer, and optionally after the grinding step C, a sieving step D, to obtain a sieved molecularly imprinted polymer, in particular having a particle size from 25 to 40 µm, and optionally after the sieving step D, a sedimentation step E, to obtain a sedimented molecularly imprinted polymer, in particular having a particle size from 25 to 40 µm, said sedimentation step E being carried out in particular with a methanol / water mixture, in particular in a ratio 80 / 20, preferably wherein the monomer is 4-vinylpyridine and the porogen is acetonitrile.

6. The method of preparation according to one of claims 4 to 5, wherein : • the molar ratio of monomer : crosslinking agent used in the step A of polymerization is in the range 3 : 30, preferably about 4 : 20, and / or • the molar ratio of chlordecol : monomer used in the step A of polymerization is 0.75 : 6, preferably about 1 : 4, and / or • the molar ratio of chlordecol : crosslinking agent used in the step A of polymerization is in the range 0.5 : 30, preferably about 1 : 20, in particular, wherein the ratio of chlordecol : monomer : crosslinking agent used in the step A pf polymerization is about 1 : 4 : 20, in particular wherein the step A of polymerization is carried out : either at a temperature from 50 to 54°C, in particular at 54°C, the porogen being acetonitrile, or at a temperature from 25 to 30°C, the porogen being dichloromethane.

7. The method of preparation according to any one of claims 4 to 6, comprising : • a step A of polymerization of 4-vinylpyridine and ethylene glycol dimethacrylate, in acetonitrile, in the presence of AIBN and chlordecol, to obtain a molecularly imprinted polymer containing chlordecol, • a grinding step C, to obtain a ground molecularly imprinted polymer, • a sieving step D, to obtain a sieved molecularly imprinted polymer, in particular having a particle size of less than 40 µm, • a sedimentation step E, to obtain a sedimented molecularly imprinted polymer, in particular having a particle size of 25 to 40 µm, and • optionally, a step B of removal chlordecol from the molecularly imprinted polymer, in particular using methanol, to obtain said molecularly imprinted polymer free of chlordecol.

8. Molecularly imprinted polymer obtainable by the method according to any one of claims 4 to 7.

9. Use of an imprinted polymer according to any one of claims 1, 2, 3 or 8, for the purification of a sample comprising chlordecol and / or chlordecone, wherein the sample is in particular a soil sample, an aqueous sample, a food sample or a biological sample.

10. A cartridge comprising a molecularly imprinted polymer according to any one of claims 1, 2, 3 or 8.

11. A method of purification of a sample comprising chlordecone and / or chlordecol, said method comprises: • a step 1 of percolation of said sample on a molecularly imprinted polymer, according to one of claims 1, 2, 3 or 8, in particular 4-VP MIP, to obtain a molecularly imprinted polymer on which chlordecone and / or chlordecol is retained, wherein the sample to be percolated is in particular an aqueous sample, a food sample, a soil sample or a biological sample, said step 1 of percolation is carried out using acetonitrile, hexane or heptane.

12. The method of purification according to claim 11, further comprising: • prior to the step 1 of percolation, a step 0 of conditioning, of the molecularly imprinted polymer, in particular 4-VP MIP, to obtain a conditioned molecularly imprinted polymer, said step 0 of conditioning being carried out in particular with acetonitrile or hexane or heptane, and / or • after the step 1 of percolation, a step 2 of washing the molecularly imprinted polymer onto which the chlordecone and / or chlordecol has been percolated, to obtain a washed molecularly imprinted polymer, said step 2 of washing being carried out in particular with an acetonitrile / methanol mixture, in particular in a 95 / 5 ratio, and optionally • after the step 2 of washing, a step 3 of elution of chlordecone, to obtain an eluate comprising chlordecone and / or chlordecol, said step 3 of elution being carried out in particular with methanol, and optionally • after the step 3 of elution, a step 4 of chlordecone detection by analysis of the eluate, in particular by LC / MS or GC / MS.

13. The method of purification according to claim 11, further comprising: • prior to the step 1 of percolation, a step 0 of conditioning, of the molecularly imprinted polymer, in particular 4-VP MIP, to obtain a conditioned molecularly imprinted polymer, said step 0 of conditioning being carried out in particular with acetonitrile or hexane or heptane, and / or • after the step 1 of percolation, a step 2 of washing the molecularly imprinted polymer onto which the chlordecone and / or chlordecol has been percolated, to obtain a washed molecularly imprinted polymer, said step 2 of washing being carried out in particular with a first wash with heptane followed by a drying step and a second wash with an acetonitrile / methanol mixture, in particular in a ratio 95 / 5, and optionally • after the step 2 of washing, a step 3 of elution of chlordecone, to obtain an eluate comprising chlordecone and / or chlordecol, said step 3 of elution being carried out in particular with methanol, and optionally • after the elution step 3, a chlordecone detection step 4 by analysis of the eluate, in particular by LC / MS or GC / MS.

14. The method of purification according to one of claims 11 or 12, comprising the following steps: • a step 0 of conditioning the molecularly imprinted polymer, in particular 4-VP MIP, in particular with acetonitrile or hexane or heptane, to obtain a conditioned molecularly imprinted polymer, • a step 1 of percolation of said sample onto said conditioned molecularly imprinted polymer, notably dissolved in acetonitrile or hexane or heptane, to obtain a molecularly imprinted polymer on which chlordecone and / or chlordecol is retained, • a step 2 of washing the molecularly imprinted polymer on which the chlordecone and / or chlordecol is retained, in particular with an acetonitrile / methanol 95 / 5 mixture, to obtain a washed molecularly imprinted polymer, and • a step 3 of elution of chlordecone and / or chlordecol, to obtain an eluate comprising chlordecone and / or chlordecol.

15. Methode of purification according to any one of claims 11 or 13, comprising the following steps: • a step 0 of conditioning the molecularly imprinted polymer, in particular 4-VP MIP, in particular with acetonitrile or hexane or heptane, to obtain a conditioned molecularly imprinted polymer, • a step 1 of percolation of said sample onto said conditioned molecularly imprinted polymer, notably dissolved in acetonitrile or hexane or heptane, to obtain a molecularly imprinted polymer on which chlordecone and / or chlordecol is retained, • a step 2 of washing the molecularly imprinted polymer on which the chlordecone and / or chlordecol is retained, in particular by a first wash with heptane followed by a drying step and a second wash with an acetonitrile / methanol mixture, in particular in a 95 / 5 ratio, to obtain a washed molecularly imprinted polymer, and • a step 3 of elution of chlordecone and / or chlordecol, to obtain an eluate comprising chlordecone and / or chlordecol.