ES2541980B2 - Solid polymeric materials for the fluorogenic detection of nitroderivative explosives and their use - Google Patents

Abstract

New solid polymeric materials for the fluorogenic detection of nitroderivative explosives based on new vinyl monomers derived from the family of hydroxycoumarins and their complexes with terbium (III) and samarium (III), which act as fluorogenic sensors of nitroderivative explosives such as TNT (2 , 4,6-trinitrotoluene), cyclothrimethylenetrinitramine (RDX) and pentaerythritol tetranitrate (PETN), through the detection of vapors of these compounds.

Description

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SOLID POLYMERIC MATERIALS FOR FLUOROGENIC DETECTION OF NITRO-DERIVED EXPLOSIVES AND USE

THEREOF

DESCRIPTION

OBJECT OF THE INVENTION

The present invention relates to new solid polymeric materials for the fluorogenic detection of nitro-derived explosives based on new vinyl monomers derived from the hydroxycoumarin family and their complexes with terbium (III) and samarium (III), which act as fluorogenic sensors for explosives nitro derivatives, such as TNT (2,4,6-trinitrotoluene), cyclothrimethylenetrinitramine (RDX) and pentaerythritol tetranitrate (PETN), through the detection of vapors of these compounds.

By polymerizing these monomers, films or dense membranes are obtained, by copolymerization of these monomers with others, including polyfunctional monomers, to provide materials with good mechanical properties, both dry and swollen, that behave as solid fluorogenic sensors of vapors of nitroderivative compounds, TNT, RDX and PETN. In addition, the joint use of these sensors in the form of a sensor matrix and the statistical treatment of the data obtained from their use allows the selective detection of these compounds and their differentiation from other similar interferers, such as l-chloro-4- nitrobenzene (C1NB), 2-nitro-m-xylene (NX), 1,3-dinitrobenzene (1,3-DNB), 2-nitrotoluene (2-

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NT), 4-nitrotoluene (4-NT) and 2,4-dinitrotoluene (2,4-DNT). In addition, the joint use of these sensors, in the form of a sensor matrix, and a multivariate data analysis allows the selective detection of these compounds and their differentiation from other similar interferents, as well as the evaluation of the probabilities of committing false positives and false negatives Specifically, regression and classification techniques based on latent variables and / or techniques based on neural networks will be applied to the complete fluorescence spectra.

BACKGROUND OF THE INVENTION

The development of new sensors, chromogenic and fluorogenic, simple, fast and cheap for the

Detection of devices and traces of explosives such as TNT, RDX and PETN, by non-specialized personnel and by conventional techniques (KL Diehl, EV Anslyn, Chem. Soc. Rev. 2013, 42, 8596-8611; DS Moore, Rev. Sci. Instrum. 2004, 75, 2499-2512; J. Cho, R.

Anandakathir, A. Kumar, J. Kumar, P.U. Kurup, Sens. Actuators. B, 2011, 160, 1237-1243) has become a major challenge, due to the increasing globalization of terrorist attacks, both in the detection of dangerous artifacts and the high toxicity of nitro-derived explosives, easily absorbed by the skin and intestinal tract (WD McNally, Toxicity, Industrial medicine, Chicago, IL, 1937).

Among the techniques commonly used in the detection of TNT are ion mobility spectrometry (IMS) (D.S. Moore, Sense Imaging, 2007, 8, 9-38), gas chromatography (GC) and

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High performance liquid chromatography (HPLC) coupled to various equipment such as UV-vis and mass spectrometry (T.F. Jenkins, D.C. Leggett, C.L. Grant, C.F. Bauer, Anal. Chem. 1986, 58, 170-175; R. Bongiovanni,

G.E. Podolak, L.D. Clark, D.T. Scarborough, Am. Ind. Hyg. Assoc. J. 1984, 45, 222-226; D.H. Fine, W.C. Yu,

U.S. Goff, J. Forensic Sci. 1984, 29, 732-746; H.R. Beller, K. Tiemeier, Environ. Sci. Technol. 2002, 36, 2060-2066), precise techniques that require very expensive equipment and technical specialists in this type of analysis, together with the fact of not being able to perform an on-site analysis in the place of interest.

Within the framework of the fluorogenic detection of nitro-derived explosives, the detection of explosive vapors represents an important challenge due to the

low vapor pressures of this family of compounds (R.G. Ewing, M.J. Waltman, D.A. Atkinson, J.W. Grate, P.J. Hotchkiss, TrAC-Trend. Anal. Chem. 2013, 42, 35

48), which increases the difficulty in the development of new materials capable of detecting traces of potentially dangerous compounds through the presence of vapors by variations in their fluorescence (A. Alvarez, A. Salinas-Castillo,

J. M. Costa-Fernandez, R. Pereiro, A. Sanz-Medel, Trac-

Trend Anal. Chem., 2011, 9, 1513-1525; S. W. Thomas, G. D. Joly, T. M. Swager, Chem. Rev. 2007, 107, 1339-1386;

J. M. Garcia, F. C. Garcia, F. Serna, J. L. de la Pena, Polym. Rev. 2011, 51, 341-390; K. J. Albert and D. R.

Walt, 2000, 72, 1947-1955).

Thus, for example, EP0401861 Bl describes a scanning system for detecting

Explosives used for the detection of explosives and other controlled substances such as drugs or narcotics. He

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Scanning system detects the emissions of steam and / or particles of such and reports their presence in an individual or object and its concentration. The scanning system consists of a sample chamber for the collection of steam and / or particle emissions, a concentration and analysis system for the purification of vapor emissions and / or collected particles and the subsequent detailed chemical analysis of said emissions, and a control and data processing system for the control of the entire system.

Thus, in order to facilitate the detection of analytes of interest, the development of molecules and materials that act as chromogenic or fluorogenic sensors is a topic of great scientific and technological relevance.

Therefore, and in order to obtain simple, fast, cheap and easy-to-use sensor materials, it would be advantageous to have dense membranes as sensor materials in the development of this field (JM Garcia, FC Garcia, F. Serna, JL de la Pena, Polym. Rev. 2011, 51, 341-390, S. Vallejos, P. Estevez, FC Garcia, F. Serna, JL de la Pena, Chem. Commun. 2010, 46, 7951-7953, N. San- Jose, J. Soto, Org. Lett. 2007, 9, 2429-2432). It would also be desirable to have solid films that can be easily handled, both dry and wet, in relation to this technology.

The present invention provides novel solid polymeric materials that allow the detection of nitroderivative and explosive compounds (TNT, RDX and PETN) by changes in fluorescence spectra due to the presence of vapors of these compounds.

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The main advantage lies in the preparation of a material that has good physical properties and allows the detection of explosive vapors.

DESCRIPTION OF THE INVENTION

In general, the present invention relates to new polymeric materials for the fluorogenic detection of nitro-derived explosives based on vinyl monomers derived from the hydroxycoumarin family and their complexes with terbium (III) and samarium (III), which act as fluorogenic sensors of Nitroderivative explosives, TNT (2,4,6-trinitrotoluene), cyclothrimethylenetrinitramine (RDX) and pentaerythritol tetranitrate (PETN), in solid form, through the detection of vapors of these compounds.

In a first aspect, the invention relates to new polymeric materials based on vinyl monomers derived from the hydroxycoumarin family and their complexes with terbium (III) and samarium (III), in particular the vinyl monomer derived from a bis-coumarin, specifically N- (4- (bis (4- hydroxy-2-oxocumarin-3-yl) methyl) phenyl) methacrylamide and the complexes with terbium (III) and samarium (III) obtained from this vinyl monomer, as well as a the dense polymeric membranes obtained by copolymerization of this with different monomers, both hydrophilic and hydrophobic, with one or several polymerizable multiple bonds, for the fluorogenic detection of nitroderivative explosive vapors.

In a second aspect, the invention relates to the use of the cited polymeric materials as

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sensors in applications of fluorogenic detection of vapors of nitro-derived explosives.

In the present description, the terms "polymer" and "polymerization" should be understood in the broadest sense thus encompassing "homopolymers and copolymers" and "homopolymerization and copolymerization" respectively.

DESCRIPTION OF THE FIGURES

The present specification is complemented with a set of figures, illustrative and non-limiting of the invention.

Figure 1: Characterization of 3,3 '- ((4-

nitrophenyl) methylene) bis (4-hydroxycoumarin-2-one): (a) chemical structure; (b) infrared spectrum; (c) proton magnetic resonance (1 H NMR); (d) carbon magnetic resonance

(13C NMR).

Figure 2: Characterization of 3,3 '- ((4-

aminophenyl) methylene) bis (4-hydroxycoumarin-2-one): (a) chemical structure; (b) infrared spectrum; (c) proton magnetic resonance (1 H NMR); (d) carbon magnetic resonance

(13C NMR).

Figure 3: Characterization of N- (4- (bis (4-hydroxy-2- oxo-coumarin-3-yl) methyl) phenyl) methacrylamide:

(a) chemical structure; (b) spectrum of

infrared; (c) proton magnetic resonance (1 H NMR); (d) carbon magnetic resonance

(13C NMR).

Figure 4:

Characterization of the complex derived from N- (4- (bis (4-hydroxy-2-oxo-cumarin-3-yl) methyl) -

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Figure 5

Figure 6

Figure 7

Figure 8

phenyl) methacrylamide with terbium (III) and vinyl monomer (I): a) Resonance spectrum

proton magnetics (1H NMR), b) Spectrum of

carbon magnetic resonance (13C NMR) and c) infrared spectrum.

: Characterization of the complex derived from N- (4- (bis (4-hydroxy-2-oxo-cumarin-3-yl) methyl) - phenyl) methacrylamide with samarium (III) and vinyl monomer (la) Magnetic resonance spectrum proton (1H NMR), b) Spectrum of

carbon magnetic resonance (13C NMR) and c) infrared spectrum.

: Characterization of MemI dense membranes (copolymerization of N- (4- (bis (4-hydroxy-2- oxo-coumarin-3-yl) methyl) phenyl) methacrylamide), Memll (copolymerization of the N- complex ( 4- (bis (4-hydroxy-2-oxo-cumarin-3-yl) methyl) - phenyl) methacrylamide) with terbium (III)) and Memlll (copolymerization of the N- complex (4- (bis (4- hydroxy-2-oxo-coumarin-3-yl) methyl) -phenyl) methacrylamide) with samarium (III). (to)

chemical structure (b) Table of data obtained by thermogravimetric analysis (c) FTIR spectra.

: Detection of compound vapors

Nitroderivatives and explosives of the MemI dense membrane by a) analysis of the

variation of its fluorescence spectrum with the exposure time; b) Representation of I / I over time.

: Detection of compound vapors

Nitroderivatives and explosives of the dense membrane Memll by a) analysis of the

variation of its fluorescence spectrum with the exposure time. b) Representation of

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I / I over time.

Figure 9: Detection of vapors of nitroderivative and explosive compounds of the Memlll dense membrane by a) analysis of the variation of its fluorescence spectrum with the exposure time. b) Representation of I / I over time.

DETAILED EXHIBITION OF THE INVENTION

According to the first aspect, the invention relates to new polymeric materials based on vinyl monomers derived from the hydroxycoumarin family and their complexes with terbium (III) and samarium (III), in particular the vinyl monomer

derived from a bis-coumarin, specifically N- (4- (bis (4- hydroxy-2-oxocumarin-3-yl) methyl) phenyl) methacrylamide and

the complexes with terbium (III) and samarium (III) obtained from this vinyl monomer, for the fluorogenic detection of nitro-derived explosive vapors.

Therefore, the invention provides monomers of structure I and complexes obtained with I by interaction with salts of Tb (III) and Sm (III).

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N

HN

I

image 1

The invention also provides polymers derived from the (meth) acrylic monomers that are obtained by polymerization / crosslinking of the monomer of structures I, II and III with comonomers having two or more polymerizable groups to obtain polymeric materials such as insoluble networks in the form of dense membranes or movies.

Non-limiting examples of comonomers having two or more polymerizable groups are 2-hydroxyethyl acrylate (AEH) or ethylene glycol dimethacrylate (EGDMA).

Specifically, the solid polymeric materials obtained, in the form of dense membranes or films, are characterized by an ideal combination of mechanical properties, both dry and swollen, that is, with water and organic solvents (for example acetone) within the polymer network. This makes them

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Especially advantageous materials for use in the detection of vapors of nitroderivative and explosive compounds such as TNT, RDX and PETN.

The polymeric materials of the invention undergo fluorescence changes, either in the form of damping of this or increasing the emission intensity, in the presence of vapors of explosive nitroderivative compounds (TNT, RDX and PETN), as well as other nitro derivatives, for example l-chloro-4-nitrobenzene (C1NB), 2-nitro-m-xylene (NX), 1,3-dinitrobenzene (1,3— DNB), 2-nitrotoluene (2-NT), 4-nitrotoluene ( 4-NT) and 2,4-dinitrotoluene (2,4-DNT).

The individual use of each material makes it possible to detect the presence of explosive nitroderivative compounds and non-explosive nitrated compounds through the study of the fluorescence spectra of the polymeric materials in the atmospheres of interest, differentiating them by mathematical treatment. Thus, for example, the use of joint data of three materials, in what is commonly referred to in this field as "sensor matrix", allows the selective detection, and therefore the differentiation, of each and every one of the aforementioned compounds, both those considered explosive and non-explosive nitrates. The joint data is analyzed by statistical algorithms.

The following Scheme 1 illustrates an illustrative and non-limiting example of a process for obtaining vinyl monomers I.

Scheme 1

image2

image3

The complexes derived from Tb (III) and Sm (III) are obtained by treatment of I with terbium and samarium nitrate, respectively, and give rise to organometallic compounds with complex stoichiometry such as those shown as an example for compounds II and III.

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image4

Sm (lll)

(in)

Polymers derived from (meth) acrylic monomers that are obtained by polymerization / crosslinking of the monomers of structures I, II and III with comonomers that have two or more groups

both hydrophilic and hydrophobic polymerizable, with one or several polymerizable multiple bonds, allow to obtain the polymeric materials of the invention as insoluble networks in the form of dense membranes or films. The synthesis of the polymers can be carried out by direct reaction of the vinyl bond using a thermal or photochemical radical initiator. In general the polymerization of the 15 monomers or vinyl comonomers can be carried out by any of the procedures described in the literature for the polymerization of multiple bonds.

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According to the second aspect of the

invention, the polymeric materials of the invention thus obtained as insoluble nets in the form of

dense membranes or film are used for the

fluorogenic detection of explosive vapors

nitroderivatives, in the form of sensing membranes

individual or as a matrix of sensing membranes.

Next, the invention is described based on embodiments. The examples are illustrative of the invention and in no case limiting it.

Examples

Example 1. Synthesis of monomers

This example illustrates the preparation and characterization of the monomer N- (4- (bis (4-hydroxy-2-

oxocumarin-3-yl) methyl) phenyl) methacrylamide) (I) and the complexes derived from it with terbium (II) and with samarium (III), which was carried out by the following synthetic route represented in Scheme 1:

image5

image6

Synthesis of 3,3 ’- ((4-nitrophenyl) methylene) bis (4-

hydroxycoumarin-2-one)

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In a round bottom flask, 30.83 mmol (5 g) of 4-hydroxycoumarin are dissolved in 50 ml of absolute ethanol as solvent. Then 15.42 mmol (2.33 g) of 4-nitrobenzaldehyde are added in a 2: 1 molar ratio. The mixture is heated to reflux with stirring until an insoluble yellow precipitate appears. After cooling to room temperature, the product is filtered and washed several times with ethanol, finally drying at 30 ° C, obtaining a yield of 15 75% (characterization, see Fig. 1).

Synthesis of 3,3 ’- ((4-aminophenyl) methylene) bis (4- hydroxycoumarin-2-one)

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In a hydrogenation reactor, 4.37 mmol (2 g) of 3,3 '- ((4-nitrophenyl) methylene) bis (4-hydroxycoumarin-2-one) are added together with 20 ml of ethanol and 0.2 g of Pd / C (10% by weight of Pd). The system is purged and pressurized with hydrogen up to 70 psi. The mixture is stirred at 60 ° C for 6 hours, replacing the hydrogen consumed every 15 minutes until the pressure stabilizes. The resulting crude is filtered and washed with DMA. The solution obtained is added dropwise over distilled water (500 ml) with stirring, obtaining a brown solid, which is finally dried at 40 ° C, obtaining a yield of 80% (characterization: see Fig. 2).

Synthesis of N- (4- (bis (4-hydroxy-2-oxocumarin-3- yl) methyl) phenyl) methacrylamide) (I)

In a round bottom flask, 11.70 mmol (5 g) of 3,3 '- ((4-aminophenyl) methylene) - bis (4-hydroxycoumarin-2-one) are dissolved in 20 ml of NMP using atmosphere of nitrogen. Subsequently, 14.04 mmol (1.37 ml) of methacryloyl chloride, dropwise, and 5% by weight of LiCl are added. The mixture is kept under stirring at room temperature for 4 hours. Finally, the solution is added on distilled water under stirring, obtaining a light brown solid. This solid is washed with water (3x15 ml) and with ether (3x15 ml). The solid is dried under vacuum at 60 ° C overnight, obtaining a yield of 80% (characterization: See Fig. 3).

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Synthesis of complexes II and III derived from N- (4- (bis (4-hydroxy-2-oxo-coumarin-3-yl) methyl) phenyl) -methacrylamide) with terbium (III) and with Samarium (III)

At a solution of N- (4- (bis (4-hydroxy-2- oxocumarin-3-yl) methyl) phenyl) methacrylamide) (0.41 mmol,

200.0 mg) in acetonitrile (20 ml) a solution of the terbium (III) salt (Tb (1103) 3 (0.41 mmol, 178.3 mg) in milliQ water (minimum quantity) is added. it is kept under stirring for 30 minutes, the solution is then basified to pH 4.5-5 by the dropwise addition of a 0.1M NaOH solution, a brown precipitate appearing, this solid is filtered and washed several times with water and acetonitrile, finally drying at 40 ° C, giving a 75% yield (characterization: See Fig. 4).

 He

 monomer sensor using the salt of

 samarium (III)

 Sm (N03) 3 was obtained similarly in

 solid form

 pale pink with a

75% yield (characterization: See Fig. 5).

Example 2: Preparation of sensor membranes

By block polymerization, three membranes were prepared with the composition indicated below.

 Monomers:

 2-hydroxyethyl acrylate (A2HE), and

 I, II and III, in an A2HE relationship: I,

 II, III of 99: 1

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 Crosslinker:

 ethylene glycol dimethacrylate (EGDMA), in a percentage by weight over the rest of the 2% monomers

 Photoinitiator

 2,2-dimethoxy-2-phenylacetophenone in a weight percentage of 1.56%, based on the total weight of the monomers

The resulting solution was injected into a mold between silanized crystals, 100 pm thick, in the absence of oxygen, and placed under irradiation of a mercury UV lamp (250W, Philips HPL-N, emission bands in the UV region at 304, 314, 335 and 366 nm, with maximum emission at 366 nm) (characterization: see Fig. 6). The polymerization of comonomers I, II and III gave rise to the membranes MI, Mil and Mill, respectively.

Example 3: Fluorogenic detection of vapors of nitroderivative and explosive compounds, TNT, RDX and PETN by means of the MI, Mil and Mill sensor membranes

This example illustrates the behavior as fluorogenic sensors of the dense membranes obtained by copolymerization of commercial monomers together with the vinyl monomers obtained in Example 1, towards the presence of vapors of nitroderivative and explosive compounds (TNT, RDX and PETN).

Fluorescence measurements for the detection of vapors of nitroderivative compounds were carried out in accordance with methods described in the literature (Q. Fang, J. Geng., B. Liu, D. Gao, F. Li, Z. Wang, G.

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Guan, Z. Zhang. Chem. Eur. J. 2009, 15, 11507-11514).

For this, solutions of each of the nitroderivative compounds in 0.1M acetonitrile were prepared. Then a milliliter of the solution was added on a piece of gauze between 40-60 mg, allowing to dry at room temperature overnight. The piece of gauze was heated in an open vial at 100 ° C for 10 minutes to remove traces of moisture and then for 1 hour at 100 ° C in a sealed vial. After this time, it was kept at room temperature for 5 minutes and the gauze was quickly introduced together with the dense membrane in a sealed measuring cell. Fluorescence spectra were obtained every 30 seconds or 1 minute at 25 ° C. The excitation wavelength was 360 nm and the opening of the excitation / emission windows was 5/5, 2.5 / 5, and 10/10 nm, for dense membranes MI, Mil and Mill respectively. The fluorescence spectra obtained are shown in Figs. 7, 8 and 9.

The joint analysis of these fluorescence spectra using multivariate data analysis techniques allows selective detection and differentiation of explosive and non-explosive nitro-derived compounds. In addition, applying regression and classification techniques based on latent variables and / or techniques based on neural networks to complete fluorescence spectra, the probabilities of committing false positives and false negatives can be calculated.

Claims (9)

1.- Monomers of structure I and complexes obtained with I by interaction with salts of Tb (III) and Sm (III) with 5 complex stoichiometry as fluorogenic sensors of nitroderivative explosive vapors. image 1 image2 10 2.- Monomers obtained with Sm (III) with fluorogenic of structure I and complexes II and III I by interaction with salts of Tb (III) and complex stoichiometry as vapor sensors of nitroderivative explosives. 5 10 fifteen twenty 25 30 image3 Sm (lll) (III) 3. Monomers of structure I and complexes II and III obtained with I by interaction with salts of Tb (III) and Sm (III) according to claim 1 or 2, characterized in that as salts of Tb (III) and Sm (III) Terbium (III) nitrate and samarium (III) nitrate are used respectively. 4. - Solid polymeric materials derived from (meth) acrylic monomers that are obtained by polymerization of the monomers of structures I, II and III according to claim 1, 2 or 3, with comonomers having two or more polymerizable and crosslinking groups, such as Fluorogenic sensors of nitro-derived explosive vapors. 5. - Solid polymeric materials according to claim 4, characterized in that, as comonomers having two or more polymerizable groups, 2-hydroxyethyl acrylate or dimethacrylate of 5 10 fifteen twenty 25 ethylene glycol 6. - Solid polymeric materials according to claim 4, characterized in that they are in the form of dense membranes. 7. - Use of the solid polymeric materials according to claim 6 in the form of sensor membranes for the detection of vapors of nitro-derived explosives by studying the fluorescence spectra of the polymeric materials in the atmospheres of interest. 8. - Use of solid polymeric materials according to claim 7 in the form of a matrix of sensor membranes for the selective detection and differentiation of explosive and non-explosive nitroderivative compounds by studying the fluorescence spectra of polymeric materials in the atmospheres of interest . 9. - Use of multivariate data analysis techniques, according to claims 7 and 8, for the selective detection and differentiation of explosive and non-explosive nitro-derived compounds with evaluation of the probabilities of committing false positives and false negatives by applying regression and classification techniques. based on latent variables and / or techniques based on neural networks to complete fluorescence spectra.