Method for decontaminating an aqueous liquid medium containing micropollutants or a surface contaminated with micropollutants

Abstract

The invention relates to a method for decontaminating an aqueous liquid medium containing molecular micropollutants or a surface contaminated with micropollutants using nucleolipid compounds.

Claims

1. Method for decontaminating an aqueous liquid medium containing at least one micropollutant in molecular form, or a surface contaminated with a micropollutant, comprising a step of contacting said aqueous liquid medium containing said at least one micropollutant in molecular form or said surface contaminated with said at least one micropollutant with at least one nucleolipid compound of formula (I) ##STR00006## in which X is an atom of oxygen, sulfur or a methylene group B represents a purine or pyrimidine base, or also a non-natural heterocyclic mono- or bicyclic base, each ring of which comprises 4 to 7 members, optionally substituted; L.sub.1 and L.sub.2, identical or different, represent hydrogen, an —O—C(O)— oxycarbonyl group, an —O—C(S)—NH— thiocarbamate group, an —O—C(O)—O— carbonate group, an —O—C(O)—NH— carbamate group, an oxygen atom, a phosphate group, a phosphonate group or a heteroaryl group comprising from 1 to 4 nitrogen atoms, substituted or unsubstituted by a saturated or unsaturated, linear or branched C.sub.8-C.sub.30 hydrocarbon chain; where L.sub.1 represents a phosphate or phosphonate group and L.sub.2 represents hydrogen; or also, L.sub.1 and L.sub.2 together form a ketal group of formula ##STR00007## or also L.sub.1 or L.sub.2 represents hydrogen, and the other represents a hydroxy group or a heteroaryl group comprising 1 to 4 nitrogen atoms, unsubstituted or substituted by a linear or branched C.sub.8-C.sub.30 alkyl chain; R.sub.1 and R.sub.2, identical or different, represent: a linear or branched C.sub.8-C.sub.30 hydrocarbon chain, saturated or comprising one or more unsaturations, a C.sub.8-C.sub.30 acyl chain, a diacyl chain in which each acyl chain is C.sub.8-C.sub.30, a diacylglycerol chain in which each acyl chain is C.sub.8-C.sub.30, a sphingosine or ceramide group, or when L.sub.1 or L.sub.2 represents hydrogen, and the other represents a hydroxy group or a heteroaryl group comprising 1 to 4 nitrogen atoms, R.sub.1 and R.sub.2 are not present; R.sub.3 represents: a hydroxy, amino, phosphate, phosphonate, phosphatidylcholine, O-alkyl phosphatidylcholine, thiophosphate, phosphonium, NH.sub.2—R.sub.4, NHR.sub.4R.sub.5 or NR.sub.4R.sub.5R.sub.6 group in which R.sub.4, R.sub.5 and R.sub.6, identical or different, represent a hydrogen atom or a linear or branched C.sub.1-C.sub.6 alkyl or linear or branched C.sub.1-C.sub.6 hydroxyalkyl chain, or a linear or branched C.sub.2-C.sub.30 alkyl chain, optionally substituted by a hydroxy group, or a heteroaryl group containing 1 to 4 nitrogen atoms, unsubstituted or substituted by a C.sub.2-C.sub.30 alkyl, or by a (CH.sub.2).sub.m—O—(CH.sub.2).sub.p—R.sub.9 group in which m=1 to 6 and p=0 to 20 and R.sub.9 represents hydrogen or a cyclic ketal group containing 5 to 7 carbon atoms, unsubstituted or substituted by at least one linear or branched C.sub.2-C.sub.30 alkyl, or by a sterol residue, or also R.sub.3 is linked by covalent bonding to another R.sub.3 substituent, identical or different, of another compound of formula (I), identical or different, to form a compound of formula (I) in dimer form, and a step of separating the aggregate formed by said at least one micropollutant in molecular form with said at least one nucleolipid compound of formula (I) in said aqueous liquid medium or the aggregate formed by said at least one micropollutant with said at least one nucleolipid compound of formula (I) on said surface.

2. Method according to claim 1, in which the contacting step is a step of contacting an aqueous liquid medium containing at least one micropollutant in molecular form with at least one nucleolipid compound of formula (I) as defined in claim 1, and the separation step is a step of separating the aggregate formed by said micropollutant in molecular form with said at least one nucleolipid compound of formula (I).

3. Method according to claim 1, in which the contacting step is a step of contacting said surface contaminated with at least one micropollutant with at least one nucleolipid compound of formula (I) as defined in claim 1, and the separation step is a step of separating the aggregate formed by said at least one micropollutant with said at least one nucleolipid compound of formula (I) on said surface.

4. Method according to claim 1, in which a single compound of formula (I) is used.

5. Method according to claim 1, in which 2 or more than 2 different compounds of formula (I) are used simultaneously or sequentially.

6. Method according to claim 1, comprising a step of contacting said aqueous liquid medium containing at least one micropollutant in molecular form or said surface contaminated with at least one micropollutant with at least one nucleolipid compound of formula (I), a step of incubating said aqueous liquid medium containing at least one micropollutant in molecular form or said surface contaminated with a micropollutant with at least one nucleolipid compound of formula (I), and a step of separating the aggregate formed by said micropollutant in molecular form with said at least one nucleolipid compound of formula (I) in said aqueous liquid medium or the aggregate formed by said micropollutant with said at least one nucleolipid compound of formula (I) on said surface.

7. Method according to claim 1, in which contacting is carried out by dissolution or dispersion of the nucleolipid compound of formula (I) in the aqueous medium, by application on the contaminated surface of a solution or a suspension of nucleolipid compound of formula (I) in a suitable solvent such as water or an organic solvent, or by application on said contaminated surface of a powder comprising the nucleolipid compound of formula (I) or constituted by the nucleolipid compound of formula (I).

8. Method according to claim 1, in which said micropollutant in molecular form meets at least one of the following conditions: it is constituted by a single molecule; one of its dimensions is less than 0.5 nm; it has a nominal diameter less than 0.5 nm; it has a molar mass comprised between 60 g/mol and 5000 g/mol, preferably between 100 g/mol and 1000 g/mol; it is an organic molecule.

9. Method according to claim 1, in which, in formula (I), B represents a purine or pyrimidine base selected from adenine, guanine, cytosine, xanthine, hypoxanthine, uric acid, caffeine, theobromine, uracil, thymine, dihydrouridine, and derivatives thereof, preferably thymine or uracil.

10. Method according to claim 1, in which at least one compound of formula (I) is used in which: X is an atom of oxygen, sulfur or a methylene group B represents a purine or pyrimidine base; L.sub.1 and L.sub.2, identical or different, represent hydrogen, an —O—C(O)— oxycarbonyl group, an —O—C(S)—NH— thiocarbamate group, an —O—C(O)—O— carbonate group, an —O—C(O)—NH— carbamate group, an oxygen atom, a phosphate group, a phosphonate group or a heteroaryl group comprising from 1 to 4 nitrogen atoms, substituted or unsubstituted by a saturated or unsaturated, linear or branched C.sub.8-C.sub.30 hydrocarbon chain; R.sub.1 and R.sub.2, identical or different, represent: a linear or branched C.sub.8-C.sub.30 hydrocarbon chain, saturated or comprising one or more unsaturations, a C.sub.8-C.sub.30 acyl chain, a diacyl chain in which each acyl chain is C.sub.8-C.sub.30, a diacylglycerol group in which each acyl chain is C.sub.8-C.sub.30, R.sub.3 represents a NH.sub.2—R.sub.4, NHR.sub.4R.sub.5 or NR.sub.4R.sub.5R.sub.6 group, in which R.sub.4, R.sub.5 and R.sub.6, identical or different, represent a hydrogen atom or a linear or branched C.sub.1-C.sub.6 alkyl chain or linear or branched C.sub.1-C.sub.6 hydroxyalkyl chain, or a heteroaryl group containing 1 to 4 nitrogen atoms, unsubstituted or substituted by a C.sub.2-C.sub.30 alkyl, or by a (CH.sub.2).sub.m—O—(CH.sub.2).sub.p—R.sub.9 group in which m=1 to 6 and p=0 to 20 and R.sub.9 represents hydrogen.

11. Method according to claim 1, in which a nucleolipid compound of formula (I) is used in which: X is an oxygen atom; B is chosen from adenine, guanine, cytosine, thymine and uracil; L.sub.1 and L.sub.2, identical or different, represent an —O—C(O)— oxycarbonyl group, an —O—C(O)—O— carbonate group, an —O—C(O)—NH— carbamate group, an oxygen atom or a phosphate group and/or one from de L.sub.1 and L.sub.2 represents hydrogen; R.sub.1 and R.sub.2, identical or different, represent a linear or branched C.sub.8-C.sub.30 hydrocarbon chain, saturated or comprising one or more unsaturations, a C.sub.8-C.sub.30 acyl chain, a diacyl chain in which each acyl chain is C.sub.8-C.sub.30, or a diacylglycerol group in which each acyl chain is C.sub.8-C.sub.30; R.sub.3 represents a hydroxy, amino, phosphate, phosphonate, thiophosphate, phosphonium, NH.sub.2—R.sub.4, NHR.sub.4R.sub.5 or NR.sub.4R.sub.5R.sub.6 group in which R.sub.4, R.sub.5 and R.sub.6, identical or different, represent a hydrogen atom or a linear or branched C.sub.1-C.sub.6 alkyl or linear or branched C.sub.1-C.sub.6 hydroxyalkyl chain.

12. Method according to claim 1, in which a nucleolipid compound of formula (I) is used in which: X is an oxygen atom; B is chosen from adenine, guanine, cytosine, thymine and uracil, preferably uracil or thymine; L.sub.1 is a phosphate group substituted by an R.sub.1 group, in which R.sub.1 is a diacylglycerol group in which each acyl group is C.sub.8-C.sub.30, L.sub.2 is hydrogen and R.sub.2 is not present, or L.sub.1 represents an —O—C(O)— oxycarbonyl group substituted by an R.sub.1 group and L.sub.2 represents and an —O—C(O)— oxycarbonyl group substituted by an R.sub.2 group, and R.sub.1 and R.sub.2, identical or different, each represent a linear or branched C.sub.8-C.sub.30 hydrocarbon chain, containing one or more unsaturations; R.sub.3 is a hydroxy group or an NR.sub.4R.sub.5R.sub.6 group in which R.sub.4, R.sub.5 and R.sub.6 represent a hydrogen atom.

13. Method according to claim 12, in which a nucleolipid compound of formula (I) is used in which: X is an oxygen atom; B is thymine; L.sub.1 is a phosphate group substituted by an R.sub.1 group, in which R.sub.1 is a diacylglycerol group in which each acyl group is C.sub.8-C.sub.30, preferably C.sub.8-C.sub.26, or more preferably C.sub.16-C.sub.20, L.sub.2 is hydrogen and R.sub.2 is not present, and R.sub.3 is a hydroxy group.

14. Method according to claim 12, in which a nucleolipid compound of formula (I) is used in which: X is an oxygen atom; B represents uracil; L.sub.1 represents an —O—C(O)— oxycarbonyl group substituted by an R.sub.1 group, L.sub.2 represents an —O—C(O)— oxycarbonyl group substituted by an R.sub.2 group, R.sub.1 and R.sub.2, identical or different, each represent a linear or branched C.sub.8-C.sub.30 hydrocarbon chain, preferably C.sub.16-C.sub.20, containing one or more unsaturations, R.sub.3 is an NR.sub.4R.sub.5R.sub.6 group in which R.sub.4, R.sub.5 and R.sub.6 represent a hydrogen atom.

15. Method according to claim 1, in which a nucleolipid compound of formula (I) is used, selected from: Thymidine 3′-(1,2-dipalmitoyl-sn-glycero-3-phosphate; (N-5′-(2′,3′-dioleoyl)uridine-N′,N′,N′-trimethylammonium tosylate).

16. Method according to claim 1, in which the separation step is carried out by decantation, centrifugation, filtration or mechanical wiping.

17. Method according to claim 1, in which the micropollutant is a medicament, a derivative of a medicament, a metabolite of a medicament, or a compound or a substance that is carcinogenic, mutagenic and/or reprotoxic (CMR) or a derivative or a metabolite thereof.

18. Method according to claim 1, in which the micropollutant is selected from ofloxacin, la ciprofloxacin, erythromycin, diclofenac, propranolol, metoprolol, carbamazepine, fluoxetine, dichlorvos, caffeine, ethinylestradiol, diuron, isoproturon, alachlor, aclonifen, chlorfenvinphos, quinoxifen, cyclophosphamide, doxorubicin, a taxane such as paclitaxel or docetaxel, a platinum derivative or 5-fluoracil.

19. Method according to claim 1, in which said surface is a surface based on glass, polymer, silicone or metal.

20. Use of at least one compound of formula (I) as defined in claim 1 for the decontamination of an aqueous liquid medium containing at least one micropollutant in molecular form or a surface contaminated with at least one micropollutant.

Description

[0158] The invention is illustrated by the following Examples.

Example 1: Decontamination of an Aqueous Liquid Medium Containing Propranolol® or Didofenac® by a Nucleolipid Compound of Formula (I)

[0159] Propranolol® and Didofenac® were used (Sigma-Aldrich).

[0160] The nucleolipids of formula (I) diC16dT and DOTAU were prepared according to the procedures described respectively in Khiati et al., Bioconjug. Chem, 2009, 20, 1765-1772, Bioconjug. Chem, 2009, 20, 1765-1772 and Chabaud et al., Bioconjug. Chem., 2006, 17, 466-472. By way of comparison, a commercially available decontaminant compound in powder form, Trivorex® (Prevor) was also used.

[0161] 1/ Preparation of a Calibration Solution of Propranolol®. Diclofenac® and Trivorex®

[0162] 7 mg of product (medicament or Trivorex®) are added to 7 ml deionized water (stock solution: 1 mg/mL).

[0163] The λmax was determined by spectrometer measurements for each compound. Different solutions were produced based on their stock solutions and assayed in 100 μl quartz cells with a UV Jacso V-630 spectrometer. The epsilon of each compound is determined at 258 nm, 266 nm, 276 nm and 289 nm (A=a×C+b with A the absorbance, C the concentration, a is the epsilon and b is the value of the y-axis at the origin).

[0164] The Trivorex® does not absorb in distilled water solution. The same protocol was used in tap water (the epsilon does not change in tap water).

[0165] The concentrations of the working solutions were thus determined for Propranolol® at 50 μg/mL and for Didofenac® at 20 μg/mL, for respective absorption wavelengths of 289 nm and 276 nm.

[0166] 2/ Study of the Decontamination of Propranolol® by diC16-3′-dT and Diclofenac® by DOTAU

[0167] The experiments were conducted in triplicate. 10 mg of DiC16dT was added to 50 mL of solution to be decontaminated (solution of Propranolol® at 50 μg/mL in distilled water or in tap water).

[0168] After incubation (15 min in deionized water or 2 hours in tap water) under magnetic stirring at ambient temperature, 600 μL of this solution was filtered over Millex-GS 0.22 μm membrane, MF-Millipore.

[0169] The spectra of the samples were acquired using a UV spectrophotometer with 100 μL quartz cells. The final concentrations of Propranolol® and the decontamination percentages were calculated by the multicomponent mode method (Wagdarikar et al., Pharm. Sci. Res., 2015, 545, 2013-2018).

[0170] The same protocol was used for a solution of Didofenac® at 20 μg/mL in distilled water or in tap water and using DOTAU, with an incubation time under magnetic stirring of 10 min in distilled water or 30 min in tap water.

[0171] The same protocol was followed, replacing the nucleolipid component with Trivorex® for each of the medicaments.

[0172] By way of comparison, solutions containing only Propranolol® or Didofenac® (respectively at 50 μg/mL and 20 μg/mL) in distilled water or in tap water were also subjected to a simple filtration over Millex-GS 0.22 μm MF-Millipore membrane, in the absence of nucleolipid compound.

[0173] For determining the real concentrations of Propranolol® and of Didofenac® and the percentage decontamination, formulae 1 and 2 below were applied.

[00001]$\begin{array}{cc}\mathrm{Formula}1\text{:}\mathrm{Determining}\mathrm{the}\mathrm{real}\mathrm{conectration}\mathrm{of}\mathrm{Propranolol}\circledR \mathrm{and}\mathrm{the}\mathrm{percentage}\mathrm{decontamination}\mathrm{by}\mathrm{the}\mathrm{multicomponent}\mathrm{method}.& \\ \left[\mathrm{Propranolol}\right]\mathrm{experimental}=\frac{\begin{array}{c}A\mathrm{mixture}266\mathrm{nm}\times \mathrm{.Math.}\mathrm{DiC}16dT289\mathrm{nm}-\\ \mathrm{.Math.}\mathrm{DiC}16dT266\mathrm{nm}\times A\mathrm{mixture}289\mathrm{nm}\end{array}}{\begin{array}{c}\mathrm{.Math.}\mathrm{Propranolol}266\mathrm{nm}\times \mathrm{.Math.}\mathrm{DiC}16\mathrm{dT}289\mathrm{nm}-\\ \mathrm{.Math.}\mathrm{DiC}16\mathrm{dT}266\mathrm{nm}\times \mathrm{.Math.}\mathrm{Propranolol}289\mathrm{nm}\end{array}}\%\mathrm{decontamination}=100-\left(\frac{\left[\mathrm{Propranolol}\right]\mathrm{experimental}}{\left[\mathrm{Propranolol}\right]\mathrm{working}\mathrm{solution}}\times 100\right)& \\ \mathrm{Formula}2\text{:}\mathrm{Determining}\mathrm{the}\mathrm{real}\mathrm{conectration}\mathrm{of}\mathrm{Diclofenac}\circledR \mathrm{and}\text{.Math.}\mathrm{the}\mathrm{percentage}\mathrm{decontamination}\mathrm{by}\mathrm{the}\mathrm{multicomponent}\mathrm{method}.& \\ \left[\mathrm{Diclofenace}\right]\mathrm{experimental}=\frac{\begin{array}{c}A\mathrm{mixture}266\mathrm{nm}\times \mathrm{.Math.}\mathrm{DOTAU}276\mathrm{nm}-\\ \mathrm{.Math.}\mathrm{DOTAU}258\mathrm{nm}\times A\mathrm{mixture}276\mathrm{nm}\end{array}}{\begin{array}{c}\mathrm{.Math.}\mathrm{Diclofenac}258\mathrm{nm}\times \mathrm{.Math.}\mathrm{DOTAU}276\mathrm{nm}-\\ \mathrm{.Math.}\mathrm{DOTAU}258\mathrm{nm}\times \mathrm{.Math.}\mathrm{Diclofenac}276\mathrm{nm}\end{array}}\%\mathrm{decontamination}=100-\left(\frac{\left[\mathrm{Diclofenac}\right]\mathrm{experimental}}{\left[\mathrm{Diclofenac}\right]\mathrm{working}\mathrm{solution}}\times 100\right)& \end{array}$

[0174] 3/ Data Analysis

[0175] Data analysis was carried out by testing the normality (Shapiro-Wilk test) and the homoscadasticity (Bartlett's test), then the ANOVA parametric test was used for detecting the significant differences between the decontamination methods.

[0176] When the ANOVA test was significant (p<0.05), the post-hoc Tukey test was used and was noted as follows: not significant (ns) for p<0.05, weakly significant (*) for p<0.05), very significant (**) for p<0.005, highly significant (***) for p<0.0005.

[0177] 4/ Results

[0178] The results are summarized in FIGS. 1 and 2.

[0179] a) FIG. 1 shows the decontamination levels obtained for Propranolol® or Diclofenac® in distilled water, under the following conditions: [0180] filtration alone, in the absence of compound of formula (I) (column in white); [0181] addition of a compound of formula (I), namely DOTAU or diC16dT, followed by a filtration (column in black); [0182] addition of Trivorex®, in the absence of compound of formula (I), followed by a filtration (column in grey).

[0183] A high level of decontamination is observed for the solution containing Propranolol® in the presence of diC16dT (93.69±2.04%) and for the solution containing Diclofenac® in the presence of DOTAU (98.03±0.51%). These decontamination levels are significantly higher than those obtained with Trivorex®, respectively of 55 t 5% (for the Propranolol®) and less than 5% (for the Didofenac®).

[0184] It is observed that the filtration alone over cellulose membrane gives a low level of decontamination (19.80±1.22%) for the solution containing Propanolol®, which has an affinity for the cellulose membrane, and a level of decontamination of almost zero for the solution containing Didofenac® (1.86±0.17%).

[0185] b) FIG. 2 shows the decontamination levels obtained for Propranolol® or Didofenac® in tap water, under the same conditions.

[0186] Similar results are observed to those obtained in distilled water: the only effective decontamination is that obtained by using the nucleolipids of formula (I) DOTAU or diC16dT.

Example 2: Study of the Decontamination of Propranol® and Didofenac® in the Presence of Several Nucleolipids of Formula (I)

[0187] Measurements were carried out on solutions of Propranolol® and Didofenac® containing either a nucleolipid of formula (I) (DOTAU or diC16dT), or both nucleolipids, added successively or simultaneously. By way of comparison, a measurement was also carried out with filtration alone, in the absence of compound of formula (I).

[0188] The different mixtures below were produced in triplicate.

[0189] For each medicament a mixture was prepared by adding 10 mg of nucleolipid DOTAU or diC16dT to 50 mL of solution of medicament, then 10 mg of nucleolipid DOTAU or diC16dT different from the first addition, or by dissolving 10 mg of each nucleolipid at the same time in 50 mL of solution of medicament. In both cases, a filtration was then carried out.

[0190] The measurements were taken after different incubation times at ambient temperature. The results are summarized in FIG. 3.

[0191] For Propranolol® (at 50 μg/mL), the following conditions were used: [0192] addition of diC16dT and Incubation 15 min (column In light grey); [0193] addition of diC16dT and incubation 15 min, then addition of DOTAU and incubation 60 min (column in dark grey); [0194] simultaneous addition of diC16dT and DOTAU and incubation 15 min (column in black); [0195] simultaneous addition of diC16dT and DOTAU and incubation 120 min (hatched column).

[0196] For Didofenac® (at 20 μg/mL), the following conditions were used: [0197] addition of DOTAU and incubation 10 min (column in light grey); [0198] addition of DOTAU and incubation 10 min, then addition of diC16dT and incubation 60 min (column in dark grey); [0199] simultaneous addition of diC16dT and DOTAU and incubation 10 min (column in black); [0200] simultaneous addition of diC16dT and DOTAU and incubation 120 min (hatched column).

[0201] At these different times, the decontamination is measured using a UV spectrophotometer (100 μL quartz cells) after having filtered 600 μL of working solution over Millex®-GS 0.22 μm membrane, MF-Millipore.

[0202] By way of comparison, a measurement was also carried out for each of the medicaments after filtration alone, in the absence of nucleolipid compound of formula (I) (DOTAU or diC16dT) (column in white).

[0203] 5/ Results

[0204] The results, summarized in FIG. 3, show that: [0205] in all cases, the addition of nucleolipid(s) of formula (I) (DOTAU and/or diC16dT), alone or in combination, allow effective and significant decontamination to be obtained, in comparison with filtration, which does not allow a satisfactory decontamination level to be obtained; [0206] for Diclofenac®, no significant difference was observed between the decontamination performed by DOTAU alone (97.06±1.35% after 10 min) or that performed by sequential or simultaneous addition of DOTAU and diC16dT. Nor does the incubation time result in any significant difference; [0207] for Propranolol®, the decontamination performed by diC16dT alone shows a level of 93.69±2.04% and it is observed that the simultaneous addition of DOTAU and diC16dT makes it possible to obtain a decontamination level of 72.71±2.44% after only 15 min.

[0208] These results make it possible to envisage the use of two different nucleolipids for decontaminating an aqueous liquid medium containing different types of micropollutants.

Example 3: Study of the Decontamination of Aqueous Mediums Comprising a Mixture of Micropollutants with diC16dT

[0209] The aim of this study is to test a system for decontaminating water according to the invention on pure water artificially contaminated with 13 micropollutants (“cocktail”).

[0210] These 13 micropollutants are the following medicaments and pesticides: erythromycin, propranolol, metoprolol, carbamazepine, fluoxetine, dichlorvos, ethinylestradiol, diuron, isoproturon, alachlor, aconifen, chlorfenvinphos, and quinoxifen.

[0211] The 13 micropollutants were diluted at concentrations at least 10 times greater than the limits of detection thereof in 500 mL of water.

[0212] 3 replicates of 50 mL of this solution were decontaminated with diC16dT and according to the same method of operation as that in Example 1, and the 4 samples (3 decontaminated samples+50 mL of non-decontaminated solution) were analyzed by LC-MS.

[0213] Materials and Methods

[0214] Chemical Products and Solvents

[0215] The analytical standards were purchased in analytical quality with a purity of ≥98% from Sigma-Aldrich (St Quentin Fallavier, France).

[0216] All the solvents used are of quality Optima™ LC-MS (Fisher Scientific, Illkirch, France), including the water used to create the 500 mL solution.

[0217] Preparation of the Stock and Working Solutions

[0218] The stock solutions (1 mg/mL) were prepared by diluting approximately exactly 1 mg of each standard in the corresponding volume of the appropriate solvents. The standards were weighed on Quintix 35-1S analysis scales (Sartorius, Aubagne, France).

[0219] In order to limit the degradation of the standards, all the solutions were kept at −20° C. immediately after preparation and until use.

[0220] LC-MS Analysis

[0221] Liquid Chromatography

[0222] The separation by chromatography was carried out with an HTC PAL automated sampling system (CTC Analytics AG, Zwingen, Switzerland) coupled with a HPLC Dionex Ultimate 3000 system (ThermoFisher Scientific, Les Ullis, France) equipped with two pumps (charging and elution) and a VIM (Valve Interface Module) making it possible to elute the SPE online in backflush mode.

[0223] Mass Spectrometry

[0224] The analyses were carried out in positive mode with a Q-Exactive (ThermoFisher Scientific, Les Ullis, France) equipped with a HESI (Heated Electrospray Ionisation) source (ThermoFisher Scientific, Les Ullis, France).

[0225] Acquisition and Exploitation of the Results

[0226] The acquisition and exploitation of the results was carried out with the Xcalibur software (ThermoFisher Scientific, Les Ullis, France). The signal corresponding to each of the contaminants was validated according to its m/z (with a tolerance set at 5 ppm) and retention time, and reintegrated manually if necessary.

[0227] Calibration curves were obtained for each molecule in LC-MS quality water with concentrations reaching twice the initial concentration of the test solution. The parameters of these calibration curves (slope, y-axis at the origin and linear regression coefficient) were obtained using Excel software, which was then used to quantify each molecule in the samples.

[0228] The results obtained are presented in Table 1 below.

[0229] For each molecule, the concentrations before and after decontamination (in μg/L) in each sample, the percentage decontamination and the standard deviation are shown.

TABLE-US-00001 TABLE 1 Before After Standard decontamination decontamination Decontamination deviation Micropollutant (μg/L) (μg/L) (%) (%) Carbamazepine 0.128 0.072 43.49 6.07 Erythromycin 3.998  0 (<LoD)* 100 0 Ethinylestradiol 1.912 0.023 98.80 0.55 Fluoxetine 0.103 0 (<LoD) 100 0 Metoprolol 0.104  0.0017 98.40 0.56 Propranolol 0.085 0 (<LoD) 100 0 Aclonifen 3.762 0 (<LoD) 100 0 Alachlor 0.092  0.0023 97.46 0.63 Chlorfenvinphos 0.075 0 (<LoD) 100 0 Dichlorvos 0.094 0.056 40.07 1.63 Diuron 0.098 0.023 76.87 3.12 Isoproturon 0.993 0.46  54.08 4.60 Quinoxifen 2.688 0 (<LoD) 100 0 Cocktail 14.132 0.63  95.51 0.48 *LoD = limit of detection

[0230] FIG. 4 represents the decontamination level obtained for each of the 13 micropollutants (FIG. 4A), as well as the overall decontamination level of the cocktail (solution containing the 13 micropollutants) (FIG. 4B3).

[0231] The results show that the method according to the invention makes it possible to obtain a significant decontamination for very low concentrations of micropollutants, of the order of or less than 1 μg/L.

[0232] For a cocktail of micropollutants, the results show that the decontamination is effective for a total concentration of several tens of μg/L.

Example 4: Decontamination of Contaminated Surface (Glass Slide)

[0233] 10 μL of Quantum Dots (CdSeS/ZnS, 1 g.L.sup.−1 in toluene, 6 nm) was deposited on a glass slide (Marienfeld 76×26×1 mm, pure white glass, cut edges, plain). It was allowed to evaporate under a hood for 1 hour. Then 20 μL of decontaminating solution was deposited.

[0234] The tests were carried out with a solution of DOTAU in water at 1% m/V or in an ionic liquid, 1-butyl-3-methylimidazolium bis(trifluoromethylsulfonyl)-imide (BMIM TFSI) at 1% m/V (i.e. 10 mg/mL).

[0235] After having left the decontaminating solution in contact with the contaminated glass slide for 15 min, the slide was cleaned by passing a wiper (Kimtech 05511) once vertically, then once horizontally. The slide is observed under UV (366 nm) and photographed.

[0236] By way of comparison, observation was also carried out of a contaminated slide before treatment, a contaminated slide with simple wiping with a wiper without contact with the decontaminating solution, and contaminated slides subjected to contact with water or ionic liquid, followed by wiping.

[0237] The contaminated slides are photographed before and after treatment, then the photos are processed with Mesurim® and Image J® image processing software.

[0238] The results obtained are presented in Table 2 below, expressed as percentage decontamination.

TABLE-US-00002 TABLE 2 Treatment after decontamination % decontamination Wiper 22% Water only 28% Solution of DOTAU in water 40% BMIM TFSI only 42% Solution of DOTAU in BMIM TFSI 74%

[0239] The results show that the presence of DOTAU in the decontaminating solution significantly increases the decontamination of the glass slide.