A 1,8-naphthalene imide derivative and its preparation method and use as Hg 2+ Applications of Colorimetric Probes and Fluorescence Switches

Abstract

The present invention discloses a 1,8-naphthalimide derivative and a preparation method thereof and a method for preparing the same as Hg 2+ The application of colorimetric probes and fluorescent switches, the BBN compound reacts with 2-aminothiazole to obtain a 1,8-naphthalene imide derivative. The present invention designs and synthesizes a new 1,8-naphthalene imide derivative (BBNS) with an aminothiazole structure at the 4-position. BBNS can identify Hg in multiple channels 2+ :Can detect Hg in solution colorimetrically 2+ , and can also be made into a test paper-type portable sensor to identify Hg with the naked eye 2+ , and can also be used as an ultrasensitive Hg with a response range of up to picomolar levels 2+ Fluorescent switch.

Description

Technical Field

[0001] The present invention belongs to new material technology, and specifically relates to a 1,8-naphthaleneimide type Hg 2+ Colorimetric probes and fluorescent switches and methods for preparing the same. Background Art

[0002] Hg 2+ It is a toxic heavy metal ion that has attracted much attention. It can detect Hg sensitively and accurately. 2+ It is of vital importance to the environment and human health. Fluorescent probes are widely used in heavy metal ion detection due to their good selectivity, high sensitivity, simple operation, and real-time in-situ use. 1,8-Naphthalimide derivatives are an important class of heavy metal ion fluorescent probes, among which Hg 2+ The research on fluorescent probes is very active. The prior art reports a disulfide-linked 1,8-naphthalimide dimer fluorescent probe for Hg 2+ The detection range is 0-150 μM, and the detection limit is 0.38 μM. The prior art reports a 1,8-naphthaleneimide fluorescent probe with a semicarbazide group at the C-4 position of the naphthalene ring. The probe is sensitive to Hg 2+ The detection range is 18-40 μM, and the detection limit is 0.138 μM. The prior art reports a photo-crosslinked solid fluorescent sensing film containing 1,8-naphthaleneimide for Hg in aqueous solution. 2+ Detection of Hg 2+ The detection range is 0-400 μM, and the detection limit is 2.5 μM. The prior art reports a 1,8-naphthalimide ratiometric fluorescent probe for Hg in acetonitrile / water (1:1, v / v, pH=7.0, HEPES buffer). 2+ The detection range is 0-100 μM, and the detection limit is 17.4 nM. The prior art reports a Schiff base type 1,8-naphthalene imide Hg 2+ Fluorescent probe for Hg 2+ The detection range is 50-400 nM, and the detection limit is 0.16 μM.

[0003] Existing 1,8-naphthalene imide Hg 2+ Fluorescent probes are mostly used to detect Hg in solution. 2+ , few can be made into portable sensors; existing probes for Hg 2+ The response range of the probe is generally between micromolar and nanomolar, and the fluorescence performance of the probe increases with the increase of Hg 2+ The concentration increases gradually over a wide range. 2+ Concentration range, fluorescence performance with Hg 2+ The concentration change is abrupt, and the response concentration reaches the picomolar level of 1,8-naphthalimide Hg 2+No reports on fluorescent switches have been reported. Summary of the invention

[0004] The present invention synthesizes a novel multi-channel Hg 2+ Colorimetric and fluorescent probe, which can detect Hg in solution colorimetrically 2+ , and can also be made into a test paper-type portable sensor to identify Hg with the naked eye 2+ , and can also be used as an ultrasensitive Hg 2+ Fluorescent switch.

[0005] The present invention adopts the following technical solution:

[0006] A 1,8-naphthaleneimide derivative, the chemical structure of which is as follows:

[0007]

[0008] The present invention discloses a method for preparing the above-mentioned 1,8-naphthalimide derivatives, wherein a BBN compound is reacted with 2-aminothiazole to obtain a 1,8-naphthalimide derivative. Preferably, the reaction is carried out in the presence of a noble metal catalyst, an inorganic base, an organic ligand, and a solvent. Further preferably, the noble metal catalyst includes a palladium catalyst, preferably an inorganic palladium catalyst; the inorganic base includes a cesium salt, a potassium salt, a sodium salt, etc., preferably a carbonate; the organic ligand includes a phosphine ligand, preferably containing phenylphosphine; and the solvent is an organic solvent, such as DMF.

[0009] In the present invention, the reaction is carried out under an inert gas, such as nitrogen, at a reaction temperature of 100 to 150° C., preferably 110 to 130° C., and for a reaction time of 1 to 5 hours, preferably 2 to 4 hours.

[0010] In the present invention, the molar ratio of the BBN compound, 2-aminothiazole, the noble metal catalyst, the inorganic base and the organic ligand is 1:(1-2):(0.1-0.3):(1-2):(0.3-0.65).

[0011] The present invention discloses the above 1,8-naphthalene imide derivative as or in the preparation of Hg 2+ The use of colorimetric probes, preferably in solution as Hg 2+ Applications of colorimetric probes.

[0012] The present invention discloses the above 1,8-naphthalene imide derivative as or in the preparation of Hg 2+ Application of fluorescent switch.

[0013] The present invention discloses a Hg 2+The detection sensor comprises the above-mentioned 1,8-naphthalene imide derivative and a substrate; the above-mentioned 1,8-naphthalene imide derivative is adsorbed on the substrate. The substrate is a conventional product, such as filter paper, etc.; the specific adsorption operation (method) is a conventional technology.

[0014] The invention discloses a method for detecting Hg in liquid 2+ The method comprises the following steps: mixing the above-mentioned 1,8-naphthalimide derivative with a detection liquid, according to A 525 / A 435 The value of Hg in liquid is detected 2+ Qualitative and quantitative analysis; or mix the above 1,8-naphthaleneimide derivative with the detection liquid and detect Hg in the liquid according to the fluorescence intensity at 550 nm 2+ Qualitative and quantitative analysis; or drop the test liquid on the sensor containing the above-mentioned 1,8-naphthalimide derivatives, and detect Hg in the liquid according to the color change of the sensor 2+ Qualitative and quantitative analysis.

[0015] Positive effects and advantages compared with existing technologies:

[0016] (1) The present invention designs and synthesizes a novel 1,8-naphthalimide derivative with a yield higher than that of similar products in the literature;

[0017] (2) A probe with multi-channel detection of Hg was realized 2+ (It can detect Hg in solution by colorimetry 2+ , and can be made into a portable sensor to identify Hg 2+ , can also be used as Hg 2+ Fluorescent switch);

[0018] (3) It can be made into a test paper-type portable sensor to identify Hg with the naked eye 2+ ;;

[0019] (4) As Hg 2+ The fluorescence switch can reach the picomolar level of ultrasensitive response to Hg 2+ ;

[0020] (5) The detection and identification process has good selectivity, sensitivity and strong anti-interference ability;

[0021] (6) Hg 2+ The response process is fast and reversible. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] Figure 1 The diagram is a schematic diagram of the synthesis of the 1,8-naphthalene imide derivative BBNS of the present invention, the chemical structural formula of the BBN compound, and a schematic diagram of the chemical structural formula of BBNS.

[0023] Figure 2 is the UV-visible absorption spectrum of BBNS before and after adding 17 metal ions, where a is the absorption spectrum and b is the ratio of the absorbance of BBNS solution at 525 nm and 435 nm; solvent: DMSO / H2O (10 / 90, v / v); concentration: BBNS is 10 μM, metal ions are 100 μM.

[0024] Figure 3 Hg 2+ UV-visible absorption spectra of BBNS at concentrations of 0-100 μM (a), the ratio of the absorbance of BBNS at 525 nm to that at 435 nm (A) 525 / A 435 With Hg 2+ Linear relationship diagram between concentrations of 0, 1, 3, 5, 7, 9, 10, 11, 13, 15, 17, 19, and 20 μM (b); solvent: DMSO / H2O (10 / 90, v / v); concentration: BBNS is 10 μM.

[0025] Figure 4 For coexisting metal ions BBNS-Hg 2+ The ratio of the maximum absorbance at 525 nm to that at 435 nm in DMSO / H2O (10 / 90, v / v) is A 525 / A 435 Effects of BBNS on the performance of the PD-123R-treated mice; concentrations: 10 μM for BBNS and 20 μM for various metal ions.

[0026] Figure 5 BBNS-Hg 2+ The ratio of the absorbance at 525 nm to that at 435 nm in DMSO / H2O (10 / 90, v / v) is A 525 / A 435 Time response of; concentration: BBNS is 10 μM, Hg 2+ is 20 μM.

[0027] Figure 6 To indicate Hg with BBNS test paper 2+ Concentration photos; BBNS concentrations are 0.265, 2.65, 13.25 mg / g, from left to right Hg 2+ The concentrations are 0, 1, 10, 100, 1000 μM.

[0028] Figure 7Figure 2 is the fluorescence emission spectra of BBNS solution before and after adding 17 metal ions; solvent: DMF / H2O (1 / 99, v / v); concentration: BBNS is 10 μM, metal ions are 100 μM; excitation wavelength: 435 nm, slit width: 10 nm.

[0029] Figure 8 Containing different concentrations of Hg 2+ Fluorescence emission spectra of BBNS solution (a) and the fluorescence intensity at 550 nm and Hg 2+ Solvent: DMF / H2O (1 / 99, v / v), concentration: BBNS is 10 μM, from top to bottom, Hg 2+ Concentrations are 0, 100, 300, 500, 700, 900, 1000, 3000, 7000 pM (blue dots), 10, 30, 50, 70, 90 nM (green dots), 100, 150, 200, 250, 300 nM (red dots), 400, 500, 600 nM (black dots); excitation wavelength: 435 nm, emission wavelength: 550 nm, slit width: 10 nm.

[0030] Fig. 9 For coexisting metal ions BBNS-Hg 2+ Effect of the maximum fluorescence intensity at 550 nm in DMF / H2O (1 / 99, v / v); concentration: 10 μM BBNS, 7000 pM of various metal ions; excitation wavelength: 435 nm, slit width: 10 nm.

[0031] Fig.10 BBNS-Hg 2+ Fluorescence switching cyclability test at 550 nm in DMF / H2O (1 / 99, v / v); concentrations: BBNS 10 μM, Hg 2+ The excitation wavelength is 435 nm and the slit width is 10 nm. DETAILED DESCRIPTION

[0032] The prior art reports a 1,8-naphthaleneimide derivative whose imide site is modified with a pyridine group, but the compound is Ag + Probe, for Hg 2+ The response is very low and cannot be used as Hg 2+ Probe. The present invention designs and synthesizes a novel 1,8-naphthaleneimide derivative (BBNS) with an aminothiazole structure at the 4-position. BBNS can recognize Hg through multiple channels. 2+ :Can detect Hg in solution colorimetrically 2+ , and can also be made into a test paper-type portable sensor to identify Hg with the naked eye2+ , and can also be used as an ultrasensitive Hg with a response range of up to picomolar levels 2+ Fluorescence switch. The synthesis method is as follows:

[0033] Synthesis of intermediate BBN: Dissolve 4-bromo-1,8-naphthalene anhydride in anhydrous ethanol, heat to 40-60 °C with stirring under N2 protection, add n-butylamine, reflux for 15-30 hours, stop the reaction, cool to room temperature, pour into ice water, a dark yellow precipitate is precipitated, filter, wash the filter cake with deionized water, dry and recrystallize with anhydrous ethanol to obtain a light yellow crystalline solid.

[0034] Synthesis of 1,8-naphthalimide derivative BBNS: Mix BBN (80 mg, 0.24 mmol), cesium carbonate (78~156 mg, 0.24~0.48 mmol), bis(triphenylphosphine)palladium(II) dichloride PdCl2(PPh3)2 (25~50 mg, 0.036~0.072 mmol) and triphenylphosphine PPh3 (20~39 mg, 0.075~0.15 mmol), heat, and add 2-aminothiazole (24~48 mg, 0.24~0.48 mmol) dissolved in DMF with a dropping funnel at a dropping speed of 4~6 drops per minute. After the addition is completed, the temperature is raised to 100~120 ℃, the reaction is reacted for 1~3 h, and the reaction mixture is cooled to room temperature; the heating rate is 10-15 ℃ / min, and the final reaction temperature is 100~120 ℃. Two methods were used for post-treatment: (1) 10 mL of deionized water was added and mixed evenly, and the mixture was extracted with dichloromethane (3×10~3×20 mL), the lower layer solution was collected, and the solvent was removed by rotary evaporation. The residue was purified by silica gel column with petroleum ether / ethyl acetate (5 / 1, v / v) as eluent. (2) The reaction solution was transferred to a centrifuge tube for centrifugation, the upper clear liquid was removed by rotary evaporation, and the residue was purified by silica gel column with petroleum ether / ethyl acetate (5 / 1, v / v) as eluent. Finally, 9.4-36.0 mg of brown-yellow solid (BBNS) was obtained with a yield of 11.1-42.9%.

[0035] The raw materials involved in the present invention are all existing products, and the specific preparation operations and performance tests are conventional technologies. Figure 1 The diagram is a schematic diagram of the synthesis of the 1,8-naphthaleneimide derivative BBNS of the present invention, the chemical structural formula of BBN, and the schematic diagram of the chemical structural formula of BBNS.

[0036] The compound for preparing mercury ions is HgCl2 (AR, Sinopharm Chemical Reagent Co., Ltd.), and the compounds for preparing other metal ions are AlCl3·6H2O, FeCl2·7H2O, MgCl2·6H2O, CrCl3·6H2O, CuSO4·5H2O, Pb(CH3COO)2·3H2O, CdCl2·5H2O, Ni(CH3COO)2·4H2O, anhydrous FeCl3, MnSO4·H2O, CoCl2·6H2O, CaCl2, KCl, AgNO3, ZnCl2, and NaCl (AR, Sinopharm Chemical Reagent Co., Ltd.).

[0037] The present invention adopts conventional methods to mix the metal compound with the solution system.

[0038] Example 1 Preparation of intermediate (BBN)

[0039] Synthesis of intermediate BBN: 4-bromo-1,8-naphthalene anhydride (1.0 g, 3.61 mmol) was dissolved in anhydrous ethanol (15 mL) at room temperature. Under N2 protection, the mixture was heated to 50 °C with stirring. n-butylamine (0.75 mL, 10.25 mmol) was added. The reaction was stopped after reflux for 24 h. The mixture was cooled to room temperature and poured into 30 mL of ice water. A dark yellow precipitate was precipitated. The filter cake was washed twice with deionized water, dried and recrystallized with anhydrous ethanol to obtain 0.75 g of a light yellow crystalline solid with a yield of 62.6%.

[0040] Example 2 Preparation of 1,8-naphthaleneimide derivative (BBNS)

[0041] BBN (80 mg, 0.24 mmol) was dissolved in DMF (3 mL). Cesium carbonate (156 mg, 0.48 mmol), PdCl2(PPh3)2 (50 mg, 0.072 mmol) and PPh3 (39 mg, 0.15 mmol) were added under N2 protection. Heating was started, and 2-aminothiazole (24 mg, 0.24 mmol) dissolved in 5 mL DMF was added dropwise with a dropping funnel at a rate of 4-6 drops per minute. After the addition was completed, the reaction was carried out at 120°C for 3 h. The reaction solution was cooled to room temperature, and then 10 mL of deionized water was added and mixed evenly. The mixture was extracted with dichloromethane (3×10 mL), the lower layer solution was collected, and the solvent was removed by rotary evaporation. The residue was purified by silica gel column with petroleum ether / ethyl acetate (5 / 1, v / v) as eluent to obtain 13 mg of brown-yellow solid (BBNS) with a yield of 15.5%. 1 H NMR (400 MHz, DMSO- d6, δ / ppm): 10.81(s,1H), 8.88(d, J=8.47 Hz, 1H), 8.80(d, J=8.13 Hz, 1H), 8.50(d, J=6.99 Hz, 1H), 8.43(d, J=8.59 Hz, 1H), 7.84(t, J=7.67 Hz, 1H), 7.48(d, J=3.09 Hz, 1H), 7.22(d, J=2.29 Hz, 1H), 4.02(t, J=7.44 Hz, 2H), 1.60(m, J=7.79 Hz, 2H), 1.33(m, J=6.99 Hz, 2H), 0.92(t, J=7.33Hz, 3H). LC-MS m / z calcd. For C 19 H 17 N3O2S: 352.14 [M+H] + , found: 352.30. FT-IR: 1087.17(CSC), 1237.27(CN), 1364.17, 1388.91, 1515.40, 1566.98(ArH), 1 641.30(C=O), 1692.41(C=N), 2868.05, 2921.73, 2946.84(CH3,CH2), 3296.47(NH).

[0042] Example 3 Preparation of 1,8-naphthaleneimide derivative (BBNS)

[0043] BBN (80 mg, 0.24 mmol) was dissolved in DMF (3 mL). Cesium carbonate (78 mg, 0.24 mmol), PdCl2(PPh3)2 (25 mg, 0.036 mmol) and PPh3 (20 mg, 0.075 mmol) were added under N2 protection. Heating was started, and 2-aminothiazole (24 mg, 0.24 mmol) dissolved in 5 mL DMF was added dropwise with a dropping funnel at a rate of 4-6 drops per minute. After the addition was completed, the reaction was carried out at 120 °C for 3 h. The reaction solution was cooled to room temperature, and then 10 mL of deionized water was added and mixed evenly. The mixture was extracted with dichloromethane (3×10 mL), the lower layer solution was collected, and the solvent was removed by rotary evaporation. The residue was purified by silica gel column with petroleum ether / ethyl acetate (5 / 1, v / v) as eluent to obtain 9.4 mg of brown-yellow solid (BBNS) with a yield of 11.1%.

[0044] Example 4 Preparation of 1,8-naphthaleneimide derivative (BBNS)

[0045] BBN (80 mg, 0.24 mmol) was dissolved in DMF (3 mL). Cesium carbonate (156 mg, 0.48 mmol), PdCl2(PPh3)2 (50 mg, 0.072 mmol) and PPh3 (39 mg, 0.15 mmol) were added under N2 protection. Heating was started and 2-aminothiazole (24 mg, 0.24 mmol) dissolved in 5 mL DMF was added dropwise using a dropping funnel at a rate of 4 to 6 drops per minute. After the addition was completed, the mixture was reacted at 100 °C for 1 h, and then 2-aminothiazole (15 mg, 0.15 mmol) was added dropwise and the reaction was continued for 1 h. The reaction solution was cooled to room temperature, and then 10 mL of deionized water was added and mixed evenly. The mixed solution was extracted with dichloromethane (3×20 mL), the lower layer solution was collected, and the solvent was removed by rotary evaporation. The residue was purified by silica gel column with petroleum ether / ethyl acetate (5 / 1, v / v) as eluent to obtain 15.3 mg of brown-yellow solid (BBNS) with a yield of 18.2%.

[0046] Example 5 Preparation of 1,8-naphthaleneimide derivative (BBNS)

[0047] BBN (80 mg, 0.24 mmol) was dissolved in DMF (3 mL), and cesium carbonate (156 mg, 0.48 mmol), PdCl2(PPh3)2 (50 mg, 0.072 mmol) and PPh3 (39 mg, 0.15 mmol) were added under N2 protection. Heating was started, and 2-aminothiazole (48 mg, 0.48 mmol) dissolved in 5 mL DMF was added dropwise with a dropping funnel at a rate of 4-6 drops per minute. After the addition was completed, the reaction was carried out at 120 °C for 3 h. The reaction solution was cooled to room temperature, and then 10 mL of deionized water was added and mixed evenly. The mixture was extracted with dichloromethane (3×20 mL), the lower layer solution was collected, and the solvent was removed by rotary evaporation. The residue was purified by silica gel column with petroleum ether / ethyl acetate (5 / 1, v / v) as eluent to obtain 25.7 mg of brown-yellow solid (BBNS) with a yield of 30.5%.

[0048] Example 6 Preparation of 1,8-naphthaleneimide derivative (BBNS)

[0049] BBN (80 mg, 0.24 mmol) was dissolved in DMF (3 mL). Cesium carbonate (156 mg, 0.48 mmol), PdCl2(PPh3)2 (50 mg, 0.072 mmol) and PPh3 (39 mg, 0.15 mmol) were added under N2 protection. Heating was started, and 2-aminothiazole (48 mg, 0.48 mmol) dissolved in 5 mL DMF was added dropwise with a dropping funnel at a rate of 4-6 drops per minute. After the addition was completed, the reaction was carried out at 120 °C for 3 h. The reaction solution was cooled to room temperature and then transferred to a centrifuge tube for centrifugation. The supernatant was removed by rotary evaporation to remove the solvent. The residue was purified by silica gel column with petroleum ether / ethyl acetate (5 / 1, v / v) as the eluent to obtain 36.0 mg of brown-yellow solid (BBNS) with a yield of 42.9%.

[0050] Example 7 Selectivity of BBNS for Metal Ions in DMSO / H2O (10 / 90, v / v) System

[0051] like Figure 2 As shown in a, in DMSO / H2O (10 / 90, v / v), Hg 2+ The absorbance of BBNS solution at 435 nm was significantly reduced, and the absorption at 525 nm was enhanced. Other metal ions had little effect on the absorption spectrum of BBNS. Calculate the absorbance ratio A of 17 metal ions at 525 nm and 435 nm 525 / A 435 , and plot it with the metal ions as the horizontal axis ( Figure 2 b), visible Hg 2+ Make A 525 / A 435 The other metal ions have increased by 33.6 times. 525 / A 435 The effect was not significant. This indicates that BBNS has a significant effect on Hg 2+ Significant response, possibly as a ratiometric Hg 2+ Colorimetric probes.

[0052] Example 8 Absorbance of BBNS in DMSO / H2O (10 / 90, v / v) system and Hg 2+ The relationship between concentration

[0053] The UV-visible absorption spectra of DMSO / H2O (10 / 90, v / v) solution of BBNS were further investigated along with the Hg 2+ The relationship between the concentrations. Figure 3 As shown in a, with the increase of Hg 2+With the continuous addition of Hg, the absorbance of BBNS solution at 435 nm gradually decreased, and the absorbance at 525 nm gradually increased. 2+ When the concentration increases to 20 μM, the ratio of the absorbance at 525 nm to that at 435 nm is A 525 / A 435 Basically stable. Figure 3 As shown in b, in Hg 2+ In the concentration range (0-20 μM), A 525 / A 435 With Hg 2+ The concentration shows a good linear relationship, and the linear equation is A 525 / A 435 =0.0252×[Hg 2+ ]+0.0157, correlation coefficient R 2 The detection limit was 0.28 μM.

[0054] Example 9 Colorimetric Detection of Hg by Coexisting Metal Ions in DMSO / H2O (10 / 90, v / v) System with BBNS 2+ Impact

[0055] In order to investigate the effect of other coexisting metal ions on the detection of Hg in BBNS 2+ The interference condition of Hg 2+ Ag was added to the BBNS solution + 、Al 3+ , Ca 2+ 、Cd 2+ 、Co 2+ Cr 3+ , Cu 2+ , Fe 2+ , Fe 3+ , K + Mg 2+ , Mn 2+ 、Na + 、Ni 2+ , Pb 2+ 、Zn 2+ The UV-visible absorption spectra of the solution before and after the addition of ions were compared, with the ratio of the absorbance at 525 nm to that at 435 nm, A 525 / A 435 Plotting metal ions, such as Figure 4 As shown, after adding coexisting metal ions, the A 525 / A 435 There is no obvious change, indicating that BBNS detects Hg 2+ It has good resistance to metal ion interference.

[0056] Example 10 Detection of Hg by BBNS in DMSO / H2O (10 / 90, v / v) system 2+ Time responsiveness

[0057] Then, the detection of Hg by BBNS in DMSO / H2O (10 / 90, v / v) system was studied. 2+ The time responsiveness of Figure 5 As shown, A 525 / A 435 It quickly rose to a maximum value within 3 minutes and basically stabilized near the maximum value after 9 minutes. This shows that BBNS has the ability to quickly detect Hg in the DMSO / H2O (10 / 90, v / v) system. 2+ function.

[0058] Example 11 BBNS as a colorimetric probe for detecting Hg 2+ Practicality

[0059] In order to investigate the practicality of BBNS, the pond water and tap water of the Dushu Lake Campus of Soochow University were spiked with BBNS for analysis. The results are shown in Table 1. 2+ Concentration and added Hg 2+ Concentrations are close to Hg 2+ The recovery rate was between 101.7% and 109.6%, and the relative standard deviation of three parallel experiments was less than 4.5%. Therefore, BBNS can effectively detect Hg in actual environmental water samples. 2+ , with good practicality.

[0060]

[0061] Solvent system: DMSO / H2O (10 / 90, v / v), BBNS concentration: 10 μM, RSD: relative standard deviation; for the detection method, see Example 12.

[0062] Example 12 BBNS as a colorimetric probe for detecting Hg 2+ Methods

[0063] Hg 2+ The water sample to be tested is added to the DMSO solution of BBNS, and the volume is fixed with DMSO and H2O so that the volume ratio of DMSO / H2O is 10 / 90, and the concentration of BBNS is 10 μM to obtain the test solution; the UV-visible absorption spectrum of the test solution is measured and A is found. 525 and A 435 , calculate A 525 / A 435 , according to the linear equation A 525 / A 435 =0.0252×[Hg 2+]+0.0157 to calculate the Hg in the sample to be tested 2+ concentration.

[0064] Example 13 Preparation method of BBNS test paper

[0065] Dissolve 3.53 mg and 8.83 mg of BBNS samples in 10 mL and 5 mL of ethanol, respectively, to obtain stock solutions with concentrations of 1 mM and 5 mM, respectively. Then draw 1 mL of BBNS stock solution (1 mM) into a 10 mL volume and dilute it 10 times with ethanol to prepare a 0.1 mM stock solution. Cut conventional filter paper into circular pieces with a diameter of 0.6 cm. Add 20 µL of a stock solution with a concentration of 0.1 (1 or 5) mM on the paper as needed, let it stand at room temperature for 30 min, and then put it in a vacuum drying oven to dry for 5 min to obtain a BBNS test paper that can be used for detection. Put it on a porcelain drip tray for later use. The concentration of BBNS on the test paper is expressed as mass fraction: milligrams (mg) of BNAS adsorbed on each gram (g) of filter paper, which is 0.265 (2.65 or 13.25) mg / g. (The average weight of the filter paper is 0.002 g).

[0066] Example 14 BBNS Test Paper as a Portable Sensor to Indicate Hg 2+

[0067] In order to explore whether BBNS is portable, BBNS was adsorbed on filter paper to make test paper for detecting Hg 2+ . Add different concentrations of Hg to the BBNS test paper. 2+ DMSO / H2O (10 / 90, v / v) solution, the color of the test paper can be observed to change immediately under natural light, and the photographic results are as follows Figure 6 As shown. 2+ As the concentration increases, the color of the test papers with BBNS concentrations of 0.265 mg / g, 2.65 mg / g, and 13.25 mg / g gradually changes from yellow to orange. Therefore, the three concentrations of BBNS test papers can effectively indicate Hg by observing the color change with the naked eye. 2+ .

[0068] Example 15 Selectivity of BBNS fluorescence to metal ions in DMF / H2O (1 / 99, v / v) system

[0069] Figure 7 The fluorescence emission spectra of BBNS before and after adding 17 metal ions to DMF / H2O (1 / 99, v / v) solution. 2+The fluorescence of BBNS in DMF / H2O (1 / 99, v / v) solution was quenched by about 3.5 times at a wavelength of 550 nm, indicating that BBNS may be used as a quenching Hg 2+ Fluorescent probes.

[0070] Example 16 BBNS fluorescence and Hg 2+ The relationship between the concentration

[0071] In the study of the fluorescence intensity of BBNS in DMF / H2O (1 / 99, v / v) solution and Hg 2+ The relationship between the concentrations of Hg and 2+ can completely quench the fluorescence of the solution ( Figure 8 a black group curve). Reducing Hg 2+ Concentrations of Hg ranging from 100 nM to 1 μM were studied. 2+ The effect of Hg on the fluorescence emission spectrum of BBNS showed that even 100 nM 2+ It can also quench about 3 / 4 of the fluorescence of BBNS ( Figure 8 a Red group curve). Continue to study 10-100 nM Hg 2+ The effect of 10 nM Hg on the fluorescence emission spectrum of BBNS was found 2+ can quench about 1 / 2 of the fluorescence of BBNS ( Figure 8 a Green group curve). Further study of 100 pM-10nM Hg 2+ The effect of Hg on the fluorescence emission spectrum of BBNS 2+ As the concentration increases, the fluorescence of BBNS gradually weakens ( Figure 8 a Blue group curve). BBNS to Hg 2+ The response reaches the picomolar level, which is ultrasensitive. 2+ From 0 to 7000 pM, the fluorescence intensity of BBNS decreases almost linearly ( Figure 8 b) has a switching characteristic. Therefore, BBNS can be used as a supersensitive Hg 2+ Fluorescent switch.

[0072] Example 17 Coexisting Metal Ions BBNS as a Hypersensitive Hg 2+ Effect of Fluorescence Switch

[0073] In order to investigate the effects of other coexisting metal ions on BBNS as a supersensitive Hg 2+ Interference of fluorescence switch in Hg 2 +In the BBNS solution, Ag was added + 、Al 3+ , Ca 2+ 、Cd 2+ 、Co 2+ Cr 3+ , Cu 2+ , Fe 2+ , Fe 3+ , K + Mg 2+ , Mn 2+ 、Na + 、Ni 2+ , Pb 2+ 、Zn 2+ A metal ion in the solution is added, and the maximum fluorescence intensity change of the solution before and after the addition of the ion is compared. Fig. 9 As shown in the figure, after adding coexisting metal ions, the maximum fluorescence intensity of the solution did not change significantly, indicating that these coexisting ions acted as a supersensitive Hg 2+ The fluorescent switch has little effect.

[0074] Example 18 BBNS as a hypersensitive Hg 2+ Fluorescent switch recyclability

[0075] like Fig.10 As shown, BBNS is fluorescent (on) in DMF / H2O (1 / 99, v / v) solution. 2+ The fluorescence of the solution was quenched (off), and then an excess of Na2S was added, and the fluorescence intensity of the solution rose to a level close to that of Hg 2+ and Na2S before fluorescence intensity (on), then Hg 2+ , the fluorescence of the solution was quenched again (off), and then an excess of Na2S was added, and the fluorescence of the solution was restored (on). 2+ The fluorescent switch has good cyclability; the amount of Na2S is 10 nM (i.e. 10000 pM).

[0076] In summary, the present application discloses a novel 1,8-naphthalene imide derivative, which can be used as a highly selective, highly sensitive, and highly anti-interference Hg 2+ Portable Hg test paper with colorimetric probe and naked eye indication 2+ Sensor, can also be used as Hg 2+ Ultrasensitive fluorescent switch.

Claims

1. A 1,8-naphthaleneimide derivative, the chemical structure of which is as follows: 。 2. The method for preparing the 1,8-naphthalimide derivative according to claim 1, characterized in that: The BBN compound is reacted with 2-aminothiazole to obtain a 1,8-naphthaleneimide derivative; the chemical structure of the BBN compound is as follows: 。 3. The method for preparing the 1,8-naphthalimide derivative according to claim 2, characterized in that: The reaction temperature is 100-150°C, and the reaction time is 1-5 hours.

4. The method for preparing the 1,8-naphthalimide derivative according to claim 2, characterized in that: The reaction is carried out in the presence of a noble metal catalyst, an inorganic base, an organic ligand, a solvent and an inert gas.

5. The method for preparing the 1,8-naphthalimide derivative according to claim 4, characterized in that: The noble metal catalyst includes a palladium catalyst; the inorganic base includes a cesium salt, a potassium salt, and a sodium salt; the organic ligand includes a phosphine ligand; and the solvent is an organic solvent.

6. The method for preparing the 1,8-naphthalimide derivative according to claim 4, characterized in that: The molar ratio of the BBN compound, 2-aminothiazole, the noble metal catalyst, the inorganic base and the organic ligand is 1:(1-2):(0.1-0.3):(1-2):(0.3-0.65).

7. The 1,8-naphthalimide derivative according to claim 1 is used as or in the preparation of Hg 2+ Application of colorimetric probe; or the 1,8-naphthalimide derivative according to claim 1 as or in the preparation of Hg 2+ Application of fluorescent switch.

8. Hg 2+ A detection sensor comprises the 1,8-naphthalimide derivative according to claim 1 and a substrate.

9. A non-disease diagnosis method for detecting Hg in liquid 2+ The method is characterized in that The 1,8-naphthaleneimide derivative according to claim 1 is used as an active substance to detect Hg in liquid by a colorimetric probe method, a fluorescence switch method or a sensor color change method. 2+ Detection.

10. The method for detecting Hg in a liquid for non-disease diagnosis according to claim 9. 2+ The method is characterized in that The method comprises the following steps: mixing the 1,8-naphthalimide derivative according to claim 1 with a detection liquid, and detecting Hg in the detection liquid according to the value of the absorbance ratio A525 / A435 at 525 nm and 435 nm. 2+ Qualitative and quantitative analysis; or mixing the 1,8-naphthaleneimide derivative according to claim 1 with a detection liquid, and detecting Hg in the liquid according to the fluorescence intensity at 550 nm 2+ Qualitative and quantitative analysis; or drop the detection liquid on the sensor containing the 1,8-naphthaleneimide derivative according to claim 1, and detect Hg in the liquid according to the color change of the sensor 2+ Qualitative and quantitative analysis.

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