COLORIMETRIC AND FLUOROGENIC SYSTEM FOR THE DETECTION OF A CHEMICAL SUBSTANCE AND METHOD FOR DETECTING A CHEMICAL SUBSTANCE AND IMPLEMENTING IT

Abstract

The invention relates to a chemical substance detection system comprising at least one fluorescent compound with color-changing capability carried by particles of at least two different types, arranged on a solid support. A method for detecting a chemical substance in a medium comprises bringing this medium into contact with the particles carrying the compound of this detection system, acquiring the colorimetric and fluorogenic responses induced by this contact, and deducing, based on all of these responses, the absence or specific presence of said substance in the medium.

Description

Title of the invention: COLORIMETRIC AND FLUO-ROGENIC SYSTEM FOR THE DETECTION OF A CHEMICAL SUBSTANCE AND METHOD FOR DETECTING A CHEMICAL SUBSTANCE USING IT

[0001] The present invention falls within the field of the detection and identification of chemical substances likely to be contained in an environment.

[0002] More particularly, the present invention relates to a system for detecting one or more chemical substances, as well as a method for preparing such a system, and a kit for detecting one or more chemical substances comprising it. The invention also relates to a method for detecting a chemical substance likely to be contained in a medium, implementing such a system.

[0003] The invention finds particular and advantageous application for the detection, and where appropriate the identification, of toxic chemical substances, in particular organophosphorus substances banned by the Organisation for the Prohibition of Chemical Weapons (OPCW), such as sarin, tabun, soman, VX, Novichoks, or organophosphorus pesticides, such as malathion, fenthion, diphenyl chlorophosphate (DPCP), parathion or paraoxon-methyl, of toxic warfare compounds, in particular vesicant agents and emetic agents, such as arsenic compounds, and of industrial toxic compounds (known under the name TIC).

[0004] In particular, organophosphorus substances have proven toxicity to the human body. Indeed, these substances may be involved in the mechanism of inhibition of serine proteases and, in particular, of acetylcholinesterase, which intervenes in synaptic junctions and whose deregulation of activity can prevent muscle relaxation and thus cause death by asphyxiation.

[0005] These substances can be included in the formulation of insecticides, pesticides or even chemical combat agents (such as G series organophosphorus compounds, such as sarin (known as GB) or V series organophosphorus compounds, such as VX), and, due to the high lethality of these substances, it is important to have systems available for their detection and preliminary identification.

[0006] Some detection systems used to date for this purpose are based on technologies involving physical measurement means, such as ion mobility spectroscopy, flame photometry, infrared and Raman spectroscopies, with the difficulty that these systems require expensive complex equipment. and not necessarily suitable for all intervention environments in terms of mass and size, to which the operator's expertise must be added.

[0007] It has otherwise been proposed by the prior art to detect the presence of an organophosphorus substance, in liquid phase, by two combined techniques, in particular by colorimetric and electrochemical means (De et al., 2010, Tetrahedron Letters, 51, 1754-1757), or by fluorogenic and electrochemical means (Guo et al., 2011, Talanta, 87, 276-283). These detection methods are however impractical to carry out, and they can only be implemented in the laboratory, not allowing detection in the field. They also have low detection accuracy of the target substances, and do not allow discrimination of a particular chemical substance from other substances of close structure.

[0008] In view of what exists, the present inventors have turned towards the design of a detection system usable for the detection of one or more chemical substances, which system must allow the detection of said chemical substance(s) and, when there are several, ideally, the discrimination of said chemical substances, and meeting criteria of sensitivity, reliability, speed, portability, practicality of use, and which can allow detection and, where appropriate, simple discrimination and, for example, visual discrimination with the naked eye, or by means of portable equipment, with high precision.

[0009] To this end, the present inventors turned to the development of a solid-phase detection system, combining practicality of use, transport and storage. They discovered that compounds corresponding to a particular general formula have optical properties, more particularly colorimetric properties and fluorescence properties, which are modified by their contact with target chemical substances, in particular organophosphorus substances. Furthermore, when these compounds are carried by solid particles, their optical properties are also affected depending on the particular type of particles used, and, particularly surprisingly, their colorimetric and / or fluorogenic responses caused by their contact with a chemical substance are also affected differently depending on the type of particles which carry them.Each target chemical substance in fact causes a colorimetric response (absence or presence of colorimetric change, and characteristics of this change) and a fluorogenic response (absence or presence of variation in the fluorescence peak, and characteristics of variation in terms of intensity and / or wavelength) which are specific for each pair of detection compound and given type of particle, and which, for the same compound, can vary depending on the type of particle associated with it.

[0010] Thus, it has been discovered by the present inventors that the implementation of a compound of particular general formula, carried respectively by a plurality of different types of particles, and the combination of a colorimetric reading and a fluorescence reading, makes it possible to detect in solid phase, and with great precision, and even discriminate, by correctly choosing the "particle / compound" pairs used for detection, a specific target chemical substance contained in a medium. This detection, and where appropriate identification, can advantageously be carried out easily and quickly, visually with the naked eye, under daylight for the colorimetric reading, and, for the fluorescence reading, by using only an ultraviolet (UV) lamp emitting at an appropriate wavelength, and / or by means of standard portable field equipment, such as a spectrometer, giving access to quantifiable information and UV lighting sources.

[0011] Thus, according to a first aspect, there is proposed according to the present invention a system for detecting one or more chemical substances, in particular in liquid form, likely to be contained in a medium, this system comprising at least one compound of general formula (I):

[0012] [Chem.l] (I)

[0013] in which Ari represents a nitrogen-containing aromatic heterocycle, optionally substituted by one or more linear or branched alkyl radicals, preferably C1-C6, or Ari represents a fused polycyclic aromatic group containing at least one nitrogen-containing aromatic heterocycle, each of the rings of said fused polycyclic aromatic group being carbocyclic or nitrogen-containing, and being optionally substituted by one or more linear or branched alkyl radicals, preferably C1-C6, Ri, R2 and R3, identical or different, each represent a hydrogen atom or a group R4 of general formula (II):

[0014] [Chem.2]

[0015] in which Ar2 represents a phenyl group substituted by a group R5 chosen from a hydrogen atom, a halogen atom, in particular bromine, an amino group primary -NH2, a hydroxyl group -OH, a sulfhydryl group -SH and a group -R6, -NHR6, -N(R6)2, -OR6 or -SR6, where R6 represents a linear or branched alkyl radical, preferably C1-C20, in particular methyl, Ar2 being further optionally substituted by one or more linear or branched alkyl radicals, preferably C1-C6, Rb R2 and R3 not all simultaneously representing a hydrogen atom, and in which each compound of general formula (I) is carried by, in particular impregnated on, particles of at least two different types, the particles of the same type and carrying the same compound of general formula (I) being arranged on a solid support distinct from the other particles of the system.

[0016] In the present description, the term “nitrogenous aromatic heterocycle” is understood to mean, in a conventional manner in itself, an aromatic cycle comprising at least one nitrogen atom in the cycle, for example one or two nitrogen atoms in the cycle. This nitrogenous aromatic heterocycle preferably comprises 6 atoms in the cycle, these atoms furthermore preferably being only carbon or nitrogen atoms.

[0017] Furthermore, the term “condensed polycyclic aromatic group” means a group comprising a plurality of aromatic rings, each of these rings being condensed with at least one other of these rings. Preferably, each of the aromatic rings of such a group comprises 6 atoms in the ring, these atoms furthermore preferably being only carbon or nitrogen atoms.

[0018] By particles of different types is meant particles having different surface chemistries from each other. These particles may be of different chemical nature, for example silica particles and alumina particles, or be particles of the same chemical nature, but functionalized on the surface and / or activated differently from each other, such as: simple silica and silica functionalized by amine groups; or neutral alumina, basified alumina and acidified alumina.

[0019] The detection system according to the invention may advantageously comprise a plurality of different compounds of general formula (I), each of said compounds being carried by, in particular, particles of at least one, preferably at least two, or even more, different types.

[0020] By "particles of the same type and carrying the same compound of general formula (I) being arranged on a solid support distinctly from the others", it is meant herein that the particles of the same type and carrying the same compound of general formula (I) are arranged on a support so as to be separated in space from the other particles of the system, and not to interfere with them, so that the results, in terms of optical response to contact with a target chemical substance, obtained for each pair "particles of the same type and carrying a same compound of general formula (I)” are not altered by those obtained by the other pairs “particles of the same type and carrying the same compound of general formula (I)”.

[0021] Thus, in particular embodiments of the invention, particles of the same type and carrying the same compound of general formula (I) are arranged on a separate, individual support, which is specific to them. The different supports can then be assembled on a common base, thus forming a single detection substrate, which is easier to use.

[0022] In alternative embodiments of the invention, all of the particles are arranged on the same support, the particles of the same type and carrying the same compound of general formula (I) being arranged on a separate zone of said support, which is specific to them, without overlapping with the separate zone(s) of the other pairs “particles of the same type and carrying the same compound of general formula (I)”.

[0023] In such embodiments, said distinct zones are in shapes that may be substantially circular, rectangular or square.

[0024] By "without overlapping", it is understood, conventionally, that the distinct zone(s) of each of the pairs "particles of the same type and carrying the same compound of general formula (I)" do not mix with the distinct zone(s) of the other pairs "particles of the same type and carrying the same compound of general formula (I)"•

[0025] Of course, any hybrid embodiment between these two alternative embodiments also falls within the scope of the invention, certain “particle / compound” pairs of the detection system being able to be arranged on the same support, in distinct zones of the latter, and others on distinct supports.

[0026] Each of the compounds according to the invention, corresponding to the general formula (I), is advantageously capable of being transformed upon contact with at least one chemical substance that it is desired to detect, this transformation being the sign of the presence of this chemical substance, and materializing by a change in color, detectable by colorimetric detection, and / or a change in the fluorescence signal, detectable by fluorogenic detection, and this transformation being different depending on the type of particles by which the compound is carried.

[0027] More specifically, for each type of particle by which it is carried, the compound according to the invention has a given initial colored state and fluorescence signal. In the presence of a given target chemical substance, it may have another colored state and / or a fluorescence signal of different intensity and / or at a different wavelength, these changes in optical properties being variable depending on both the particular chemical substance present, and the type of particles carrying the compound.

[0028] As indicated above, the system according to the invention thus makes it possible, by the quantity, and where appropriate the redundancy, of information that it provides, to reliably and precisely detect, and where appropriate to discriminate, one or more chemical substances, in particular in liquid form, the degree of detection reliability obtained being all the greater as the number of “particles of the same type / same compound of general formula (I)” pairs used is large. Indeed, it has been observed by the present inventors that each chemical substance to be detected is associated with a set of data expressed in terms of the combination of a colorimetric response / absence of response and a fluorogenic response / absence of response associated with each “particles of the same type / same compound of general formula (I)” pair that can be envisaged, this set of data being different from one chemical substance to another.Thus, by an adequate choice of the number and nature of such pairs implemented, it is possible to associate with each chemical substance to be detected a signature, in the form of a set of optical data, which is specific to it, and which allows, not only to detect it with a high level of reliability, but also to distinguish it specifically from other chemical substances.

[0029] The detection system of the invention can in particular allow, by the choice of appropriate “particles of the same type / same compound of general formula (I)” pairs, the discrimination of distinct chemical compounds belonging to the same family, such as, by way of non-limiting example, organophosphorus compounds (such as those of the G series, of the V series or organophosphorus nerve agents recently added to Table 1 of the annex to the OPCW Convention for the Prohibition of Chemical Weapons S / 1821 / 2019 / Rev.l / Add.l (May 20, 2020)), vesicants (such as sulfur mustard gas, nitrogen mustard gas, lewisite), chemical industrial toxicants (such as ammonia, chloropicrin), pesticides.In such contexts, the combination of the two detection modes, colorimetric and fluorogenic, applied to a plurality of distinct “particles of the same type / same compound of general formula (I)” pairs, advantageously makes it possible to collect all the information essential to the identification of the threat, as well as to prevent possible interference between different toxic substances present.

[0030] The detection system according to the invention is particularly suitable for the solid phase detection of chemical substances present in a medium in liquid form.

[0031] The detection system according to the invention can furthermore meet one or more of the characteristics described below, implemented in isolation or in each of their technically operational combinations.

[0032] The general formula (II) above, representing the R4 group, encompasses both the trans isomeric forms and the cis isomeric forms of the vinyl double bond.

[0033] Preferably, the compound of general formula (I) has a trans conformation at each of the vinyl bonds formed between Ari and each of the Ar2 groups.

[0034] When Ari represents a nitrogen-containing aromatic heterocycle, each of the R4 groups of the molecule is preferably connected to Ari in the ortho or para position relative to a nitrogen atom of this nitrogen-containing aromatic heterocycle. When Ari represents a fused polycyclic aromatic group, at least one of the R4 groups of the molecule is preferably connected to Ari in the ortho or para position relative to a nitrogen atom of the nitrogen-containing aromatic heterocycle of this fused polycyclic aromatic group.

[0035] In general formula (I), Ari is preferably chosen from the groups of general formulas (Ilia), (Illb), (IIIc) and (Illd):

[0036] [Chem.3]

[0037] [Chem.4]

[0038] [Chem.5]

[0039] [Chem.6]

[0040] each of these groups of general formulas (IIIa), (IIIb), (IIIc) and (IIId) being optionally substituted by one or more linear or branched alkyl radicals, of preferably in C1-C6, and preferentially in C1-C3.

[0041] Preferably, in the general formula (II), Ar2 represents a phenyl group substituted by said R5 group in the para position relative to the vinyl bond to Arb. The substitution by the R5 group can otherwise be carried out in the ortho position, or in the meta position, relative to the vinyl bond to Arb.

[0042] For each of the Rh groups R2 and R3 not representing a hydrogen atom, R6 preferably represents a linear or branched alkyl radical, C1-C20, preferably C1-C6, and preferentially C1-C3. R6 preferably represents a methyl radical.

[0043] Preferred compounds of general formula (I) according to the invention are such that: - R2 and R3 represent a hydrogen atom, - or Ri and R2 are identical and R3 represents a hydrogen atom, - or Rb R2 and R3 are identical.

[0044] Such embodiments advantageously facilitate the synthesis of the compound of general formula (I) forming part of the detection system according to the invention.

[0045] Particularly preferred within the scope of the invention are the compounds of respective general formulas (IV), (V) and (VI):

[0046] [Chem.7] R s [I ' —P (IV)

[0047] in which Y represents a nitrogen atom or, preferably, a CH group,

[0048] [Chem. 8]

[0049] or

[0050] [Chem.9] R

[0051]

[0052]

[0053] the substituents R2 and R3 being as defined above. More particularly, compounds of general formula (I) may correspond to the respective general formulas (IVa), (IVb), (Va), (Vb), (Vc), (Via), (VIb), (Vie), in which R5 is as defined above: [Chem. 10]

[0054]

[0055] in which Y represents a nitrogen atom or a CH group, and R5 is preferably connected to the phenyl group in the para position relative to the vinyl bond, [Chem. 11]

[0056] in which Y represents a nitrogen atom or, preferably, a CH group, and each of the R5 groups is preferably connected to the phenyl group in the para position relative to the vinyl bond,

[0057] [Chem. 12] (Go)

[0058] in which R5 is preferably connected to the phenyl group in the para position relative to the vinyl bond,

[0059] [Chem. 13]

[0060] in which each of the R5 groups is preferably connected to the phenyl group in the para position relative to the vinyl bond,

[0061] [Chem. 14] (Vc)

[0062] in which each of the R5 groups is preferably connected to the phenyl group in the para position relative to the vinyl bond,

[0063] [Chem. 15] 'N' ■„N

[0064]

[0065] (Via.) in which R5 is preferably connected to the phenyl group in the para position relative to the vinyl bond, [Chem. 16] '.N (VI b)

[0066]

[0067] wherein each of the R5 groups is preferably branched to the phenyl group in the para position relative to the vinyl bond, [Chem. 17] ,Rl

[0068] in which each of the R5 groups is preferably branched to the phenyl group in the para position relative to the vinyl bond.

[0069] In the set of general formulas (IVa), (IVb), (Va), (Vb), (Via), (VIb), (Vie) above, the group of general formula (lia) or each of the groups of general formula (lia):

[0070] [Chem. 18]

[0071] is preferably connected in the ortho or para position of a nitrogen atom of the nitrogen-containing aromatic heterocycle.

[0072] Particular compounds of general formula (Vc) also correspond to the general formula (Vc'):

[0073] [Chem. 19]

[0074] In all of the general formulas above, each of the R5 groups further preferably represents a hydrogen atom, a halogen atom and a -R6, -NHR6, -N(R6)2, -OR6 or -SR6 group, where R6 represents a linear or branched C1-C6, preferably C1-C3, alkyl radical, and preferably a methyl radical.

[0075] The compounds of general formula (I) according to the invention can be purchased from a supplier or can be synthesized by conventional organic synthesis techniques involving, for example, coupling reactions, such as Heck coupling, Suzuki coupling, or reactions involving the use of microwaves.

[0076] The compounds of general formula (I) according to the invention can in particular be obtained by a Knoevenagel type condensation reaction, for example by adapting, to the particular compound targeted, the operating protocols described in the following publications: Brasselet et al., Chem. Mater. 1999, 11 (7), 1915-1920; Chérioux et al., Chem. Mater. 1998, 10, 1984-1989; Bonaccorso et al., Chem- PhysChem, 2018, 19 (15), 1917-1929.

[0077] The particles used in the detection system according to the invention may be inorganic particles, organic particles or organic-inorganic hybrid particles, for example, so-called “core-shell” particles with an inorganic core and an organic shell.

[0078] As examples of inorganic particles, mention may be made of: - silica particles SiO2; - silica particles grafted with organic groups, for example, silica particles grafted with primary amine groups -NH2 or aminopropyl groups; - alumina particles; - zinc oxide particles; - titanium oxide particles; - diatomaceous earth particles; - zeolite particles; - geopolymer particles.

[0079] As examples of organic particles, mention may be made of polymeric particles, such as: - polyethylene particles; - polyamide particles, such as nylon particles; - biopolymer particles, such as starch particles, cellulose particles, agar-agar particles.

[0080] Furthermore, the particles, in general, must advantageously have an average particle size compatible for use, before integration into the detection system, in a composition intended to be deposited on a support and, for example, may have an average particle size ranging from 0.1 to 500 μm and, more particularly, from 0.1 to 50 μm.

[0081] In particular embodiments of the invention, the particles of at least one, preferably several, of said different types of particles, and preferably the particles of all the types of particles used, are inorganic particles, preferably chosen from silica particles, silica particles grafted with organic groups, alumina particles, zinc oxide particles, titanium oxide particles, diatomaceous earth particles, zeolite particles and geopolymer particles.

[0082] By way of example, the following different types of particles may be used within the framework of the invention: - silica particles SiO2, for example having an average size of 2 to 25 pm and a pore size of 60 Å for a pore volume of 0.75 cm2 / g; - silica particles functionalized by primary amine groups SiO2 -NH2, for example having an average particle size of 40-75 pm with a pore size of 110 Å; - neutral alumina particles Al2O3-neutral, activated alumina, neutralized (in water) at pH 7.0 + / - 0.5, Brockmann I, in particular of standard grade, for example having a pore size of 58 Å and a particle size between 40 and 160 pm (205 m2 / g); - basic alumina particles Al2O3-basic, activated alumina, basified (in water) at pH 9.5 + / - 0.5, Brockmann I, in particular of standard grade, for example having a pore size of 58 Å and a particle size of 150 mesh (205 m2 / g); - acid alumina particles Al2O3-acid, activated alumina, acidified (in water) to pH 4.5 + / - 0.5, Brockmann I, in particular of standard grade, for example having a pore size of 58 Å and a particle size between 50 and 300 mesh (155 m2 / g).

[0083] The particles forming part of the detection system according to the invention carrying a compound of general formula (I), can be obtained by impregnation of particles with a so-called impregnation solution, comprising a compound of general formula (I) and an organic solvent, then drying of the impregnated particles obtained by evaporation of the solvent, in particular by vacuum distillation.

[0084] The organic solvent used is advantageously chosen so as to meet the following criteria: - it must be capable of solubilizing the compound of general formula (I); - it must be compatible with the particles intended to be impregnated by the compound, that is to say it must not solubilize or cause the aggregation of the particles during impregnation; - it must be easy to evaporate after the impregnation of the particles has been carried out and, in particular, it may advantageously have a boiling point below 250°C at atmospheric pressure, for example below 100°C; - it must preferably be a polar solvent to best solubilize the compound of general formula (I).

[0085] As examples of solvents which may be used for the impregnation of particles with a compound of general formula (I), mention may be made of protic polar solvents, such as: - alcoholic solvents, for example ethanol, isopropanol, 2-butoxyethanol, benzyl alcohol, ethylene glycol, 1-hexanol, 2-isopropoxyethanol; and - water.

[0086] Mention may also be made of aprotic polar solvents, such as: - ketonic solvents, such as cyclopentanone, γ-butyrolactone, 2-butanone, acetone; - ether solvents, such as tetrahydrofuran, 1,2-dimethoxyethane; - and nitrile solvents, such as acetonitrile.

[0087] The concentration of compound of general formula (I) in the impregnation solution may for example be equal to 0.25 g / L

[0088] The mass quantity of compound of general formula (I) may furthermore, for example, be greater than or equal to approximately 0.1% of the mass quantity of particles subjected to impregnation.

[0089] In particular embodiments of the invention, the particles are arranged on the support included in a layer comprising, in addition to these particles, at least one organic binder, which means, in other words, that said layer is a layer of composite material comprising a matrix of organic binder(s), in which the particles are trapped.

[0090] The organic binder or binders may be, in particular, polymeric binders, preferably apolar, such as: - polymeric binders comprising styrenic repeating units, such as polystyrene supplied by Supelco under product reference 81404; polystyrene having a mass molecular weight Mw of 35,000 supplied by Aldrich under product reference 331651; polystyrene having a mass molecular weight Mw of 350,000 and a number molecular weight of 170,000 supplied by Aldrich under product reference 441147; poly(styrene-co-methyl methacrylate) having a mass molecular weight ranging from 100,000 to 150,000 supplied by Aldrich under product reference 462896; a polystyrene-b-poly(ethylene-ran-butylene)-b-polystyrene block copolymer (ran meaning that the block concerned is a random polymer resulting from the polymerization of ethylene and butylene) having a mass molecular weight of 89000 supplied by Aldrich under product reference 200565; - polydimethylsiloxane type binders, - and paraffin-type binders.

[0091] Said layer advantageously immobilizes the particles carrying the compound of general formula (I) on the support, while protecting them from aqueous substances.

[0092] Each of the supports on which particles carrying a compound of general formula (I) are arranged is preferably of the porous type. It may be a support formed from paper (such as chromatography paper), a support made from non-woven fibers (for example, a mixture of cellulose fibers and polyester fibers), it being understood that the support must be capable of being impregnated by the particles carrying the compound, and that it must preferably be of the non-fluorescent type.

[0093] Each of the supports is preferably flat, and is presented for example in the form of a strip.

[0094] An additional object of the invention is a detection substrate comprising, assembled on the same base, preferably flat, a plurality of supports as defined above, on each of which is arranged a different pair of “particles of the same type / same compound of general formula (I)”.

[0095] Another aspect of the invention relates to a method for preparing a detection system according to the invention. This method comprises steps of: - preparation of a plurality of compositions, called deposition compositions, different each containing, respectively, a compound of general formula (I) carried by particles of a different type of particles, at least one organic solvent, and optionally at least one organic binder, - and depositing each of these compositions on a solid support, distinctly from each other, that is to say distinctly in space.

[0096] The step of preparing said plurality of deposition compositions comprises, as a preliminary step, a step of preparing the particles carrying a compound of general formula (I), preferably by impregnating said particles with an impregnation solution containing said compound, as described above in the present description. Depending on the compound used, it may comprise, as a further preliminary step, the synthesis of this compound, in particular according to one of the methods mentioned above.

[0097] The preparation of the deposition compositions, each comprising a different pair of “particles of the same type / same compound of general formula (I)”, can be carried out by dispersing the particles carrying the compound in the organic solvent(s), to which, if appropriate, one or more polymeric binders have been added.

[0098] The organic solvent(s) used in the composition of the deposition compositions are preferably apolar solvents, which do not allow the compound present in or on the surface of the particles to be solubilized and thus do not cause the compounds from the particles to be desorbed.

[0099] They preferably, advantageously, have a boiling point above 60°C in order to avoid excessively rapid evaporation during deposition and below 250°C in order to be able to dry after deposition of the particles on the support.

[0100] In particular, the organic solvent(s) may be hydrocarbon solvents and, more specifically: - saturated aliphatic solvents, such as hexane, cyclohexane, heptane, octane, nonane, decane, undecane, dodecane, isane and their isomers; - aromatic solvents, such as naphthalene, toluene, xylene; - terpenoid solvents, such as pinene, carene, limonene.

[0101] The organic binder(s) are preferably polymeric binders, in particular as described above with reference to the layer immobilizing the particles on the support.

[0102] In particular, the optional polymeric binder(s) may advantageously be apolar binders, such as polymeric binders comprising repeating styrenic units or of the polydimethylsiloxane type.

[0103] The deposition compositions obtained must contain sufficient compound of general formula (I), and therefore sufficient particles carrying this compound, to obtain optical signals of maximum intensity, in particular maximum coloring density. It is within the skill of the person skilled in the art to determine the particle concentration in the composition which is adequate for this purpose.

[0104] In this respect, the formulation of each deposition composition is preferably carried out in such a way that each of the final colored renderings obtained after a colorimetric change triggered by bringing the compound of general formula (I) into contact with target substances is significant, that is to say that the color difference (AECie 1994) between the initial colored resultant Rj and each of the final colored resultants Rfb Rf2, etc., is at least greater than 10% of the maximum color difference (AECie i994max = 140), i.e. AECiEi994max > 14. Preferably, a color difference between Ri and the Rfb Rf2, etc., greater than 20% of the maximum color difference (AECie 1994max - 140), i.e. AEciE1994max > 28, is targeted.

[0105] It is possible to adjust the initial colored resultant Ri and each of the final colored resultants Rfb Rf2, etc., by playing on several factors: - the choice of the pair(s) “particles of the same type / same compound of general formula (I)”, - the quantity of compound of general formula (I) per mass of particles; - the mass ratio of particles in the deposit composition, the combined determination of these factors being within the competence of a person skilled in the art.

[0106] The step of depositing the deposition compositions on a solid support can be carried out by any technique conventional in itself for those skilled in the art allowing the deposition of a liquid or pasty composition on a solid support, such as screen printing (for example, through a stencil-type metal mask with a wide opening) or deposition by doctor blade coating (also known as “doctor blade coating”).

[0107] The deposition compositions must have an adequate viscosity to allow their deposition on a solid support by such techniques, this viscosity being able to be easily adjusted by a person skilled in the art, by determining the adequate quantity of particles, and where appropriate the adequate quantity of organic binder, which are contained therein.

[0108] The step of depositing the deposition compositions on a solid support is preferably followed by drying, particularly in the open air, so as to ensure evaporation of the organic solvent(s).

[0109] Each support used in the preparation method according to the invention may meet one or more of the characteristics described above with reference to the detection system according to the invention. It is preferably flat, and for example formed from paper.

[0110] In particular embodiments of the invention, the deposition of the different deposition compositions on a solid support is carried out respectively on distinct zones of the same support, each of the compositions being deposited on a zone of the support not overlapping with the deposition zones of the other compositions.

[0111] In alternative embodiments of the invention, the deposition of the deposition compositions on a solid support is carried out respectively on separate individual supports. The method according to the invention then preferably comprises a final step of assembling the different separate supports, each supporting a specific “particles of the same type / same compound of general formula (I)” pair, on a common, preferably flat, base.

[0112] Here again, any hybrid formula between these two modes of implementation falls within the scope of the invention.

[0113] The detection system obtained at the end of the preparation process according to the invention thus groups together at least two (and where appropriate any number greater than two) different types of particles associated with the same compound of general formula (I). In the particular embodiments in which it comprises one or more additional compounds of general formula (I), each of these additional compounds may be carried by particles of the same type, or, respectively, by different types of particles, these types of particles possibly being identical, or different, compared to the types of particles carrying the 1st compound of general formula (I).

[0114] The detection system according to the invention can thus contain a plurality of pairs “particles of the same type / same compound of general formula (I)” all different from each other, each immobilized on a support separately from the others in space.

[0115] The initial optical properties, in particular colorimetric and fluorogenic, of each of these pairs can advantageously be determined by conventional methods in themselves. Their optical properties in the presence of predefined target chemical substances can also be predetermined. All of these data, expressed in terms of colorimetric variation or absence of colorimetric variation, and variation of the fluorescence signal or absence of fluorescence variation, can be stored in a database, making it possible to associate each of these predefined target chemical substances with a combination of data of colorimetric and fluorogenic responses specific to it, with respect to a given set of different “particles of the same type / same compound of general formula (I)” pairs, this combination of data constituting a signature specific to this predefined target chemical substance, allowing it to be reliably discriminated against in relation to other equally predefined target chemical substances.

[0116] In this regard, an additional aspect of the invention relates to a kit for detecting, and where appropriate discriminating, or pre-identifying, one or more chemical substances, in particular in liquid form, likely to be contained in a medium, this kit comprising: - a detection system according to the invention, - and a colorimetric and fluorogenic database making it possible to establish the correspondence between the colorimetric responses and the fluorogenic responses observed for each different “particles of the same type / same compound of general formula (I)” pair included in said detection system, and each of said chemical substances.

[0117] The detection system according to the invention, and the kit which contains it, are particularly suitable for the detection, and even the pre-identification, of one or more chemical substances present in liquid form in a medium.

[0118] Thus, another aspect of the invention relates to a method for detecting a chemical substance, in particular a liquid substance, likely to be contained in a medium, comprising steps of: - bringing said medium into contact with all of the particles carrying a compound of general formula (I) of a detection system according to the invention; - acquisition of the colorimetric response and the fluorogenic response induced by said contact, for each different “particles of the same type / same compound of general formula (I)” pair included in said detection system, - deduction, as a function of all of said colorimetric responses and said fluorogenic responses, of the absence or presence, where appropriate specific, of said substance in said medium.

[0119] The method according to the invention may comprise a prior step of adequate selection of the different pairs “particles of the same type / same compound of general formula (I)” entering into the constitution of the detection system, as a function of the particular chemical substance whose presence is suspected in the medium, and which is to be detected. This selection is preferably carried out so as to make it possible to discriminate, by the method according to the invention, this chemical substance from other chemical substances of the same type, the presence of which is also suspected. Thus, preferably, all of the pairs “particles of the same type / same compound of general formula (I)" entering into the constitution of the detection system are chosen so that the combination of their colorimetric and fluorogenic responses in the presence of the target chemical substance is specific to the latter. As indicated above, a higher number of different "particles of the same type / same compound of general formula (I)" pairs, chosen appropriately, makes it possible to increase the reliability of discrimination of the target chemical substance.

[0120] The step of bringing the medium into contact with the particles of the detection system is carried out so that each pair “particles of the same type / same compound of general formula (I)” is brought into contact with the medium. This contacting can be carried out by depositing, on the surface of each support or each zone of the support supporting particles carrying a compound of general formula (I), on the latter, one or more drops of the medium to be analyzed. It can otherwise, for example, be carried out by rubbing the support(s) against a surface suspected of being contaminated by the target chemical substance.

[0121] Between the step of bringing into contact and the step of acquiring the optical responses induced by bringing the particles carrying the compounds into contact with the medium being analyzed, a waiting time may be provided so that, where appropriate, the medium has time to penetrate to the compounds of general formula (I) carried by the particles immobilized in the layer of organic binder, the chromatic change and / or the shift of the fluorescence signal then generally occurring almost instantaneously.

[0122] The step of acquiring the colorimetric response and the fluorogenic response induced by bringing each different “particles of the same type / same compound of general formula (I)” pair into contact with the medium to be analyzed can advantageously be carried out simply and quickly, and what is more, using standard equipment that is not heavy or bulky and easy to transport.

[0123] The colorimetric responses can in particular be observed visually, with the naked eye. They can otherwise be determined by instrumented reading of the UV-visible spectra of each pair “particles of the same type / same compound of general formula (I)”.

[0124] The fluorogenic responses can also be observed visually, with the naked eye, under illumination by a UV lamp, at a suitable wavelength, for example at 312 nm or 365 nm. They can otherwise be evaluated by means of a spectrometer, in particular a portable one, under a suitable excitation wavelength, for example at 312 nm or 365 nm, such an acquisition means having the advantage of providing quantifiable results, thereby increasing the precision of detection and pre-identification of the chemical substance present.

[0125] The colorimetric and spectral data thus obtained characterize, for each pair “particles of the same type / same compound of general formula (I)” of the detection system, the color change or the absence of change (which also constitutes information), as well as the change in fluorescence emission or the absence of such change (which also constitutes information). The combination of these data constitutes the optical signature of the target chemical substance, associated with its particular chemical structure.

[0126] The deduction of the specific presence or absence of the target substance in the medium can then be carried out by comparing all the colorimetric and fluorogenic responses obtained with a pre-established database. This comparison can be carried out manually, or by appropriate computer means.

[0127] As indicated above, by an adequate choice of the number and type of different “particles of the same type / same compound of general formula (I)” pairs used, it is possible to detect the presence of a target chemical substance, and to pre-identify the chemical family of this substance, and even this substance itself.

[0128] The target chemical substance may be: - a toxic war compound, such as an NRBC-E (nuclear, radiological, biological, chemical and explosive) toxicant, a vesicant or an emetic agent such as an arsenic compound, - a toxic industrial chemical compound - and / or a pesticide.

[0129] It may in particular be an organophosphorus substance.

[0130] More specifically, chemical substances capable of being detected, and where appropriate pre-identified, by means of a detection system according to the invention, and of the method which implements it, may be: - organophosphorus plant protection products, such as malathion, fenthion, chlorpyrifos, omethoate, dimethoate, phosalone, dichlorvos, trichlorfon, phosmet, phosalone, parathion, ethephon, DPCP and paraoxon-methyl; - toxic organophosphorus warfare compounds, notably those banned by the Organisation for the Prohibition of Chemical Weapons (OPCW), such as G-agents, V-agents, e.g. sarin, tabun, soman, VX, methyl(l-(diethylamino)ethylidene)phosphonamidofluoridate, ethyl(l-(diethylamino)ethylidene)phosphonamidofluoridate,

[0131] methyl (bis(diethylamino)methylene)phosphoramidofluoridate, VX or No-vitchoks (A-230, A-232, A-234, A-242, etc.); - toxic industrial chemical compounds, such as L1 (Lewisite), HD (sulfur mustard gas), Cl (Clark 1), C2 (Clark 2), HN3 (nitrogen mustard gas); - sulphide compounds, such as sulphur mustard, a toxic war compound; - nitrogen compounds, such as nitrogen mustard gas, also a toxic war compound; - arsenic compounds, such as lewisite, diphenylchlorarsine, diphenylcya-noarsine, all also toxic war compounds,

[0132] The detection system according to the invention, and the method which implements it, find a particularly advantageous application in the following contexts: - in the event of an accident or criminal act involving a toxic NRBC-E substance, spreading into the environment; - for the identification of old stocks, for example old plant protection product solutions, - in post-contamination, for example for the detection or even identification of a chemical threat of the organophosphorus type.

[0133] The characteristics and advantages of the invention will appear more clearly in the light of the examples of implementation below, provided for purely illustrative purposes and in no way limiting the invention, with the support of figures 1 to 15, in which:

[0134] [Fig-1] [Fig.l] shows images of strips in accordance with the invention bearing respectively particles of different types impregnated with the compound 2,4-NMe2 SQ, in a / under UV lamp at 312 nm, and in b / under visible light.

[0135] [Fig.2] [Fig.2] represents the fluorescence spectra obtained at 310 nm for the strips of [Fig.l].

[0136] [Fig.3] [Fig.3] shows images of strips in accordance with the invention respectively carrying particles of different types impregnated with the compound 4-NMe2SPy, in a / , in the initial state, under a UV lamp at 312 nm, and in b / and c / , in the presence of malathion, under a UV lamp at 312 nm (b / ) and under visible light (c / ).

[0137] [Fig.4] [Fig.4] shows images of strips in accordance with the invention bearing respectively particles of different types impregnated with the compound 4-NMe2SPy, in a / , in the initial state, under UV lamp at 312 nm, and in b / and c / , in the presence of fenthion, under UV lamp at 312 nm (b / ) and under visible light (c / ).

[0138] [Fig.5] [Fig.5] shows images of strips in accordance with the invention carrying neutral alumina particles impregnated with the compound 2-NMe2SQ, in a / under a UV lamp at 312 nm, and in b / under visible light, in the initial state (Ref.) or in the presence of malathion, fenthion, parathion, paraoxon-methyl or DPCP.

[0139] [Fig.6] [Fig.6] shows images of strips in accordance with the invention carrying silica particles grafted with -NH2 groups impregnated with the compound 2-NMe2SQ, in a / under UV lamp at 312 nm, and in b / under visible light, in the initial state (Ref.) or in the presence of malathion, fenthion, parathion, paraoxon-methyl or DPCP.

[0140] [Fig.7] [Fig.7] shows images of strips in accordance with the invention bearing neutral alumina particles impregnated with the compound 4-NMe2SPy, in a / under UV lamp at 312 nm, and in b / under visible light, in the initial state (Ref.) or in the presence of malathion, fenthion, parathion, paraoxon-methyl or DPCP.

[0141] [Fig.8] [Fig.8] shows images of strips in accordance with the invention bearing neutral alumina particles impregnated with the compound 2,4-NMe2SQ, in a / under UV lamp at 312 nm, and in b / under visible light, in the initial state (Ref.) or in the presence of malathion, fenthion, parathion, paraoxon-methyl or DPCP.

[0142] [Fig.9] [Fig.9] shows images of strips in accordance with the invention bearing silica particles grafted with -NH2 groups impregnated with the compound 2-OMeSQ, in a / under UV lamp at 312 nm, and in b / under visible light, in the initial state (Ref.) or in the presence of malathion, fenthion, parathion, paraoxon-methyl or DPCP.

[0143] [Fig. 10] [Fig. 10] shows images of strips in accordance with the invention carrying silica particles grafted with -NH2 groups impregnated with the compound 4-NMe2SQ, in a / under UV lamp at 365 nm, and in b / under visible light, in the initial state (Ref.) or in the presence of different Novichoks (A-230, A-242, A-232, A-234), G-agents (GA and GB), V-agents (VX) and chemical toxins (Ll, HD, Cl).

[0144] [Fig. 11] [Fig. 11] shows images of strips in accordance with the invention carrying basic alumina particles impregnated with the compound 4-NMe2SQ, in a / under UV lamp at 365 nm, and in b / under visible light, in the initial state (Ref.) or in the presence of different Novichoks (A-230, A-242, A-232, A-234), G-agents (GA and GB), V-agents (VX) and chemical toxins (Ll, HD, Cl).

[0145] [Fig. 12] [Fig. 12] represents the fluorescence spectra obtained at 310 nm for strips in accordance with the invention respectively carrying silica particles and silica particles grafted with -NH2 groups, impregnated with the compound 4-NMe2SPy, before or after placing in the presence of malathion.

[0146] [Fig. 13] [Fig. 13] represents the fluorescence spectra obtained at 310 nm for strips in accordance with the invention respectively carrying neutral alumina particles, basic alumina particles and acid alumina particles, impregnated with the compound 4-NMe2SPy, before or after being placed in the presence of malathion.

[0147] [Fig. 14] [Fig. 14] represents the fluorescence spectra (normalized data) obtained at 310 nm for a strip in accordance with the invention carrying silica particles grafted with -NH2 groups, impregnated with the compound 4-NMe2SPy, before or after placing in the presence of malathion.

[0148] [Fig. 15] [Fig. 15] shows images of different strips conforming to the invention relating to “particles / compound of general formula (I)” pairs different, respectively, “acid alumina / 4-NMe2SPy”, “silica / 4-SMeSQ”, “silica grafted by -NH2 groups / 2-NMe2SQ”, “neutral alumina / 2-NMe2 SQ”, before (“Ref.”) or after (“Malathion”) exposure to a commercial solution of malathion, in a / under UV lamp at 312 nm, and in b / under visible light.

[0149] A / Synthesis of compounds of general formula (I)

[0150] A. 1 / General protocol

[0151] The compounds are prepared as follows: an adequate volume of potassium tert-butoxide (tBuOK) (1.2 eq. for the simply methylated reagents, or 2.4 eq. for the di-methylated reagents) is taken in a glove box into a 100 mL flask under an argon (Ar) atmosphere under anhydrous conditions. The tBuOK is dissolved by adding 5 mL of anhydrous dimethylformamide (DMF) introduced using a syringe.

[0152] A solution of the following reagents: - a nitrogenous aromatic heterocycle (quinoline, pyridine, pyrazine or phenanthroline) methylated or di-methylated (1 eq.), - and a benzaldehyde (1.1 eq. for the methylated heterocycle or 2.2 eq. for the di-methylated heterocycle), in 5 mL of anhydrous DMF, is introduced dropwise onto the tBuOK at room temperature. An instant color change to brown / black is observed.

[0153] The reaction medium is brought to 80°C still under an inert Ar atmosphere, until complete conversion. Monitoring by thin layer chromatography (TLC) (cyclohexane:ethyl acetate EtOAc, 70:30) is carried out. The good conversion of the reaction can be observed in certain cases by evolution of the color of the mixture, generally from yellow to red.

[0154] The reaction is stopped by adding water (10 to 20 mL) directly into the reaction medium. The precipitate thus formed is isolated by Buchner filtration and washed. The compounds are obtained pure without purification or by recrystallization. The specifications specific to each of the compounds obtained are detailed below.

[0155] A.2 / (E)-2-[(p-(dimethylamino)styryl]quinoline (2-NMe2SO) This compound, of formula:

[0156] [Chem.20]

[0157] is obtained from the reaction between quinaldine (570 μL; 4 mmol; 1 eq.), p-(dimethylamino)benzaldehyde (0.69 g, 4.4 mmol; 1.1 eq.) in the presence of tBuOK (0.55 g; 4.8 mmol; 1.2 eq.) in DMF (10 mL). The reaction is brought to 60°C under an inert Ar atmosphere until complete conversion (1 h). The reaction is stopped by adding 20 mL of distilled water to the reaction mixture. The yellow precipitate thus formed is washed with water and then with cyclohexane. The product is obtained pure after recrystallization from methanol in the form of fluorescent yellow needles (632.5 mg; 73.5%). Tf: 177°C 'H NMR (CDC13, 400 MHz): ô (ppm) 8.065 (2H, m), 7.754 (1H, d, J = 8.04 Hz),

[0158] 7.679 (1H, t, J = 7.67 Hz), 7.654 (1H, d, J = 8.8 Hz), 7.62 (1H, d, J = 16.8 Hz), 7.547 (2H, d, J = 8.8 Hz), 7.455 (1H, t, J = 7.48 Hz), 7.233 (1H, d, J = 16.6 Hz), 6.735 (2H, d, J = 8.88 Hz), 3.019 (6H, s, -NMe2) 13C NMR (CDC13, 400 MHz): ô (ppm) 156.887, 150.836, 136.194, 135.131, 129.669, 128.689, 127.457, 127.022, 125.672, 124.632, 124.185, 118.975, 112.221, 40.327 IR (ATR, v cm1): 3032.30 (w), 2886.33 (w), 2808.34 (w), 1599.03 (m), 1573.40 (m), 1502.91 (m), 1443.71 (m), 1355.88 (m), 1301.32 (m), 1237.51 (m), 1212.46 (m), 1185.75 (m), 1063.96 (m), 1010.61 (w), 975.62 (m), 953.88 (w), 831.84 (m), 811.17 (m), 800.54 (m), 764.88 (s), 753.78 (s) HRMS (ASAP) m / z calculated for [M+H]+ C19H19N2 275.15427; 275.1546 found.

[0159] A.3 / (E)-2-stvrvlquinoline (2-H SO) This compound, of formula:

[0160] [Chem.21]

[0161] is obtained from the reaction between quinaldine (285 pL; 2 mmol; 1 eq.), benzaldehyde (235 pL, 2.2 mmol; 1.1 eq.) in the presence of tBuOK (275 mg; 2.4 mmol; 1.2 eq.) in DMF (5 mL). The reaction is brought to 80°C under an inert Ar atmosphere until complete conversion (1 h). The reaction is stopped by adding 10 mL of distilled water to the reaction mixture. The yellow precipitate thus formed is washed with water. The product is obtained without purification in the form of a fluorescent yellow powder (334.6 mg; 78.4%). Tf: 98.5°C 'H NMR (CDC13, 400 MHz): ô (ppm) 8.116 (2H, dd, J = 8.52 Hz), 7.792 (1H, d,

[0162] J = 8.16 Hz), 7.677 (5H, m), 7.504 (1H, t, J = 7.20 Hz), 7.409 (3H, m), 7.331 (1H, t, J = 7.28 Hz) 13C NMR (CDC13, 400 MHz): ô (ppm) 156.011, 148.26, 136.539, 136.388, 134.489, 129.781, 129.205, 129.013, 128.821, 128.663, 127.521, 127.371, 127.294, 126.204, 119.275 IR (ATR, v cm-'): 3056.84 (w), 3032.36 (w), 1961.62 (w), 1610.63 (m), 1593.25 (m), 1573.17 (m), 1551.27 (m), 1501.67 (m), 1444.14 (m), 1427.26 (m), 1314.36 (m), 1202.46 (m), 1117.56 (m), 1070.48 (m), 964.24 (s), 823.62 (s), 788.02 (s), 744.06 (s), 689.69 (s) HRMS (ASAP) m / z calculated for [M+H]+ C17H14N 232.11207; 232.1120 found.

[0163] A.4 / (E)-2-(p-methylstyryl)quinoline (2-Me SO) This compound, of formula:

[0164] [Chem.22]

[0165] is obtained from the reaction between quinaldine (285 pL; 2 mmol; 1 eq.), tolualdehyde (233 pL, 2.2 mmol; 1.1 eq.) in the presence of tBuOK (275 mg; 2.4 mmol; 1.2 eq.) in DMF (5 mL). The reaction is brought to 80°C under an inert Ar atmosphere until complete conversion (2 h). The reaction is stopped by adding 10 mL of distilled water to the reaction mixture. The yellow precipitate thus formed is washed with water. The product is obtained without purification in the form of a fluorescent yellow powder (370.6 mg; 75.5%). Tf: 122°C 'H NMR (CDC13, 400 MHz): ô (ppm) 8.101 (2H, dd, J = 8.49 Hz), 7.782 (H, d,

[0166] J = 7.84 Hz), 7.686 (H, m), 7.546 (H, d, J = 8.03 Hz), 7.493 (H, t, J = 7.56 Hz), 7.374 (2H, d, J = 16.34 Hz), 7.216 (2H, d, J = 7.9 Hz), 2.386 (3H, s, -Me) 13C NMR (CDC13, 400 MHz): ô (ppm) 156.241, 148.292, 138.771, 136.301, 134.454, 133.783, 129.719, 129.553, 129.167, 128.066, 127,500, 127,307, 127,233, 126,073, 119,217, 21,383. IR (ATR, v cm1): 3029.92 (w), 1695.38 (w), 1637.13 (w), 1611.50 (w), 1591.24 (m), 1550.48 (m), 1502.93 (m), 1453.76 (w), 1424.48 (m), 1303.81 (m), 1178.01 (m), 1117.53 (m), 981.54 (m), 970.61 (m), 828.55 (s), 750.33 (s) HRMS (ASAP) m / z calculated for [M+H]+ C18H16N 246.12772; 246.1278 found.

[0167] A.5 / (E)-2dn4incthoxv)stvrvl lauinolcinc (2-OMe SOI This compound, of formula:

[0168] [Chem.23]

[0169] is obtained from the reaction between quinaldine (285 pL; 2 mmol; 1 eq.), anisaldehyde (282 pL, 2.2 mmol; 1.1 eq.) in the presence of tBuOK (275 mg; 2.4 mmol; 1.2 eq.) in DMF (5 mL). The reaction is brought to 80°C under an inert Ar atmosphere until complete conversion (2 h and 30 min). The reaction is stopped by adding 10 mL of distilled water to the reaction mixture. The precipitate thus formed is washed with water. The product is obtained without purification in the form of a white powder (421.2 mg; 80.6%). Tf: 122°C 'H NMR (CDC13, 400 MHz): ô (ppm) 8.091 (2H, dd, J = 8.54 Hz), 7.774 (H, d,

[0170] J = 8.04 Hz), 7.697 (1H, t, J = 7.4 Hz), 7.647 (1H, d, J = 16.0 Hz), 7.645 (1H, s), 7.591 (2H, d, J = 8.723 Hz), 7.483 (1H, t, J = 7.45 Hz), 7.289 (1H, d, J = 16.3 Hz), 6.940 (2H, d, J = 8.72 Hz), 3.852 (3H, s, -OMe) 13C NMR (CDC13, 400 MHz): ô (ppm) 160.152, 156.361, 148.269, 136.275, 134.112, 129.705, 129.328, 129.082, 128.669, 127.499, 127,234, 126,855, 125,968, 119,157, 114,287, 55,366 IR (ATR, v cm1): 2999.58 (w), 2836.14 (w), 1594.28 (s), 1551.54 (m), 1507.61 (s), 1456.50 (m), 1429.61 (m), 1301.70 (m), 1253.49 (s), 1173.37 (s), 1026.07 (s), 970.69 (s), 830.96 (s), 818.73 (s), 752.17 (s) HRMS (ASAP) m / z calculated for [M+H]+ Ci8Hi6NO 262.12264; 262.1227 found.

[0171] A.6 / (E)-2-[p-(methvlthio)stvrvl]quinoline (2-SMe SO) This compound, of formula:

[0172] [Chem.24]

[0173] is obtained from the reaction between quinaldine (294 pL; 2.2 mmol; 1 eq.), p- (methylthio)benzaldehyde (293 pL, 2.2 mmol; 1 eq.) in the presence of tBuOK (275 mg; 2.2 mmol; 1.2 eq.) in DMF (5 mL). The reaction is brought to 80°C under an inert Ar atmosphere until complete conversion (4 h). The reaction is stopped by adding 10 mL of distilled water to the reaction mixture. The yellow precipitate thus formed is washed with water. The product is obtained without purification in the form of a white powder (421.3 mg; 75.9%). Tf: 150.5°C 'H NMR (CDC13, 400 MHz): ô (ppm) 8.104 (2H, dd, J = 13.95 Hz & 8.56 Hz), 7.782 (1H, d, J = 8.1 Hz), 7.707 (1H, t, J = 7.9 Hz), 7.649 (2H, m), 7.562 (2H, d, J = 8.13 Hz), 7.496 (1H, t, J = 7.5 Hz), 7.356 (1H, d, J = 16.3 Hz), 7.27 (2H, d, J = 8.13 Hz), 2.52 (3H, s, -SMe) 13C NMR (CDC13, 400 MHz): ô (ppm) 155.943, 139.549, 136.513, 134.075, 133.264, 129.883, 128.997, 127.999, 127.521, 127.313, 126.665, 126.214, 124.099, 119.558, 119.245, 15.537 IR (ATR, v cm1): 3066.10 (w), 3023.47, 2912.29 (w), 1627.57 (w), 1609.52 (w), 1588.91 (m), 1552.85 (m), 1498.78 (m), 1402.79 (m), 1312.84 (m), 1186.09 (m), 1094.81 (m), 964.43 (s), 820.77 (s), 756.97 (s) HRMS (ASAP) m / z calculated for [M+H]+ Cj8H16NS 278.0998; 278.0996 found.

[0174] A.7Z fE)-2-fp-bromostyryl)quinoline 12-BrSO) This compound, of formula:

[0175] [Chem.25]

[0176] is obtained from the reaction between quinaldine (442 μL; 3 mmol; 1 eq.), p-bromobenzaldehyde (642.7 mg, 3.3 mmol; 1.1 eq.) in the presence of tBuOK (412.2 mg; 3.6 mmol; 1.2 eq.) in DMF (7.5 mL). The reaction is brought to 80°C under an inert Ar atmosphere until complete conversion (2 h). The reaction is stopped by adding 20 mL of distilled water to the reaction mixture. The precipitate thus formed is washed with water. The product is obtained pure by recrystallization from cyclohexane in the form of white flakes (426.7 mg; 45.9%). Tf: 135.5°C 'H NMR (CDC13, 400MHz): ô (ppm) 8.17 (1H, d, J = 8.56 Hz), 8.11 (1H, d, J = 8.48 Hz), 7.82 (1H, dd, J = 8.2 & 1 Hz), 7.74 (1H, ddd, J = 8.4, 6.9 & 1.5 Hz), 7.68 (1H, d, J = 8.5 Hz), 7.67 (1H, d, J = 16.4 Hz), 7.573-7.519 (5H, m), 7.42 (1H, d, J = 16.3 Hz) 13C NMR (CDC13, 400 MHz): ô (ppm) 155.594, 148.288, 136.48, 135.509, 133.09, 131.982, 129.87, 129.64, 129.25, 128.69, 127.543, 127.435, 126.348, 122.552, 119.395 IR (ATR, v cm1): 3043.88 (w), 1901.05 (w), 1612.61 (m), 1588.08 (m), 1546.86 (m), 1501.57 (m), 1484.82 (m), 1426.60 (m), 1398.49 (m), 1068.66 (m), 1004.06 (m), 967.57 (s), 819.20 (s), 743.35 (s), 490.06 (s) HRMS (ASAP) m / z calculated for [M+H]+ C17H13NBr 310.02259; 310.0225 found.

[0177] A.8 / (E)-4-rp-(dimethylamino)styryl1quinoline (4-NMe2SO) This compound, of formula:

[0178] [Chem.26]

[0179] is obtained from the reaction between 4-methylquinoline (557 μL; 4 mmol; 1 eq.), p-(dimethylamino)benzaldehyde (345 mg, 4.4 mmol; 1.1 eq.) in the presence of tBuOK (550 mg; 4.8 mmol; 1.2 eq.) in DMF (10 mL). The reaction is brought to 80°C under an inert Ar atmosphere until complete conversion (6 h). The reaction is stopped by adding distilled water to the reaction mixture. The precipitate thus formed is washed with water / EtOH. The product is obtained pure after recrystallization from MeOH in the form of yellow crystals (417.2 mg; 84.3%). Tf: 140°C 'H NMR (CDC13, 400MHz): ô (ppm) 8.850 (1H, d, J = 4.8 Hz), 8.254 (1H, d, J = 8.0 Hz), 8.134 (1H, d, J = 8.4 Hz), 7.723 (1H, t, J = 7.04 Hz), 7.618 (1H, d, J = 16.49 Hz), 7.577 (2H, m), 7.538 (2H, d, J = 8.76 Hz), 7.331 (1H, d, J = 15.93 Hz), 6.753 (2H, d, J = 8.84 Hz), 3.038 (6H, s, -NMe2) 13C NMR (CDC13, 400 MHz): ô (ppm) 150.893, 150.057, 135.416, 129.924, 129.198, 128.509, 126.45, 126.17, 124.759, 123.564, 117.629, 116.155, 112.243, 40.339 IR (ATR, v cm1): 3032.30 (w), 2886.33 (w), 2808.34 (w), 1599.03 (m), 1573.40 (m), 1502.91 (m), 1443.71 (m), 1355.88 (m), 1185.75 (m), 953.88 (m), 753.78 (s) HRMS (ASAP) m / z calculated for [M+H]+ C19H19N2 275.15427; 275.1545 found.

[0180] A.9 / (EE)-2.4-bis[p-(dimethvlamino)stvryl]quinoline (2.4-NMe2SO) This compound, of formula:

[0181] [Chem.27]

[0182] is obtained from the reaction between 2,4-dimethylquinoline 46a (322 μL; 2 mmol; 1 eq.), p-(dimethylamino)benzaldehyde (690 mg; 4.4 mmol; 2.2 eq.) in the presence of tBuOK (550 mg; 4.8 mmol; 2.4 eq.) in DMF (10 mL). The reaction is carried out at 80°C under an inert Ar atmosphere until complete conversion (3 h). The reaction is stopped by adding 10 mL of distilled water to the reaction mixture. The precipitate thus formed is filtered. The product is obtained pure after multiple washes with EtOAc in the form of a yellow-orange solid (388.9 mg; 46.5%). Tf: 168°C 'H NMR (CDC13, 400 MHz): ô (ppm) 8.154 (1H, d, J = 8.3 Hz), 7.823 (1H, s), 7.704 (1H, d, J = 16.3 Hz), 7.679 (1H, t, J = 7.4 Hz), 7.589 (1H, d, J = 15.9 Hz), 7.569 (4H, t, 8.7 Hz), 7.481 (1H, t, J = 7.5 Hz), 7.367 (1H, d, J = 15.9 Hz), 7.285 (1H, d, J = 16.2 Hz), 6.749 (4H, t, J = 8.7 Hz), 3.036 (6H, s), 3.021 (6H, s) 13C NMR (CDC13, 400 MHz): ô (ppm) 150.882, 135.344, 129.634, 128.829, 128.54, 125.46, 125.373, 124.872, 124.711, 123.44, 118.094, 114.113, 112.273, 112.228, 107.871, 40.342 IR (ATR, v cm-'): 3027.49 (w), 2986.77 (w), 2894.47 (w), 2801.05 (w), 1603.33 (s), 1575.84 (s), 1523.15 (s), 1358.62 (s), 1325.92 (m), 1185.67 (s), 1168.20 (m), 958.56 (s), 805.59 (s), 764.15 (s) HRMS (ASAP) m / z calculated for [M+H]+ C29H30N3 420.24342; 420.2439 found.

[0183] A.10 / (E)-4-[(p-(dimethvlamino)stvrvl]pvridine (4-NMe2SPv) This compound, of formula:

[0184] [Chem.28]

[0185] is obtained from Sigma-Aldrich (CAS: 889-36-1; ref. 394211-1G, lot# 04903KEV). The purity of the product is specified at 95%.

[0186] B / Impregnation of the particles by the compounds of general formula fl)

[0187] The general operating protocol for impregnating particles with compounds of general formula (I) is as follows: - weighing of the particle powder in a flask; - weighing of the quantity of compound required (0.1% by mass of compound relative to the mass of powder); - addition of a solvent (absolute ethanol) allowing the solubilization of the compound and so as to have a concentration of approximately 5 mg / 20 mL; - pouring the compound solution into the flask onto the powder and rinsing the pillbox several times and pouring the rinsing solvent into the flask; - depending on the appearance of the powder in the flask, add as much solvent as necessary to wet and suspend the powder; - three-stage evaporation: rotation in the water bath (38°C) of the rotary evaporator for 5 min to homogenize the suspension in the flask; slow pressure reduction to 200 mbar to slowly distill the solvent; when the powders begin to group together to form a ring which attaches to the wall of the flask, the pressure is reduced more quickly until complete drying.

[0188] The different particles used for the tests are as follows: - SiO2, silica having an average particle size of 2-25 pm with a pore size of 60Å for a pore volume of 0.75 cm2 / g, supplied by Aldrich under the product reference 288500-1KG - this silica is designated “@SiO2” herein; - SiO2-NH2, functionalized silica having an average particle size of 40-75 pm with a pore size of 110 Å, supplied by Aldrich under product number 79297-100G (from lot#BCCF5116) - this silica is designated “@SiO 2-NH2” herein; - Al2O3-neutral, an activated, neutralized alumina pH 7.0 + / - 0.5 (in water), Brockmann I, standard grade, having a pore size of 58 Å, a particle size between 40-160 pm (205 m2 / g), supplied by Aldrich under product number 199974-1KG (from lot STBB1977M9) - this alumina is designated "@A12O3 n." herein; - Al2O3-basic, activated alumina, basified pH 9.5 + / - 0.5 (in water), Brockmann I, standard grade, having a pore size of 58 Å, a particle size of 150 mesh (205 m2 / g), supplied by Aldrich under product number 199443-1KG (from lot #S32206-016) - this alumina is designated "@ A12O3 b." herein; - Al2O3-acid, activated alumina, acidified pH 4.5 + / - 0.5 (in water), Brockmann I, standard grade, having a pore size of 58 Å, a particle size between 50-300 mesh (155 m2 / g), supplied by Aldrich under product number 199966-1KG (from lot #BCD3970) - this alumina is designated "@A12O3 a." herein.

[0189] C / Preparation of a coating paste

[0190] The general protocol for preparing a paste, called coating paste, based on particles impregnated with a compound of general formula (I), and intended for deposition on a support, is as follows.

[0191] A solution of polystyrene-block-poly(ethylene-ran-butylene)-block-polystyrene (PSPEPB) polymer binder is made from 11.5% PSPEPB, 61.5% decane and 27% cyclohexane. The percentages used correspond to mass percentages. To make 50 g of solution, 5.75 g of PSPEPB, 13.5 g of cyclohexane and 30.75 g of decane are used. The prepared solution is homogenized in an ultrasonic bath for 1 hour 30 minutes at room temperature. It can be used as is after complete dissolution of the PSPEPB.

[0192] The particles impregnated with compound are introduced into this solution, at a rate of 1.3 g of impregnated particles for 2.4 g of PSPEPB solution, and the whole is mixed.

[0193] D / Coating the coating paste on a support

[0194] The general protocol for coating the coating paste on the support is as follows.

[0195] The support is a flat strip of chromatography paper (Whatman 470x570 mm, cellulose grade 4 CHR, e=0.21 mm, ref.3004-917, lot # 17108889).

[0196] The coating is carried out by scraping the coating paste onto the surface of the support using an Elcometer 4340 motorized film applicator system. The spreading is carried out homogeneously. The deposit thickness is set to 10 μm and the coating speed is adjusted to 4.

[0197] The particles impregnated with the compound of general formula (I) are thus immobilized on the support, and protected from aqueous substances and any other substance external factors to which the system is likely to be exposed and which could impact its proper conservation.

[0198] For these examples, each pair “particles of the same type / same compound of general formula (I)” is deposited on an individual strip which is specific to it. The different strips are assembled on a common flat base.

[0199] E / Tests for the detection / identification of analytes

[0200] For these tests, the colorimetric reading is carried out by visual observation. The fluorescence reading is carried out by visual observation, under an ultraviolet (UV) lamp emitting at a wavelength of 312 nm or 365 nm, or using a portable spectrometer at an excitation wavelength of 310 nm.

[0201] The optical properties, both colorimetric and fluorimetric, of each strip used are known in its initial state, before contact with the analyte(s) to be detected.

[0202] As an example, [Fig.l] shows the visual appearance of strips based on different types of particles impregnated with the compound 2,4-NMe2SQ, in a / , observed under the UV lamp at 312 nm, and in b / , in visible light. [Fig.2] shows the fluorescence spectra obtained with the spectrometer at 310 nm. It is observed that the optical properties of the strips vary depending on the type of particles used.

[0203] For each of the above examples, the analyte is brought into contact with the strip by depositing 1.2 μL of pure liquid analyte with a micropipette onto the surface of the strip coated with the particles in accordance with the invention, impregnated with a compound of general formula (I). The observation of the optical properties is carried out 1 h after this deposition.

[0204] E. 1 / Test 1 - detection of malathion

[0205] The compound used is 4-NMe2SPy. The 5 types of particles above are tested. The fluorescence reading is carried out by visual observation, under an ultraviolet (UV) lamp emitting at a wavelength of 312 nm.

[0206] The results obtained are shown in [Fig.3].

[0207] The 4-NMe2SPy compound impregnated on the different types of particles allows the production of strips ranging from white to orange. The deposition of pure malathion initiates a colorimetric change from yellow to orange. The fluorescence response is more or less intense orange depending on the type of particles used. In this example, the particles to be favored for the detection of malathion by 4-NMe2SPy are @SiO2 and @SiO2-NH2, and @A12O3 a..

[0208] E.2 / Test 2 - detection of fenthion

[0209] The compound used is 4-NMe2SPy. The 5 types of particles above are tested. The fluorescence reading is carried out by visual observation, under an ultraviolet (UV) lamp emitting at a wavelength of 312 nm.

[0210] The results obtained are shown in [Fig.4].

[0211] The 4-NMe2SPy compound impregnated on the different types of particles allows the production of substrates with colors ranging from white to orange. The deposition of pure fenthion initiates a colorimetric change from pale yellow to orange. The fluorescence response is variable in color to opaque, more or less intense depending on the type of particles used. In this example, the particles to be favored for the detection of fenthion with 4-NMe2SPy are @SiO2 and @SiO2-NH2, and @A12O3 n..

[0212] E.3 / Test 3 - detection of a plurality of organophosphorus analytes

[0213] The compound used is 2-NMe2SQ. The particles are neutral alumina @A12O3 n.. The fluorescence reading is carried out by visual observation, under an ultraviolet (UV) lamp emitting at a wavelength of 312 nm.

[0214] The following analytes are placed in the presence of the strips: malathion, fenthion, parathion, paraoxon-methyl, diphenyl chlorophosphate (DPCP).

[0215] The results obtained are shown in [Fig.5].

[0216] The introduction of the strips with the pure analytes initiates a colorimetric change of yellow or pink color depending on the analyte. The fluorescence response is also of variable color: green for malathion and fenthion, black / opaque for parathion and paraoxon-methyl or purple for DPCP.

[0217] These results show that this compound / particle pair allows selective detection of DPCP.

[0218] We also observe similar and characteristic behaviors (characteristic black spot observable by UV lamp) of parathion and paraoxon-methyl. This “particle / compound” pair thus makes it possible to precisely detect organophosphorus compounds containing a para-nitrophenol group.

[0219] E.4 / Test 4 - detection of a plurality of organophosphorus analytes

[0220] The compound used is 2-NMe2SQ. The particles are grafted silica @SiO2 -NH2. The fluorescence reading is carried out by visual observation, under an ultraviolet (UV) lamp emitting at a wavelength of 312 nm.

[0221] The following analytes are placed in the presence of the strips: malathion, fenthion, parathion, paraoxon-methyl, diphenyl chlorophosphate (DPCP).

[0222] The results obtained are shown in [Fig.6].

[0223] The presence of the strips with the pure analytes initiates a colorimetric change of yellow or pink color depending on the analyte deposited. The fluorescence response is also of variable color: light green for malathion, dark green for fenthion, black / opaque for parathion and paraoxon-methyl or purple for DPCP. The yellow color for paraoxon-methyl obtained in colorimetry allows the differentiation of parathion and paraoxon-methyl.

[0224] These results show that this “particle / compound” pair allows detection selective of fenthion (no colorimetric response but fluorogenic response: green coloration under UV lamp) and malathion (pink spot and fluorogenic response: light green coloration).

[0225] E.5 / Test 5 - detection of a plurality of organophosphorus analytes

[0226] The compound used is 4-NMe2SPy. The particles are neutral alumina @A12O 3 n. The fluorescence reading is carried out by visual observation, under an ultraviolet (UV) lamp emitting at a wavelength of 312 nm.

[0227] The following analytes are placed in the presence of the strips: malathion, fenthion, parathion, paraoxon-methyl, diphenyl chlorophosphate (DPCP).

[0228] The results obtained are shown in [Fig.7].

[0229] The presence of the strips with the pure analytes initiates a colorimetric change of orange color more or less intense depending on the analyte deposited. The fluorescence response is also of variable color: invisible for malathion, grayish for fenthion, black / opaque for parathion and paraoxon-methyl or grayish for DPCP. The pronounced orange color observed for paraoxon-methyl in colorimetry allows its identification in comparison with its fluorescence response identical to that observed for parathion.

[0230] E.6 / Test 6 - detection of a plurality of organophosphorus analytes

[0231] The compound used is 2,4-NMe2SQ. The particles are neutral alumina @A12 O3 n. The fluorescence reading is carried out by visual observation, under an ultraviolet (UV) lamp emitting at a wavelength of 312 nm.

[0232] The following analytes are placed in the presence of the strips: malathion, fenthion, parathion, paraoxon-methyl, diphenyl chlorophosphate (DPCP).

[0233] The results obtained are shown in [Fig.8].

[0234] The presence of the strips with the pure analytes initiates a very variable colorimetric change of yellow (fenthion and parathion), pink (malathion), brown (paraoxon-methyl) or purple (DPCP). The fluorescence response is also of variable color: yellow for malathion and fenthion, non-existent for parathion and paraoxon-methyl or green / blue for DPCP.

[0235] These results show that this “particle / compound” pair allows selective detection of DPCP (characteristic bluish response under UV lamp) as well as malathion (pink spot observable in visible light coupled with a pronounced yellow fluorogenic response).

[0236] E.7 / Test 7 - detection of a plurality of organophosphorus analytes

[0237] The compound used is 2-OMeSQ. The particles are grafted silica @SiO2 -NH2. The fluorescence reading is carried out by visual observation, under an ultraviolet (UV) lamp emitting at a wavelength of 312 nm.

[0238] The following analytes are placed in the presence of the strips: malathion, fenthion, parathion, paraoxon-methyl, diphenyl chlorophosphate (DPCP).

[0239] The results obtained are shown in [Fig.9].

[0240] The presence of the strips with the pure analytes initiates a colorimetric change only for paraoxon-methyl (yellow) and DPCP (orange). The fluorescence response is of variable color: almost non-existent (bluish gray) for malathion and fenthion, black / opaque for parathion and paraoxon-methyl or orange for DPCP.

[0241] These results show that this “particle / compound” pair allows selective detection of DPCP (characteristic orange response under UV lamp) as well as paraoxon-methyl (characteristic response distinguishing it from parathion).

[0242] E.8 / Test 8 - detection of a plurality of toxic NRBC-E analytes

[0243] The compound used is 4-NMe2SQ. The particles are grafted silica @SiO2 -NH2. The fluorescence reading is carried out by visual observation, under an ultraviolet (UV) lamp emitting at a wavelength of 365 nm.

[0244] The analytes placed in the presence of the strips are organophosphorus compounds of the NRBC-E type: agents-A (Novichoks: A-230, A-232, A-234 and A-242), agents-G (tabun (GA) and sarin (GB)), agents-V (S-[2-(diisopropylamino)ethyl]methylphosphonothioate o-ethyl (VX)) and several chemical toxicants (2-chloroethenyldichloroarsine, or Lewisite (Ll), dichlorodiethyl sulfide, or sulfur yperite (HD), phenyldichloroarsine, or Clark 1 (Cl)).

[0245] The results obtained are shown in [Fig. 10].

[0246] The presence of the strips with the pure analytes initiates a colorimetric change which is either non-existent (agents-A, agents-V, and GA) or pink in color (GB, Ll, HD and Cl). The fluorescence response (reading at 365 nm) is of variable color: green / yellow (bluish gray) for agents-A, green / bluish for GA, dark blue for GB, light blue for VX, purple for toxicants Ll, ​​HD and CL. A characteristic discoloration is observed in the case of toxicant Ll which allows it to be easily identified compared to the other compounds tested.

[0247] These results show that for this “particles / compound” pair: - Novichoks show a similar response under UV lamp (365 nm); - GB is unequivocally identified by colorimetry and fluorescence (365 nm); - VX is identified under UV lamp (365 nm); - Ll is identified by colorimetry and fluorescence (365 nm).

[0248] E.9 / Test 9 - detection of a plurality of toxic NRBC-E analytes

[0249] The compound used is 4-NMe2SQ. The particles are basic alumina @A12 O3 b. The fluorescence reading is carried out by visual observation, under an ultraviolet (UV) lamp emitting at a wavelength of 365 nm.

[0250] The analytes placed in the presence of the strips are organophosphorus compounds NRBC-E type: A-agents (Novichoks: A-230, A-232, A-234 and A-242), G-agents (GA and GB), V-agents (VX) and several chemical toxins (Ll, HD, Cl).

[0251] The results obtained are shown in [Fig. 11].

[0252] The presence of the strips with the pure analytes initiates a colorimetric change which is either non-existent to pale yellow (agents-A, agents-V, and GA) or intense red (GB) or pink (Ll, HD and Cl). The fluorescence response (reading at 365 nm) is of variable color: intense green / yellow for agents-A, green / bluish for GA, violet / brown for GB, light blue for VX, violet for toxicants Ll, ​​HD and CL. A characteristic discoloration is observed in the case of toxicant Ll which allows it to be easily identified compared to the other compounds tested.

[0253] These results show that for this “particles / compound” pair: - Novichoks show a similar response under UV lamp (365 nm); - GB is unequivocally identified by colorimetry and fluorescence (365 nm); - Ll is identified by colorimetry and fluorescence (365 nm).

[0254] E. 10 / Test 10 - detection of malathion by portable spectrometer

[0255] The compound used is 4-NMe2SPy. All of the particles mentioned above are tested.

[0256] The fluorescence spectra obtained using the spectrometer, before and after exposure to malathion, are shown in [Fig. 12] for silicas and in [Fig. 13] for alumina, respectively before and after exposure to malathion.

[0257] It is observed that malathion is easily identifiable, because after reading the fluorescence it causes an increase in the intensity of the signal regardless of the type of particle used. A shift towards stronger wavelengths is also observed following exposure to malathion.

[0258] Detection can be refined by calculating the shift towards higher (or lower) wavelengths. This AX value, expressed in nm, is specific to each of the analytes tested (signature of an analyte) and makes it possible to obtain a signal / detected analyte correspondence. This method allows the precise identification of one or more analytes.

[0259] The normalization of the signal obtained in the present example of malathion makes it possible to highlight the phenomenon of displacement of the signal after exposure to malathion.

[0260] As an example, [Fig. 14] shows the normalized fluorescence spectra obtained for the @SiO2-NH2 particles. A shift towards higher wavelengths AX = 29 nm caused by the exposure of the strip to malathion is measured.

[0261] E. 11 / Test 11 - detection of malathion by various pairs of “particles of the same type / same compound of general formula (I) »

[0262] A commercial solution of malathion (insecticide oil for cochineals; Bayer), formerly marketed, is deposited pure on the following different types of “particles of the same type / same compound of general formula (I)” pairs. The fluorescence is read by visual observation, under an ultraviolet (UV) lamp emitting at a wavelength of 312 nm.

[0263] The results obtained are shown in [Fig. 15]. More particularly: - the @Al2O3b. / 4-NMe2SPy couple generates a zero colorimetric response and an orange fluorescence response; - the @SiO2 / 2-SMeSQ couple generates a yellow colorimetric response and a green fluorescence response; - the @SiO2-NH2 / 2-NMe2SQ couple generates a pink colorimetric response and an opaque violet fluorescence response; - the @Al2O3n. / 2-NMe2SQ couple generates a pink colorimetric response and a purple fluorescence response.

[0264] E. 12 / Test 12 - detection of malathion by various pairs “particles of the same type / same compound of general formula fl)”

[0265] Obtaining by the method according to the invention, a unique signature for a given analyte, by the implementation of a plurality of pairs “particles of the same type / same compound of general formula (I)”, is demonstrated in this example for the organophosphorus analyte malathion, for the following 6 different pairs: “@SiO2 -NH2 / 4-NMe2SPy”, “@Al2O3b. / 4-NMe2SPy”, “@Al2O3n. / 2,4-NMe2SQ”, “@SiO2 / 2-SMeSQ”, “@A12O3 n. / 2-NMe2SQ”, “@Al2O3a. / 2-NMe2SQ”.

[0266] The results obtained, in terms of colorimetric response and fluorescence response (at 312 nm), are summarized in Table 1 below.

[0267] [Tables 1] Particle / compound @SiO2-NH 2 / 4-NMe2S Py @A12O3 b. / 4-NMe2 SPy @A12O3 n. / 2,4-N Me2SQ @SiO2 / 2- SMeSQ @A12O3 n. / 2-NMe 2sq @A12O3 a. / 2-NMe 2sq Colorimetric response orange orange brown violet pale pink pink Fluorogenic response orange orange yellow yellow green yellow Initial fluorescence peak (nm) 580 588 554 540 507 510 Peak modification by malathion exposure Aug + red shift Aug Aug + red shift Aug + red shift Aug + blue shift Aug AX (nm) 29 - 34 57 -18 -

[0268] Table 1 - optical responses of different pairs “particles of the same type / same compound of general formula (I)” to exposure to malathion - “Aug” indicates an increase in the intensity of the peak, “red shift” indicates a bathochromic shift, and “blue shift” indicates a hypsochromic shift

[0269] All of these data constitute the characteristic signature of malathion with respect to the “particles of the same type / same compound of general formula (I)” pairs used.

[0270] E. 13 / Test 13 - detection of malathion by various pairs “particles of the same type / same compound of general formula (I)”

[0271] The obtaining by the method according to the invention, of a unique signature for a given analyte, by the implementation of a plurality of pairs “particles of the same type / same compound of general formula (I)”, is demonstrated in this example for the organophosphorus analyte fenthion, for the following 3 different pairs: “@A12O3 b. / 2,4-NMe2SQ”, “@Al2O3b. / 2-NMe2SQ”, “@Al2O3n. / 2-NMe2SQ.

[0272] The results obtained, in terms of colorimetric response and fluorescence response (at 312 nm), are summarized in Table 2 below.

[0273] [Tables2] Particle / compound @Al2O3b. / 2,4-NMe2SQ @Al2O3b. / 2-NMe2SQ @Al2O3n. / 2-NMe2SQ Colorimetric response yellow pink - Fluorogenic response yellow green green Initial fluorescence peak (nm) 554 517 510 Peak modification by malathion exposure Blue shift Increase Blue shift

[0274] Table 2 - optical responses of different pairs “particles of the same type / same compound of general formula (I)” to exposure to fenthion - “blue shift” indicates a shift towards the lower wavelengths

[0275] All of these data constitute the characteristic signature of fenthion with respect to the “particles of the same type / same compound of general formula (I)” pairs used.

[0276] E. 14 / Test 14 - detection of DPCP by various pairs of “particles of the same type / same compound of general formula (I) »

[0277] Obtaining by the method according to the invention, a unique signature for a given analyte, by the implementation of a plurality of pairs “particles of the same type / same compound of general formula (I)”, is demonstrated in this example for the organophosphorus analyte DPCP, for the following 6 different pairs: “@SiO2-NH 2 / 4-NMe2SPy”, “@SiO2-NH2 / 2,4-NMe2SQ”, “@Al2O3n. / 2,4-NMe2SQ”, “@SiO2 -NH2 / 2-SMeSQ”, “@Al2O3b. / 2-NMe2SQ”, “@SiO2-NH2 / 2-OMeSQ”.

[0278] The results obtained, in terms of colorimetric response and fluorescence response (at 312 nm), are summarized in Table 3 below.

[0279] [Tables3] Particle / compound @SiO2-NH 2 / 4-NMe2 SPy @SiO2-N h2 / 2,4-NMe2 SQ @ A12O3 n. / 2,4-NMe2 SQ @SiO2-N h2 / 2-SMeSQ @Al2O3b. / 2-NMe2S Q @SiO2-N h2 / 2-OMeS Q Colorimetric response Deco Deco violet yellow pink orange Fluorogenic response pink Blue / green Blue / green yellow pink orange Initial fluorescence peak (nm) 589 490 487 - - 561 Peak modification by malathion exposure Dim + red shift Blue shift Blue shift Aug + red shift Aug + signal at 3 charac. maxima Red shift AX (nm) 38 -46 -33 - - 77

[0280] Table 3 - optical responses of different pairs “particles of the same type / same compound of general formula (I)” to exposure to DPCP - “Decol” indicates a discoloration (white spot), “Dim” indicates a decrease in the intensity of the peak, “Aug” indicates an increase in the intensity of the peak, “red shift” indicates a shift towards the higher wavelengths, and “blue shift” indicates a shift towards the lower wavelengths

[0281] All of this data constitutes the characteristic signature of the DPCP with respect to the “particles of the same type / same compound of general formula (I)” pairs used.

[0282] E. 15 / Test 15 - detection of a plurality of organophosphorus analytes

[0283] The couple “@Al2O3n. / 2-SMeSQ” is used to establish the signatures of the following different organophosphorus analytes: malathion, fenthion, DPCP, parathion and paraoxon-methyl.

[0284] The results obtained, in terms of colorimetric response and fluorescence response (at 312 nm), are summarized in Table 4 below.

[0285] [Tables4] Analyte Malathion Fenthion DPCP Parathion Paraoxon-m ethyl Colorimetric response pink pink pink yellow yellow Fluorogenic response yellow green pink Black / purple Black / purple Initial fluorescence peak (nm) 510 517 multimaxima - - Peak modification by exposure to malathion Aug Aug + red shift Aug + signal at 3 maxima charac. extinction extinction AX (nm) - 7 - - -

[0286] Table 4 - Optical responses of the “@Al2O3n. / 2-SMeSQ” pair to exposure to different organophosphorus analytes - “Aug” indicates an increase in peak intensity, “red shift” indicates a shift towards higher wavelengths

[0287] It is observed that the couple "@Al2O3n. / 2-SMeSQ" allows the detection and identification of malathion, fenthion and DPCP in a precise manner by interpretation of the fluorescence response. The colorimetric method only allows the demonstration of the presence of an organophosphorus compound.

[0288] The colorimetric response of parathion and paraoxon-methyl is not readable in colorimetry. Nevertheless, the study of fluorescence (extinction) makes it possible to demonstrate the presence of a foreign compound, different from malathion, fenthion and DPCP.

[0289] E. 16 / Test 16 - detection of a plurality of organophosphorus analytes by several pairs “particles of the same type / same compound of general formula (I)”

[0290] The detection of a series of organophosphorus compounds: malathion, omethoate, fenthion, parathion and paraoxon-methyl is carried out by the use of two pairs “particles of the same type / same compound of general formula (I)” analyzed in parallel under white light illumination for colorimetric reading and under UV excitation at 312 nm for fluorescence reading: “@SiO2-NH2 / 4-NMe2SQ” and “@SiO2-NH2 / 2-OMeSQ”.

[0291] The results obtained, in terms of colorimetric response and fluorescence response (at 312 nm), are summarized in Table 5 below.

[0292] [Tables5] @SiO2-NH2 / 2-OMeSQ Compound Ref. malathion omethoate fenthion parathion Paraoxon-methyl Colorimetry Blue Blue / grey Blue / grey black black orange Fluorescence Pale yellow - - - yellow yellow @SiO2-NH2 / 4-NMe2SQ Compound Ref. malathion omethoate fenthion parathion Paraoxon-methyl Colorimetry Yellow pink pink Pale pink yellow brown Fluorescence Grey pink pink Orange / pink Opaque grey Violet / opaque grey

[0293] Table 5 - optical responses of the pairs “@SiO2-NH2 / 4-NMe2SQ” and “@SiO2 -NH2 / 2-OMeSQ” to exposure to different organophosphorus analytes - “Ref.” indicates the strip in the initial state

[0294] It is observed that the combination of the two detection pairs allows the precise identification of the pesticides parathion and paraoxon-methyl, which cannot be identified by fluorogenicity alone. The fluorescence response of these two pesticides, which have the common characteristic of comprising a p-nitrophenol group, is characterized by a complete extinction of the initial fluorescence intensity of the strips. Fluorescence reading thus allows the detection of the presence of this category of molecules. The combination of colorimetric reading allows the differentiation of these molecules. Indeed, the pair "@SiO2-NH2 / 2-OMeSQ" generates a yellow colorimetric response only for paraoxon-methyl. The pair "@SiO2-NH2 / 4-NMe2SQ" initiates a unique brown colorimetric response for paraoxon-methyl, and a yellow colorimetric response in the presence of parathion.

[0295] The “@SiO2-NH2 / 2-OMeSQ” pair also makes it possible to discriminate the presence of any other organophosphorus: no colorimetric response is obtained for malathion, omethoate, fenthion and parathion.

[0296] E. 17 / Test 17 - detection of a plurality of NRBC-E toxic analytes by several pairs of “particles of the same type / same compound of general formula (I)”

[0297] In order to refine the detection of Novichoks (A-230, A-232, A-234, A-242), vis- with regard to the compounds GA, GB and VX in particular, the combination of the following pairs can be used: “@Al2O3b. / 4-NMe2SQ” and “@Al2O3a. / 4-NMe2SQ”.

[0298] Indeed, in the context of the detection of NRBC-E toxicants, Novichoks can be confused with GA on the pair “@Al2O3b. / 4-NMe2SQ”. The pair “@A12 O3a. / 4-NMe2SQ” makes it possible to differentiate GA from Novichoks, as shown by the results presented in Table 6 below.

[0299] [Tableauxô] Pair « @Al2O3b. / 4-NMe2SQ » « @ A12O3 a. / 4-NMe2SQ » Lighting White light UV 365 nm White light UV 365 nm GA - Blue / green Orange Blue / green GB Red Violet Pink / red Violet VX - Light blue - Light blue Novichoks - Intense turquoise yellow Intense turquoise

[0300] Table 6 - Optical responses of the pairs “@ Al2O3b. / 4-NMe2SQ” and “@ Al2O3a. / 4-NMe2SQ” to exposure to different NRBC-E analytes

[0301] As can be observed, with respect to the couple “@Al2O3a. / 4-NMe2SQ”, the Novichoks are distinguished from GA (blue / green fluorescence emission under excitation at 365 nm and orange coloration under white light) by an intense turquoise fluorescence emission under excitation at 365 nm and a yellow trace under white light.

[0302] E. 18 / Test 18 - detection of a plurality of toxic NRBC-E analytes by several pairs “particles of the same type / same compound of general formula (I)”

[0303] In order to constitute a complete identification set of the analytes of interest, the impact as well as the absence of impact of the latter on different detection strips can be recorded in a database. In addition, certain redundancies of information make it possible to ensure the reliability of the results.

[0304] In this test, three pairs “particles of the same type / same compound of general formula (I)” were used: - “@SiO2-NH2 / 4-NMe2SQ”, - “@A12O3 b. / 4-NMe2SQ”, - “@A12O3 a. / 4-NMe2SQ”.

[0305] These three pairs involve the same detection indicator 2,4-[4-(dimethylamino)styryl]quinoline (4-NMe2SQ), impregnated on three different types of particles.

[0306] The different strips are placed in the presence of the following analytes: GA, GB, VX, Novichoks (A-230, A-232, A-234, A-242), HD, tris(2-chloroethyl)amine, or nitrogen mustard (HN3), Ll, Cl, diphenylcyanoarsine, or Clark 2 (C2).

[0307] The strips are observed: - under white light using an office scanner, - under UV light at 365 nm using a camera.

[0308] The recovered data are subject to simple observation with the naked eye. It is understood that these data could be digitally processed by colorimetric coordinate readings and that the spectral data could have been collected by a portable spectrophotometer.

[0309] The results obtained are summarized in Table 7 below.

[0310] [Tables7] Particles @SiO2-NH2 @A12O3 b. @A12O3 a. Lighting White light UV 365 nm White light UV 365 nm White light UV 365 nm GA - Pale green X Blue / orange green Blue / green GB pink Dark blue red violet Pink / red violet VX - light blue - light blue - light blue Novichoks - intense turquoise - intense turquoise yellow intense turquoise HD pink pale violet red violet red dark violet HN3 - - orange violet red violet Ll white blue white blue white blue Cl pink - pink blue / violet white blue C2 - - red pink pink / orange -

[0311] Table 7 - optical responses of the pairs “@SiO2-NH2 / 4-NMe2SQ”, “@A12O3 b. / 4-NMe2SQ”, “@A12O3 a. / 4-NMe2SQ” to exposure to different NRBC-E analytes

[0312] It is observed that the signatures of the liquid deposited toxicants (GA, GB, VX, Novichoks, HD, HN3, Ll, Cl, C2) are all different from each other.

[0313] Among the most similar: - Ll and Cl differ in their response under white light on the detection couple “@A12O3 b. / 4-NMe2SQ”. Indeed, L1 causes a white discoloration, while Cl causes a pink coloration; - VX and Novitchoks differ in their fluorescence response under excitation at 365 nm on the three strips used in this example, which makes the interpretation more reliable. Indeed, VX generates a light blue fluorescence emission, while Novitchoks generate an intense turquoise fluorescence emission; - HD and HN3 differ in their response under white light on the detection substrate “@SiO2-NH2 / 4-NMe2SQ”. Indeed, HD causes a pink coloration, while HN3 does not generate any colorimetric shift for this detection pair; - GA and VX differ in their response under white light on the detection pair “@ A12O3 a. / 4-NMe2SQ”, as well as in their fluorescence response under excitation at 365 nm on the three detection pairs used in this example. Indeed, GA generates an orange coloration, while VX does not generate any colorimetric shift on the three detection pairs. In addition, GA generates a pale green or blue / green fluorescence emission, while VX generates a light blue fluorescence emission.

Claims

Claims

1. System for detecting one or more chemical substances, comprising at least one compound of general formula (I): [Chem 1] (I) R? in which Ari represents a nitrogen-containing aromatic heterocycle optionally substituted by one or more linear or branched alkyl radicals, or Ari represents a condensed polycyclic aromatic group containing at least one nitrogen-containing aromatic heterocycle, each of the rings of said condensed polycyclic aromatic group being carbocyclic or nitrogen-containing, and being optionally substituted by one or more linear or branched alkyl radicals, Ri, R2 and R3, identical or different, each represent a hydrogen atom or a group R4 of general formula (II): [Chem 2] c (II) |.............■=='............Aç in which Ar2 represents a phenyl group substituted by a group R5 chosen from a hydrogen atom, a halogen atom, a primary amino group, a hydroxyl group, a sulfhydryl group and a group -R6, -NHR6, -N(R6)2, -OR6 or -SR6, where R6 represents a linear or branched alkyl radical, Ar2 being further optionally substituted by one or more linear or branched alkyl radicals, R1, R2 and R3 not all simultaneously representing a hydrogen atom, and in which each compound of general formula (I) is carried by particles of at least two different types, the particles of the same type and carrying the same compound of general formula (I) being arranged on a solid support distinct from the others.

2. The system of claim 1, wherein in general formula (I), Ari is selected from the groups of general formulas (Ilia), (Illb), (Hic) and (nest): [Chem 3] (IIIa) [Chem 4] ,,N .. (Illb) [Chem 5] ,N„ (IIIc) [Chem 6] (Illd)

3.

4.

5. each of said groups of general formulas (IIIa), (IIIb), (IIIc) and (IIId) being optionally substituted by one or more linear or branched alkyl radicals. System according to claim 1 or 2, wherein, in general formula (II), Ar2 represents a phenyl group substituted by said group R5 in the para position relative to the vinyl bond to Arp System according to any one of claims 1 to 3, wherein, in general formula (I), R2 and R3 represent a hydrogen atom, or R1 and R2 are identical and R3 represents a hydrogen atom, or Rb R2 and R3 are identical. A system according to any one of claims 1 to 4, comprising a plurality of different compounds of general formula (I), each of said compounds being carried by particles of at least two different types.

6. System according to any one of claims 1 to 5, wherein the particles of at least one of said different types of particles are inorganic particles, preferably chosen from silica particles, silica particles grafted with organic groups, alumina particles, zinc oxide particles, titanium oxide particles, diatomaceous earth particles, zeolite particles, geopolymer particles.

7. System according to any one of claims 1 to 6, in which the particles are arranged on said support included in a layer comprising, in addition to these particles, at least one organic binder.

8. A system according to any one of claims 1 to 7, wherein said support is formed of paper.

9. System according to any one of claims 1 to 8, in which the particles of the same type and carrying the same compound of general formula (I) are arranged on a separate support.

10. System according to any one of claims 1 to 8, in which all of the particles are arranged on the same support, the particles of the same type and carrying the same compound of general formula (I) being arranged on a zone distinct from said support.

11. A method of preparing a detection system according to any one of claims 1 to 10, comprising steps of: - preparing a plurality of different compositions each containing, respectively, a compound of general formula (I) carried by particles of a different type of particles, at least one organic solvent, and optionally at least one organic binder, - and depositing each of said compositions on a solid support, separately from each other.

12. Preparation process according to claim 11, according to which the organic solvent(s) are apolar solvents.

13. Preparation process according to claim 11 or 12, according to which the organic solvent(s) are hydrocarbon solvents chosen from saturated aliphatic solvents, aromatic solvents and terpenoid solvents.

14. Preparation process according to any one of claims 11 to 13, according to which the organic binder(s) are polymeric binders, preferably comprising styrenic repeating units, of polydimethylsiloxane type, or of paraffin type.

15. Preparation process according to any one of claims 11 to 14, according to which the deposition of said compositions is carried out respectively on separate supports.

16. Preparation process according to any one of claims 11 to 14, according to which the deposition of said compositions is carried out respectively on distinct zones of the same support.

17. Method for detecting a chemical substance likely to be contained in a medium, comprising steps of: - bringing said medium into contact with all of the particles carrying a compound of general formula (I) of a detection system according to any one of claims 1 to 10; - acquiring the colorimetric response and the fluorogenic response induced by said contact, for each different “particles of the same type / same compound of general formula (I)” pair included in said detection system, - deduction, as a function of all of said colorimetric responses and said fluorogenic responses, of the absence or presence of said substance in said medium.

18. The method of claim 17, wherein said chemical substance is a warfare toxic compound, a chemical industrial toxic compound and / or a pesticide.

19. A method according to claim 17 or 18, wherein said chemical substance is an organophosphorus substance.

20. Kit for detecting one or more chemical substances, comprising: - a detection system according to any one of claims 1 to 10, - a colorimetric and fluorogenic database making it possible to establish the correspondence between the colorimetric responses and the fluorogenic responses observed for each different “particles of the same type / same compound of general formula (I)” pair included in said detection system, and each of said chemical substances.