Complex and use thereof as a sensor for detecting scopolamine

Abstract

The present invention relates to a supramolecular complex comprising a three-dimensional molecular cage and a fluorophore. The invention also relates to the use of the complex, or a composition containing same, as a sensor for detecting and / or quantifying scopolamine in a sample.

Description

[0001] COMPLEX AND ITS USE AS A SENSOR FOR SCOPOLAMINE DETECTION

[0002] The present invention relates to a complex comprising a three-dimensional molecular box and a fluorophore, and further relates to its use as a sensor for the detection and / or quantification of scopolamine in a sample.

[0003] BACKGROUND OF THE INVENTION

[0004] In European countries, up to 20% of women have experienced some form of sexual assault during adulthood, but the lack of adequate monitoring systems means that the full extent of drug-facilitated sexual assault (DFSA) remains unknown. Furthermore, recorded law enforcement reports often fail to differentiate between drug-facilitated sexual assault and sexual assault committed using other forms of force. Therefore, establishing forensic evidence of DFSA is significantly difficult.

[0005] Some of these drugs are, for example, gamma-hydroxybutyrate (GHB or liquid ecstasy), methylenedioxypyrovalerone (MDPV or cannibal drug), ketamine, flunitrazepam and scopolamine (SCP, also known as burundanga).

[0006] These drugs can be detected using various instrumental analytical techniques, such as high-performance liquid chromatography-mass spectrometry (HPLC-MS), gas chromatography-mass spectrometry (GC-MS), and bioanalytical procedures like ELISA immunoassays. In fact, chromatography-mass spectrometry is currently the most widely used technique for detecting these drugs (Li Liu et al., Am. J. Clin. Pathol. 2018, 149, 105-116). However, most of these methods require samples to be sent to qualified laboratories for analysis, necessitating complex and expensive techniques performed by trained personnel.

[0007] For the detection of these drugs in samples, chromogenic or fluorogenic chemical sensors also exist (Chenzing Guo et al., Coord. Chem. Rev. 2020, 427, 213560), based on a molecule that reacts chemically with the analyte of interest (i.e., the drug of abuse to be detected). However, these chemical sensors have problems with specificity and sensitivity, mainly because analytes with similar chemical structures also react and exhibit a response. In addition, these chemical sensors require relatively long measurement times.

[0008] On the other hand, patent document ES2930539A1 describes a nanosensor made of mesoporous silica nanoparticles of the MCM-41 type (MSNs) and rhodamine for the detection of scopolamine (SCP) in saliva samples. The MSNs are functionalized on their surface with a bethanechol derivative (carbamyl-p-methylcholine chloride), which is a non-selective agonist of the muscarinic receptor, specifically acting by increasing the activity of M2-AChR.

[0009] Therefore, there is a need in the state of the art to provide methods or devices capable of detecting such drugs, specifically scopolamine, in different samples, without the need for complex devices or qualified personnel in a simple, fast, efficient way, with high specificity and sensitivity, allowing the detection of this type of substance in situ and at site.

[0010] DESCRIPTION OF THE INVENTION

[0011] The present invention provides the design, preparation, and characterization of a complex for use as a nanosensor for the rapid, selective, and in situ detection of scopolamine. The invention enables the specific and selective quantitative detection of scopolamine by implementing a displacement reaction of a fluorescent compound encapsulated in a molecular box, forming a complex. In this way, the three-dimensional cavity of the molecular box has the capacity to specifically recognize the analyte scopolamine, thereby allowing the release of the fluorogenic indicator previously encapsulated within the box. Monitoring of the signal resulting from the release of the fluorogenic indicator by the developed sensor has shown the ability to detect scopolamine-containing samples in less than 5 minutes with a low detection limit of 59 pg / mL and high specificity for other drugs of abuse.This new system allows the detection of the presence of scopolamine in samples using a fast and selective method.

[0012] In one aspect, the present invention relates to a complex comprising:

[0013] a. a three-dimensional molecular box formed by:

[0014] two divalent metal ions of Pd and four L ligands of formula (I):

[0015]

[0016] coordinated with both metal ions by metal-ligand coordination bonds, and where each represents the bond to each of the metal ions, b. at least one fluorophore compound in its anionic form encapsulated in the molecular box, and

[0017] c. optionally counterions.

[0018] The molecular box forms a quasi-spherical three-dimensional structure and has the following formula C1 ([Cio4H82N240i2Pd2] 2+ ):

[0019]

[0020] In a preferred embodiment of the invention complex, one or two fluorophore compounds are encapsulated in the molecular box or C1.

[0021] In another preferred embodiment of the invention, the anionic fluorophore encapsulated in the three-dimensional molecular box is selected from fluorescein, 2,7-dichlorofluorescein, rhodamine 110, and any other fluorophore of similar molecular size and shape. Preferably, the fluorophore is fluorescein.

[0022] The fluorophore compound is encapsulated in its anionic form to maximize the electrostatic interaction between the Pd box with four positive charges and the negatively charged fluorophore. Preferably, it would be in monoanionic or dianionic form; for example, fluorescein and 2,7-dichlorofluorescein can be encapsulated in either their monoanionic or dianionic form.

[0023]

[0024] and in the case of rhodamine 110 it can be in its monoanionic form:

[0025]

[0026] In a more preferred embodiment, the fluorophore compound is fluorescein in its dianionic form:

[0027]

[0028] and more preferably in the complex two molecules are encapsulated, where the molecular formula of the complex would be [Cio4H82N240i2Pd2][C2oHi20s]2. In this case counterions are not necessary in the complex.

[0029] However, depending on the negative charge of the fluorophore compound(s) in their anionic form, encapsulated in the box, the complex may have one or more counterions. In a preferred embodiment, the counterion(s) is selected from [NOs'] and [BF4], or other anions of similar molecular size. The number of counterions will depend on their own charge and that of the fluorophore compound(s) to ensure the complex is neutral. In a preferred embodiment, the counterion(s) is NO3-; for example, when the complex has a fluorescein molecule in its dianionic form encapsulated in the box and the counterions are NOs', the formula of the complex would be: [Cio4H82N240i2Pd2][C2oHi20s][NO3]2

[0030] Another aspect of the present invention relates to the method of obtaining the complex of the invention, which comprises:

[0031] (i) prepare a solution of the fluorophore compound in a mixture of water / polar organic solvent, and

[0032] (i) add the molecular box to the solution obtained in (i) to form the complex.

[0033] In a preferred embodiment, the method further comprises: (iii) precipitating the complex obtained by (i) adding excess water, to isolate the complex obtained.

[0034] The fluorophore compound in step (i) can be selected from fluorescein, 2,7-dichlorofluorescein, rhodamine 110, and any other fluorophore of similar molecular size and shape. Fluorescein is preferred.

[0035] In a more preferred embodiment, the fluorophore compound is prepared in (i) at a concentration in the range of 2.5 to 175 pM, more preferably 50 pM, in a mixture of water / polar organic solvent, preferably water / DMSO in ratios from 9:1 (v / v) to 1:1 (v / v), and more preferably in a ratio of 8:2 (v / v).

[0036] The molecular box that is added in (i) can be C1 NO3 with the chemical formula:

[0037] [CiO4H82N24Oi2Pd2][NOs]4 in a concentration in the range of 1.25 to 87.5 pM, more preferably 25 pM, to the solution obtained in (i).

[0038] Another aspect of the present invention relates to a composition comprising at least one previously described complex and a mixture of a polar organic solvent and water. The polar organic solvent may be dimethyl sulfoxide (DMSO), N,N-dimethylformamide (DMF), or other polar organic solvents. Preferably, the organic solvent is dimethyl sulfoxide (DMSO), preferably in a water / DMSO ratio from 9:1 (v / v) to 1:1 (v / v), and more preferably in a ratio of 8:2 (v / v).

[0039] In a more preferred embodiment of the composition of the invention, said composition comprises the complex [Cio4H82N240i2Pd2][C2oHi2O5]2, the complex [Cio4H82N240i2Pd2][C2oHi2O5][NO3]2, or any combination thereof. Supramolecular interactions between the functional groups forming the cavity of the molecular box and the fluorescent compound cause it to be encapsulated within the inner cavity of the box. This inner cavity is preferably capable of recognizing an analyte and, thereby, allows the release of the fluorescent indicator previously encapsulated within the box by displacement. The release of the fluorophore allows for obtaining a measurable signal directly proportional to the concentration of analyte present in the sample, making it possible to use the complex of the invention or the composition containing it as a sensor for the detection of analytes.

[0040] Therefore, another aspect of the present invention relates to the use of the previously described complex or composition as a fluorimetric sensor.

[0041] Another aspect of the invention relates to a fluorimetric sensor comprising the previously described complex or composition.

[0042] The encapsulation reaction between the molecular box and fluorescein, forming the complex of the invention, is reversible. Because scopolamine has a greater affinity for the molecular box than fluorescein, the presence of scopolamine allows the release of fluorescein from within the cavity of the molecular box due to a displacement reaction. The release of fluorescein results in an increase in fluorescence. Thus, the complex of the present invention, described above and formed by the three-dimensional molecular box and fluorescein, or the composition or sensor comprising it, is useful for the detection and / or quantification of scopolamine in a sample, demonstrating the ability to detect the presence of scopolamine with high specificity in less than 5 minutes and with a detection limit of 59 ppm compared to other drugs of abuse.With all this, this new system has proven to be a fast, selective and reliable method for the detection of scopolamine in aqueous samples.

[0043] Therefore, another aspect of the present invention relates to the use of the previously described complex, the previously described composition, or the previously described sensor, for the detection and / or quantification of scopolamine in a sample.

[0044] The different affinities of fluorescein and scopolamine for the box cavity result in changes in fluorescence emission intensity. Fluorescein in the fluorescein-box complex has a low fluorescence intensity due to fluorescence quenching mechanisms between the box and the fluorophore. When the fluorescein-box complex is exposed to a solution containing scopolamine, the analyte's affinity for the box leads to its encapsulation, resulting in the release of fluorescein from within the box. This release results in an increase in fluorescence emission intensity. The fluorophore displacement method employed is a robust technique that also allows for high selectivity thanks to the non-covalent interactions between the analyte and the three-dimensional cavity of the box.In this sense, the fluorophore must have a lower affinity for the molecular box than that of the analyte in order for the displacement reaction to take place.

[0045] The advantages of the object of the present invention for the detection and / or quantification of scopolamine are as follows:

[0046] Short test times (less than 5 minutes) and highly sensitive.

[0047] It does not require highly qualified personnel to perform the test or the transfer of the sample to a laboratory.

[0048] Generation of an easily mediated fluorimetric response that does not require sophisticated instrumentation for its identification, requiring only a standard fluorometer.

[0049] - High robustness and sensitivity of the sensor with a low detection limit (59 ppm).

[0050] Simple industrial scaling, since the molecular box can be synthesized on a multi-grain scale allowing the preparation of quantities of fluorescein sensor complex suitable for a large number of analyses.

[0051] - High system stability at room temperature, facilitating its distribution and storage.

[0052] It facilitates decision-making by law enforcement agencies and analytical laboratories. - Real-time analysis compatible with drug-facilitated sexual assault crimes, allowing for on-site measurement without the need to transport the sample to specialized laboratories (for example, measuring the fluorimetric response with a standard portable fluorimeter).

[0053] Another aspect of the present invention relates to a method for detecting and / or quantifying scopolamine in a sample, comprising:

[0054] a. add the sample to the composition described above; and

[0055] b. detect the presence or absence of a detectable signal sensitive to scopolamine emitted by the fluorophore, where the intensity of the detectable signal is indicative of the concentration of scopolamine in the sample.

[0056] Preferably measure fluorescence at a wavelength in the range of 500 nm to 560 nm, preferably at 535 nm, most preferably using a fluorometer. The excitation wavelength is in the range of 460 nm to 480 nm, preferably at 470 nm.

[0057] Another aspect of the present invention relates to a kit for the detection and / or quantification of scopolamine in a sample comprising:

[0058] - at least one previously described complex and

[0059] - a previously described polar organic solvent and water, preferably the organic solvent is DMSO, more preferably in a water / DMSO ratio from 9:1 (v / v) to 1:1 (v / v), and more preferably in a ratio of 8:2 (v / v).

[0060] The term “sample” refers to the composition containing the analyte to be analyzed. In the case of scopolamine, the sample can be a beverage, an aqueous sample containing the drug, or a solid sample of the drug. In each case, the corresponding dilutions must be made, or the solid sample must be dissolved to obtain an aqueous solution.

[0061] Throughout the description and claims, the word "comprises" and its variations are not intended to exclude other technical features, additives, components, or steps. For those skilled in the art, other objects, advantages, and features of the invention will become apparent partly from the description and partly from the practice of the invention. The following examples and figures are provided for illustrative purposes and are not intended to limit the scope of the present invention.

[0062] BRIEF DESCRIPTION OF THE FIGURES

[0063] Fig. 1. Shows the fluorescence spectrum of fluorescein and the molecular inclusion complex C1-F (indicated in the graph as FluoresceinCaja), obtained by fluorescence experiments with a 96 plate reader.

[0064] Fig. 2. Shows the fluorescence spectrum of fluorescein and the C1-F molecular inclusion complex (indicated in the graph as FluoresceinCase), obtained using a spectrofluorometer. Fig. 3. Shows the superposition of 1H (400 MHz) NMR spectra in DMSO-d6 / D2O (1:1) of (a) the free box in the form of an interpenetrating structure or catenane, (b) C1-F inclusion complex, (c) C1 molecular box in the exclusive presence of scopolamine, and (d) C1-F complex in the presence of scopolamine.

[0065] Fig. 4. Shows the superposition of NMR spectra of 1 H (400 MHz) in DMSO-de / D2O (1:1) of (a) the free box in DMSO-de (b) the free box in the form of an interpenetrating structure or catenane, (c) C1-F inclusion complex.

[0066] Fig. 5. Shows the titration of fluorescein (25pM) in H2O / DMSO-de (8:2) against the box (C1) to establish the stoichiometry of inclusion complex formation (C1-F) and association constants.

[0067] Fig. 6. Shows (a) the evaluation of the sensor (C1-F) against scopolamine by means of fluorescence measurements, (b) studies of interferents against different drugs of abuse and (c) semi-logarithmic representation of the fluorescence recovery in the evaluation of C1-F against scopolamine.

[0068] Fig. 7. Shows the controlled release study of the fluorophore from inside the C1-F molecular box in the presence of SCP in triplicate (assay time <5 minutes), (a) Calibration curve: recovery of fluorescence at increasing concentrations of SCP in the sample; (b) calibration line on a semi-logarithmic scale bounded to the limit of linearity.

[0069] EXAMPLES

[0070] The invention will then be illustrated by means of tests carried out by the inventors, which demonstrate the effectiveness of the sensor of the invention.

[0071]

[0072] The synthesis of the molecular box abbreviated as C1 NO3 previously and whose formula is [Cio4H82N240i2Pd2][NC>3]4 is described in the article: Montá-González et al., Chemical science, 2024, Vol. 15, No. 26, pages 10010 - 10017). The preparation of the C1-F complex is represented by scheme 1:

[0073]

[0074] C1-2F

[0075] Scheme 1. Scheme of formation of the C1-F inclusion complex, which is a mixture of the inclusion complexes C1-1F [Cio4H82N240i2Pd2][C2oHi20s][N03]2 and C1-2F [Cio4H82N240i2Pd2][C2oHi20s]2, whose composition depends on the concentration of C1 NO3 and the concentration of fluorescein.

[0076] This preparation was carried out by preparing a 50 pM fluorescein solution in an 8:2 (v / v) water / DMSO mixture. To the aqueous fluorescein solution, 0.5 equivalents of C1NO3 were added, resulting in a final concentration of 25 pM C1-F in solution. This promoted the formation of the C1-F inclusion complex, leading to a final 25 pM C1-F complex. The formation of the C1-F inclusion complex through supramolecular complexing equilibria leads to the simultaneous formation of the C1-1F inclusion complex in a 1:1 ratio (1 part C1 to 1 part fluorescein) and the C1-2F inclusion complex in a 1:2 ratio (1 part C1 to 2 parts fluorescein), depending on the molar ratio of C1 to fluorescein. Therefore, the C1-F inclusion complex is a mixture of the C1-1F and C1-2F inclusion complexes.Under the experimental conditions used of 25 pM C1 NO3 and 50 pM fluorescein, i.e. 2 equivalents of fluorescein with respect to the box, the C1-2F complex is mostly formed.

[0077] The formation of the C1-F inclusion complex was followed through spectrofluorimetry experiments, establishing the emission maximum at 515 nm, with a significant quenching of the signal observed at around 7,000 counts.

[0078] Figure 1 shows the formation of the C1-F inclusion complex and the quenching of the signal associated with the encapsulation of fluorescein inside the cavity, going from an emission intensity of -9,000 counts to -2,000 counts, this being a notable loss of the emission intensity of the fluorescein (measurements made with a 96 plate reader, the intensity results differ from those of a spectrofluorometer due to the greater sensitivity of the latter).

[0079] The characterization of the obtained C1-F inclusion complex was carried out using various techniques. Direct characterization was performed through fluorescence experiments, as previously described. Unequivocal confirmation of inclusion complex formation was obtained by obtaining the spectra of free fluorescein, showing an emission maximum at 515 nm, and of the C1-F inclusion complex, revealing a significant loss of intensity associated with the encapsulation phenomenon within the molecular box cavity (Fig. 1). Measurements performed with a spectrofluorometer show an intensity loss of approximately 88%, decreasing from an emission intensity of -1,400 counts to -150 counts, demonstrating the effective encapsulation of F, i.e., the formation of the C1-F inclusion complex, as observed in the superposition of spectra in Fig. 2.

[0080] Once the formation of the C1-F inclusion complex was confirmed by optical methods, additional proton nuclear magnetic resonance (¹H NMR) experiments were performed, confirming the formation of the C1-F complex. The signals shown in Figures 3 and 4 are a clipping of the complete NMR spectrum, highlighting only the most representative signals, and show shifts in the free box signals verifying fluorescein encapsulation with the formation of the C1-F inclusion complex.

[0081] The C1 NO3 box undergoes catenation, forming an interpenetrating catenane-type structure (Fig. 3a and Fig. 4b) that cleaves in the presence of fluorescein, resulting in the C1-F complex, which does not correspond to the chemical shifts of the free box in DMSO-O6 or in the catenane form. The chemical shifts are detailed in Fig. 4.

[0082] Spectroscopic data C1 NO3 in DMSO-from:

[0083] 1H NMR (400 MHz, DMSO-Ó6) d 7.19 (2H, d, J = 8.8 Hz, H-b and H-b’), 7.82 (1H, dd, J = 8.0, 5.8 Hz, H-i), 7.97 (2H, d, J = 8.8 Hz, H-c and H-c’), 8.33 (1H, d, J = 8.8 Hz, H-j), 8.46 (1H, s, H-k), 9.39 (1H, d, J = 6.5, H-h), 9.77 (1H, m, H-f), 12.29 (1H, s, NH).

[0084] Datos espectroscópicos C1 NO3 en D2O / DMSO-Ó6 (1:1):

[0085] 1H NMR (400 MHz, DMSO-Ó6) d 6,04-6,62 (2H, s, H-b and H-b’), 7,29-7,48 (2H, s, H-c and H-c’), 7,85 (1H, s, H-i), 8,15 (1H, s, H-j), 8,35 (1H, s, H-k), 9,14 (1H, s, H-h), 10,31-10,07 (1H, s, H-f).

[0086] Datos espectroscópicos C1-F en D2O / DMSO-Ó6 (1:1):

[0087] 1H NMR (400 MHz, DMSO-Ó6) d 6,53-6,69 (2H, s, H-b and H-b’), 7,09 (2H, s, H-c and H-c’), 7,85 (1H, s, H-i), 8,20 (1H, s, H-j), 8,32 (1H, s, H-k), 9,14 (1H, s, H-h), 9,79 (1H, s, H-f).

[0088] Furthermore, a fluorescein solution (Fig. 5) was titrated in a 25 pM H₂O / DMSO₄ mixture (8:2) with increasing concentrations of C₁NO₃ to calculate the ratio of fluorescein molecules encapsulated within the box. From the resulting graph, a fluorescein-to-box ratio of 2:1 was established using standard models of supramolecular complex formation (Pali Thordarson, Chemical Society Reviews, 2011, Vol. 40, pp. 1305–1323), with an affinity constant KHF = (1.9 ± 0.3) × 10 6 M' 1 for the formation of the fluorescein-box complex 1:1 and KHF2 = (4.5 ± 0.7)X10 5 M' 1 for the formation of the fluorescein-box 1:2 complex, thus demonstrating that two molecules of F were encapsulated for each molecule of C1 NO3.

[0089] Example 2. Fluorescein displacement assay in the presence of scopolamine

[0090] An indicator displacement analysis (IDA) was performed using the C1-F complex as a probe in the presence of various drugs. A solution of the C1-F complex obtained in Example 1 (25 pM) in an H₂O / DMSO mixture (80:20 v / v) was evaluated against different drugs (500 pM), including MDMA (3,4-methylenedioxymethamphetamine), cocaine, GBL (gamma-butyrolactone), ketamine, and scopolamine. Fluorescence recovery was measured by spectrofluorimetry (Fig. 6b). The assay time was less than 5 minutes. The greatest increase in fluorescence was observed with scopolamine, reaching 80% recovery, highlighting the good selectivity of the sensor of the invention for scopolamine compared to the other drugs evaluated.

[0091] The affinity of the C1 NO3 molecular box for fluorescein and scopolamine was calculated using the spectrofluorometric titrations described in Figures 5 and 6, yielding the following results:

[0092] Table 1. Association constants obtained from the CTNO3 molecular box by fluorescein and by scopolamine.

[0093]

[0094] The analyte's affinity for the cavity of the box leads to its encapsulation, causing displacement and, consequently, the release of fluorescein from inside the box. This release results in an increase in fluorescence.

[0095] It is concluded that the addition of increasing concentrations of scopolamine (SCP) allows the release of fluorescein, resulting in a measurable signal directly proportional to the concentration of SCP present in the solution. Figure 6 shows a schematic of the release of fluorescein (F) by scopolamine (SCP), where it can be observed that the presence of SCP promotes the displacement of fluorescein from the interior of the molecular box, releasing it and thereby releasing a high intensity of fluorescence emission, leading to the formation of a new complex (C1-SCP).

[0096]

[0097] Low Emission Intensity Scopolamine-C1 Complex

[0098]

[0099] of fluorescence

[0100] Fluorescein released High intensity of fluorescence emission Scheme 1. Schematic representation of the mechanism of fluorophore release from the interior of the molecular box in the presence of SCP producing an increase in the intensity of fluorescence emission.

[0101] Additionally, to calculate the different analytical parameters, a titration was performed in which increasing amounts of scopolamine up to 200 equivalents (0-5,000 pM) were added to a 25 pM solution of the C1-F complex (obtained by reacting 25 pM CTNO3 and 50 pM fluorescein) in an H2O / DMSO mixture (80:20 v / v). Fluorescence recovery was observed due to the release of fluorescein (Figures 6a and 6c). Using these data, a calibration curve was obtained (Figure 7b) from which the different analytical parameters were calculated. The calculated analytical parameters were the limit of detection (LOD), limit of quantification (LOQ), limit of linearity (LOL), and useful range (UR) of the detection system against different concentrations of SCP.

[0102] A plot of fluorescence against scopolamine concentration was performed, resulting in a curve (Fig. 7a), and a plot of normalized fluorescence against the logarithm of the scopolamine concentration resulted in a straight line (Fig. 7b). Based on the plot in Fig. 7b, a calibration curve was obtained that allows for the quantification of SCP over a wide range, making this supramolecular detection system the first described to date for the in situ and at-site detection of scopolamine in aqueous media. Thanks to the controlled release of fluorescein, this sensor demonstrated good LDD (59 ppm) and LDQ (138 ppm), which are summarized below, along with other analytical parameters, in Table 2.

[0103] Table 2. Analytical parameters obtained from the calibration curve (n=4) by titration of the C1-F complex (25 pM solution of the C1-F complex obtained by reaction between 25 pM CTNO3 box and 50 pM fluorescein) against an aqueous solution of free SCP with an assay time <5 minutes. Values ​​obtained from the mean of 4 independent replicates.

[0104]

Claims

CLAIMS 1. A complex comprising: a. a three-dimensional molecular box formed by: two divalent metal ions of Pd and four L ligands of formula (I): coordinated with both metal ions through metal-ligand coordination bonds, and where each represents the bond to each of the metal ions, b. at least one fluorophore compound in its anionic form encapsulated in the molecular box, and c. optionally counterions.

2. The complex according to claim 1, wherein one or two fluorophore compounds are encapsulated in the molecular box.

3. The complex according to any of claims 1 or 2, wherein the fluorophore compounds are monoanionic or dianionic.

4. The complex according to any of claims 1 to 3, wherein the fluorophore compound is selected from fluorescein, 2,7-dichlorofluorescein and rhodamine 110.

5. The complex according to any of claims 1 to 4, wherein the counterions are [NO3] or [BF4-].

6. A method for obtaining the complex described in any of claims 1 to 5, comprising (i) prepare a solution of a fluorophore compound in a mixture of water / polar organic solvent, and (i) add the molecular box to the solution obtained in (i).

7. The method according to claim 6, further comprising: (iii) precipitate the complex obtained in (i) by adding excess water.

8. Composition comprising at least one complex described according to any of claims 1 to 5 and a polar organic solvent and water.

9. Composition according to claim 8, wherein the complex is selected from the complex [Cio4H82N240i2Pd2][C2oHi205]2, the complex [Cio4H82N240i2Pd2][C2oHi20s][N03]2 or any combination of both.

10. Composition according to any of claims 8 or 9, wherein the polar organic solvent is dimethyl sulfoxide (DMSO) or N,N-dimethylformamide (DMF).

11. Use of the complex described according to any of claims 1 to 5 or of the composition described according to any of claims 8 to 10, as a fluometric sensor.

12. Fluometric sensor comprising the complex described according to any of claims 1 to 5 or the composition described according to any of claims 8 to 10.

13. Use of the complex described according to claims 1 or 5 or of the composition described according to any of claims 8 to 10 or the fluorometric sensor described according to claim 11, for the detection and / or quantification of scopolamine in a sample.

14. Method for detecting and / or quantifying scopolamine in a sample comprising: a. add the sample to the composition described according to any of claims 8 to 10; and b. detect the presence or absence of a detectable signal sensitive to scopolamine emitted by the fluorophore, where the intensity of the detectable signal is indicative of the concentration of scopolamine in the sample.

15. Kit for the detection and / or quantification of scopolamine in a sample comprising: - at least one complex described according to claims 1 to 5 and - a polar organic solvent and water.

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