A Fluorescent Probe for the Differential Detection of Copper and Mercury Ions, Its Preparation Method and Application

Abstract

The present invention relates to the field of optical sensing imaging detection technology, in particular to a fluorescent probe capable of differentially detecting copper and mercury ions, and a preparation method and application thereof. The fluorescent probe of the present invention has the structure shown in formula (I). The present invention also provides a preparation method thereof. The fluorescent probe provided by the present invention can achieve highly selective and highly sensitive multi-functional detection of Hg(II) and Cu(II), and the detection limit can reach the order of magnitude of 10-9 M; taking the fluorescent probe solution as a template, Hg(II) and Cu(II) as chemical input signals, and the fluorescence intensities at 485 and 595 nm as output signals, a combinational logic gate with NOR and INHIBIT functions is constructed.

Description

Technical Field

[0001] The present invention relates to the technical field of optical sensing imaging detection, in particular to a fluorescent probe for differential detection of copper and mercury ions, and a preparation method and application thereof. Background Art

[0002] Heavy metal ions are highly toxic, non-biodegradable and carcinogenic. They can enter the human body through the food chain and easily cause damage to the nervous system, kidney function, fertility, etc. Therefore, timely and accurate detection of heavy metal ions in water is an important means for ecological environment early warning and human health prevention and control.

[0003] Traditional analytical and testing methods such as atomic absorption and inductively coupled plasma mass spectrometry have high sensitivity and accuracy, but they have the disadvantages of requiring complex and expensive instruments, difficult operation, cumbersome sample pretreatment, and inability to perform real-time and on-line detection, so their application scope is limited. Fluorescence analysis methods have the advantages of high sensitivity and good selectivity and are widely used in the fields of environmental science and medicine. A large number of reports have been made on photochemical sensors based on the change of fluorescence performance induced by metal ions. Rhodamine dyes have excellent photophysical properties such as large molar extinction coefficient, high fluorescence quantum yield, and large absorption and emission wavelengths. Therefore, rhodamine-based fluorescent probes have attracted wide attention in the detection of Hg 2+ and Cu 2+ ions. However, the currently designed single fluorescent probe can only detect Hg 2+ or Cu 2+ alone and cannot achieve differential detection when two target metal ions coexist. Designing a fluorescent probe capable of selectively detecting copper and mercury ions is of great significance. Summary of the Invention

[0004] The purpose of the present invention is to provide a fluorescent probe for differential detection of copper and mercury ions, and a preparation method and application thereof.

[0005] To achieve this purpose, the present invention adopts the following technical solutions:

[0006] The first aspect of the present invention provides a fluorescent probe for differential detection of copper and mercury ions, and the specific technical solution is as follows:

[0007] A fluorescent probe for differential detection of copper and mercury ions has a structure shown in formula (I):

[0008]

[0009] Wherein, R is -CH2CH3 or -CH3.

[0010] The fluorescence probe for the differential detection of copper and mercury ions in the present invention is a terpyridine-rhodamine derivative, and its molecular structure is shown in formula (I). There are two response groups in its molecular structure, and the Hg 2+ and Cu 2+ ions in water can be detected by ratio fluorescence change (F595 / F485) and fluorescence quenching respectively. When the probe reacts with Hg 2+ , Hg 2+ induces the ring-opening and further hydrolysis of spirolactam, triggering the through-bond energy transfer (TBET) process. When the probe reacts with Cu 2+ ions, due to the binding of Cu 2+ to bipyridine, a ligand-to-metal charge transfer (LMCT) process occurs, causing fluorescence quenching. At the same time, it also effectively inhibits the TBET process induced by Hg 2+ ions and promotes the differential sensing of Cu(II) and Hg(II).

[0011] The second aspect of the present invention provides a preparation method of a fluorescence probe for the differential detection of copper and mercury ions, including the following steps:

[0012] First step, compound A and compound B are subjected to a condensation reaction to obtain compound TpRh;

[0013] Second step, compound TpRh and CH3OH are subjected to a hydrolysis reaction to obtain compound TpRhMe;

[0014] Third step, compound TpRhMe and hydrazine hydrate are subjected to a condensation reaction to obtain TpRhH;

[0015]

[0016] Wherein, R is -CH2CH3 or -CH3.

[0017] In some embodiments of the present invention, in the first step, the molar ratio of compound A to compound B is 1:0.8 - 1.2.

[0018] In some embodiments of the present invention, in the second step, the ratio of compound TpRh to CH3OH is 1 mmol: 8 - 12 mL.

[0019] In some embodiments of the present invention, in the third step, the molar ratio of compound TpRhMe to hydrazine hydrate is 1:2.8 - 3.2.

[0020] In some embodiments of the present invention, in the first step, after compound A and compound B are mixed, concentrated H2SO4 is added dropwise under cooling conditions.

[0021] In some embodiments of the present invention, in the first step, the reaction temperature is 85-95 °C and the reaction time is 8-16 h.

[0022] In some embodiments of the present invention, in the first step, after the reaction is completed, the reaction solution is poured into ice water, the pH is adjusted to neutral, extracted, dried, and concentrated to obtain a crude product, and further separated and purified to obtain the compound TpRh.

[0023] In some embodiments of the present invention, in the second step, the compound TpRh is dissolved in CH3OH, and concentrated H2SO4 is added dropwise with stirring under cooling conditions.

[0024] In some embodiments of the present invention, in the second step, the reaction temperature is 75-85 °C and the reaction time is 18-30 h.

[0025] In some embodiments of the present invention, in the second step, after the reaction is completed, CH3OH is removed, the reaction solution is poured into ice water, the pH is adjusted to neutral, extracted, dried, and concentrated to obtain a crude product, and further separated and purified to obtain the compound TpRhMe.

[0026] In some embodiments of the present invention, in the third step, the compound TpRhMe is dissolved in CH3OH, and hydrazine hydrate is added dropwise at room temperature.

[0027] In some embodiments of the present invention, in the third step, the reaction atmosphere is an inert gas, the reaction temperature is room temperature, and the reaction time is 4-8 h.

[0028] In some embodiments of the present invention, in the third step, after the reaction is completed, the reaction solution is cooled, centrifuged, and washed to obtain the compound TpRhH.

[0029] The third aspect of the present invention provides the above-mentioned fluorescent probe that can be used for the differential detection of copper and mercury ions in the fluorescence detection of Hg 2+ and / or Cu 2+ Application in fluorescence detection.

[0030] In some embodiments of the present invention, when applied to the fluorescence detection of Hg 2+ and / or Cu 2+ The fluorescent probe is dissolved in a solvent; the solvent includes water and an organic solvent, and the organic solvent is an organic solvent miscible with water.

[0031] The fourth aspect of the present invention provides the application of the above-mentioned fluorescent probe that can be used for the differential detection of copper and mercury ions in the construction of a molecular logic gate.

[0032] In some embodiments of the present invention, the molecular logic gate is a combined logic gate with NOR and INHIBIT functions. The fluorescent probe for the differential detection of copper and mercury ions in the present invention can detect Cu2+ and Hg 2+ For differential sensing, it can be applied to construct combinational logic gates with NOR and INHIBIT functions.

[0033] The method for constructing combinational logic gates with NOR and INHIBIT functions is as follows: using the fluorescent probe solution for differential detection of copper and mercury ions as a template, using Hg 2+ and Cu 2+ ions as chemical input signals, and using the fluorescence intensities at 485 and 595 nm as output signals to construct combinational logic gates with NOR and INHIBIT functions.

[0034] Compared with the prior art, the present invention has the following beneficial effects:

[0035] 1. The fluorescent probe provided by the present invention for differential detection of copper and mercury ions is ingeniously designed and has a simple structure. It can perform highly selective, highly sensitive, and ratio-responsive detection of Hg 2+ and Cu 2+ in aqueous solution, and the detection limit can reach the order of magnitude of 10 -9 M, having broad potential application value.

[0036] 2. The preparation method of the fluorescent probe provided by the present invention for differential detection of copper and mercury ions uses inexpensive and easily available raw materials, has a high yield, easy-to-control operating conditions, and low preparation cost, and is suitable for industrial production.

[0037] 3. The fluorescent probe provided by the present invention for differential detection of copper and mercury ions can have good responses and recognition effects on Hg 2+ and Cu 2+ Under different conditions, it can produce different fluorescence responses to Hg 2+ and Cu 2+ It has versatility in ion detection, can be used to construct molecular logic gates, and has good application prospects in the fields of fluorescent ion switches and sensors. BRIEF DESCRIPTION OF THE DRAWINGS

[0038] Figure 1 is the mass spectrum of the target product TpRh obtained in Example 1 of the present invention.

[0039] Figure 2 is the 1 H NMR (400 MHz) nuclear magnetic spectrum of the target product TpRh obtained in Example 1 of the present invention.

[0040] Figure 3 is the 13 C NMR (100 MHz) nuclear magnetic spectrum of the target product TpRh obtained in Example 1 of the present invention.

[0041] Figure 4 is the 1 1H NMR (400 MHz) NMR spectrum of the target product TpRhMe obtained in Example 2 of the present invention.

[0042] Figure 5 is the 13 13C NMR (100 MHz) NMR spectrum of the target product TpRhMe obtained in Example 2 of the present invention.

[0043] Figure 6 is the 1 1H NMR (400 MHz) NMR spectrum of the target product TpRhH obtained in Example 3 of the present invention.

[0044] Figure 7 is the 13 13C NMR (100 MHz) NMR spectrum of the target product TpRhH obtained in Example 3 of the present invention.

[0045] Figure 8 is the fluorescence emission spectrum diagram of the fluorescence probe obtained in Example 3 of the present invention for detecting different concentrations of Hg 2+ ions.

[0046] Figure 9 is the fluorescence emission spectrum diagram of the fluorescence probe obtained in Example 3 of the present invention for Hg 2+ , Cu 2+ and other metal ions.

[0047] Figure 10 is the bar chart of the fluorescence change (F595 / F485) of the fluorescence probe obtained in Example 3 of the present invention for different metal ions.

[0048] Figure 11 is the fluorescence emission spectrum diagram of the fluorescence probe obtained in Example 3 of the present invention for Hg 2+ and Cu 2+ ions.

[0049] Figure 12 is the fluorescence emission spectrum diagram of the fluorescence probe obtained in Example 3 of the present invention for Hg 2+ and Cu 2+ ions and the schematic diagram of the logic gate design. Detailed Description of the Invention

[0050] The following details a fluorescence probe for the differential detection of copper and mercury ions, its preparation method and application according to the present invention.

[0051] The first aspect of the present invention provides a fluorescence probe for the differential detection of copper and mercury ions, having the structure shown in formula (I):

[0052]

[0053] Among them, R is -CH2CH3 or -CH3.

[0054] The fluorescent probe for the differential detection of copper and mercury ions in the present invention is a terpyridine-rhodamine derivative, and its molecular structure is shown in formula (I). It is a white solid and does not emit light in the solid state. There are two response groups in its molecular structure, and the mercury in water can be detected by the ratio fluorescence change (F595 / F485) and fluorescence quenching respectively. 2+ and Cu 2+ ions. When the probe reacts with Hg 2 + ions, Hg 2+ induces the ring-opening and further hydrolysis of spirolactam, triggering the through-bond energy transfer (TBET) process. When the probe reacts with Cu 2+ ions, due to the binding of Cu 2+ to terpyridine, the ligand-to-metal charge transfer (LMCT) process occurs, causing fluorescence quenching. At the same time, it also effectively inhibits the TBET process induced by Hg 2+ ions, promoting the differential sensing of Cu 2+ and Hg 2+ .

[0055] The second aspect of the present invention provides a preparation method of a fluorescent probe for the differential detection of copper and mercury ions, including the following steps:

[0056] The first step: Compounds A and B are subjected to a condensation reaction to obtain compound TpRh;

[0057] The second step: Compound TpRh is subjected to a hydrolysis reaction with CH3OH to obtain compound TpRhMe;

[0058] The third step: Compound TpRhMe is subjected to a condensation reaction with hydrazine hydrate to obtain TpRhH;

[0059]

[0060] In some embodiments of the present invention, in the first step, the molar ratio of compound A to compound B is 1:0.8 - 1.2, preferably 1:0.9 - 1.1, and more preferably 1:1.

[0061] In some embodiments of the present invention, in the second step, the ratio of compound TpRh to CH3OH is 1 mmol: 8 - 12 mL, preferably 1 mmol: 9 - 11 mL, and more preferably 1 mmol: 10 mL.

[0062] In some embodiments of the present invention, in the third step, the molar ratio of compound TpRhMe to hydrazine hydrate is 1:2.8 - 3.2, preferably 1:2.9 - 3.1, and more preferably 1:3.

[0063] In some embodiments of the present invention, in the first step, after mixing compound A and compound B, concentrated H2SO4 is added dropwise under cooling conditions.

[0064] In some embodiments of the present invention, in the first step, the reaction temperature is 85 - 95 °C, which can be 85 - 90 °C, 90 - 85 °C, or can also be 88 - 92 °C, preferably 90 °C; the reaction time is 8 - 16 h, which can be 8 - 10 h, 10 - 12 h, 12 - 14 h, 14 - 16 h, or can also be 10 - 14 h, preferably 12 h.

[0065] In some embodiments of the present invention, in the first step, after the reaction is completed, the reaction solution is poured into ice water, the pH is adjusted to neutral, followed by extraction, drying, and concentration to obtain a crude product, and further separation and purification to obtain compound TpRh. In some preferred embodiments of the present invention, the pH is adjusted by adding an alkaline solution; the alkaline solution is selected from one or more of Na2CO3, NaHCO3, K2CO3, NaOH, and KOH solutions, preferably NaHCO3 solution. In some preferred embodiments of the present invention, the extraction is multiple extractions, and the extraction solvent is preferably CH2Cl2. In some preferred embodiments of the present invention, the drying is carried out with anhydrous Na2SO4. In some preferred embodiments of the present invention, the separation and purification is carried out using a silica gel chromatographic column; preferably, the eluent is PE / EtOAc = 15 / 1, v / v.

[0066] In some embodiments of the present invention, in the second step, compound TpRh is dissolved in CH3OH, and concentrated H2SO4 is added dropwise with stirring under cooling conditions.

[0067] In some embodiments of the present invention, in the second step, the reaction temperature is 75 - 85 °C, specifically it can be 75 - 80 °C, 80 - 85 °C, or can also be 78 - 82 °C, preferably 80 °C; the reaction time is 18 - 30 h, specifically it can be 18 - 24 h, 24 - 30 h, or can also be 22 - 28 h, preferably 24 h.

[0068] In some embodiments of the present invention, in the second step, after the reaction is completed, CH3OH is removed, the reaction solution is poured into ice water, the pH is adjusted to neutral, extracted, dried, and concentrated to obtain a crude product, which is further separated and purified to obtain the compound TpRhMe. In some preferred embodiments of the present invention, the pH is adjusted by adding an alkaline solution; the alkaline solution is selected from one or more of Na2CO3, NaHCO3, KCO3, NaOH, and KOH solutions, preferably NaHCO3 solution. In some preferred embodiments of the present invention, the extraction is multiple extractions, and the extraction solvent is preferably CH2Cl2. In some preferred embodiments of the present invention, the drying is carried out using anhydrous Na2SO4 or anhydrous MgSO4. In some preferred embodiments of the present invention, the separation and purification is carried out using a silica gel chromatography column; preferably, the eluent is CH2Cl2 / CH3OH = 40 / 1, v / v.

[0069] In some embodiments of the present invention, in the third step, the compound TpRhMe is dissolved in CH3OH, and hydrazine hydrate is added dropwise at room temperature.

[0070] In some embodiments of the present invention, in the third step, the reaction atmosphere is an inert gas, and the inert gas is selected from any one of nitrogen, argon, and helium; the reaction temperature is room temperature, the reaction time is 4 - 8 h, specifically it can be 4 - 5 h, 5 - 6 h, 6 - 7 h, 7 - 8 h, preferably 6 h.

[0071] In some embodiments of the present invention, in the third step, after the reaction is completed, the reaction solution is cooled, centrifuged, and washed to obtain the compound TpRhH.

[0072] The third aspect of the present invention provides the above-mentioned fluorescent probe that can be used for the differential detection of copper and mercury ions in the fluorescence detection of Hg 2+ and / or Cu 2+ applications.

[0073] In some embodiments of the present invention, when applied to the fluorescence detection of Hg 2+ and / or Cu 2+ the fluorescent probe is dissolved in a solvent; the solvent includes water and an organic solvent, and the organic solvent is an organic solvent miscible with water. Preferably, the organic solvent miscible with water is selected from one or more of ethanol, methanol, acetonitrile, acetone, dimethyl sulfoxide, tetrahydrofuran, and N,N-dimethylformamide, preferably N,N-dimethylformamide (DMF).

[0074] The fourth aspect of the present invention provides the above-mentioned fluorescent probe that can be used for the differential detection of copper and mercury ions in the application of constructing a molecular logic gate.

[0075] In some embodiments of the present invention, the molecular logic gate is a combinational logic gate with NOR and INHIBIT functions. The fluorescence probe for differentiating copper and mercury ions according to the present invention can distinguish and sense Cu 2+ and Hg 2+ and can be applied to construct a combinational logic gate with NOR and INHIBIT functions.

[0076] The method for constructing a combinational logic gate with NOR and INHIBIT functions is as follows: Using the fluorescence probe solution for differentiating copper and mercury ions as a template, and Hg 2+ and Cu 2+ ions as chemical input signals, the interaction between Hg 2+ and Cu 2+ ions and the probe compound TpRhH causes fluorescence changes and fluorescence quenching of the probe compound TpRhH at 485 and 595 nm. Taking the fluorescence intensities at 485 and 595 nm as output signals, a combinational logic gate with NOR and INHIBIT functions is constructed.

[0077] The following further details the specific embodiments of the present invention in conjunction with preferred embodiments. When the embodiment gives a numerical range, it should be understood that unless otherwise specified in the present invention, any value between the two endpoints of each numerical range and any value between the two endpoints can be selected. Unless otherwise defined, all technical and scientific terms used in the present invention have the same meaning as commonly understood by those skilled in the art of this technology. In addition to the specific methods, devices, and materials used in the embodiments, according to the knowledge of those skilled in the art of the prior art and the description of the present invention, any methods, devices, and materials similar or equivalent to those described in the embodiments of the present invention can also be used to implement the present invention.

[0078] The following takes R in formula (I) as -CH2CH3 as an example for illustration, and the synthesis route is as follows:

[0079]

[0080] Example 1: Synthesis of Compound TpRh

[0081] A mixture of compound B (3.25 g, 10 mmol) and compound A (3.13 g, 10 mmol) was added to a 50 mL round-bottom flask, and concentrated H2SO4 (6 mL, 98 wt%) was added dropwise under cooling conditions. The mixture was reacted at 90 °C for 12 hours. After the reaction was completed, the reaction solution was poured into an ice-water mixture, and NaHCO3 was added to adjust the pH of the solution to neutral. It was extracted several times with CH2Cl2, the organic phases were combined, dried over anhydrous Na2SO4, concentrated, and a crude product was obtained. The crude product was separated and purified by silica gel column chromatography (eluent: PE / EtOAc = 15 / 1, v / v) to obtain 4.86 g of a pink solid (compound TpRh), with a yield of 80.7%.

[0082] Mp: 251 - 253 °C. HRMS(ESI) calcd. m / z 602.2317 [M], found. m / z 602.2282 [M]. 1 1H NMR (400 MHz, CDCl3) δ 8.75 (s, 2H), 8.72 (d, J = 8.0 Hz, 2H), 8.66 (d, J = 8.0 Hz, 2H), 8.05 (d, J = 4.0 Hz, 1H), 7.86 (dd, J = 16.0, 8.0 Hz, 3H), 7.66 (dt, J = 24.0, 8.0 Hz, 2H), 7.53 (d, J = 8.0 Hz, 1H), 7.35 (dd, J = 8.0, 4.0 Hz, 2H), 7.24 (d, J = 8.0 Hz, 1H), 6.91 (d, J = 12.0 Hz, 1H), 6.63 (d, J = 8.0 Hz, 1H), 6.50 (d, J = 4.0 Hz, 1H), 6.40 (d, J = 8.0 Hz, 1H), 3.38 (q, J = 8.0 Hz, 4H), 1.20 (t, J = 8.0 Hz, 6H). 13 13C NMR (100 MHz, CDCl3) δ 198.6, 169.8, 166.6, 165.6, 156.3, 156.2, 154.1, 153.4, 153.0, 152.3, 145.0, 149.3, 149.0, 140.9, 137.0, 135.0, 134.6, 132.2, 130.4, 129.7, 129.3, 129.0, 128.9, 128.0, 127.1, 125.1, 124.2, 124.0, 122.2, 121.5, 120.2, 119.0, 116.0, 110.1, 108.7, 105.1, 103.8, 97.9, 97.3, 83.8, 52.4, 44.8, 12.8.

[0083] Example 2: Synthesis of compound TpRhMe

[0084] Dissolve the compound TpRh (0.60 g, 1 mmol) in CH3OH (10 mL). Under cooling conditions, while stirring, slowly add concentrated H2SO4 (1 mL) drop by drop, and reflux for 24 hours. After the reaction is completed, remove most of the CH3OH. Pour the residue into ice water, add NaHCO3 to adjust the pH of the solution to neutral, extract it several times with CH2Cl2, combine the organic phases, dry over anhydrous Na2SO4, and concentrate to obtain the crude product. The crude product is separated and purified by silica gel column chromatography (eluent: CH2Cl2 / CH3OH = 40 / 1, v / v) to obtain 0.48 g of a purple solid (compound TpRhMe), with a yield of 77.4%.

[0085] Mp: 193 - 195 °C. HRMS (ESI) calcd. m / z 617.2547 [M], found. m / z 617.2545 [M]. 1 1H NMR (400 MHz, DMSO-d6) δ 8.85 (s, 2H), 8.79 (d, J = 4.0 Hz, 2H), 8.71 (d, J = 7.6 Hz, 2H), 8.45 (d, J = 1.6 Hz, 1H), 8.37 (d, J = 8.0 Hz, 1H), 8.09 - 8.06 (m, 3H), 8.01 (dd, J = 8.8, 7.6 Hz, 1H), 7.93 (dd, J = 9.2, 8.0 Hz, 1H), 7.64 (d, J = 7.6 Hz, 1H), 7.58 - 7.55 (m, 2H), 7.47 (dd, J = 10.0, 1.6 Hz, 1H), 7.41 (d, J = 8.4 Hz, 1H), 7.31 (d, J = 2.0 Hz, 1H), 7.25 (d, J = 10.0 Hz, 1H), 3.90 - 3.83 (m, 4H), 3.62 (s, 3H), 1.34 (t, J = 7.2 Hz, 3H), 1.27 (t, J = 7.2 Hz, 3H). 13 13C NMR (100 MHz, DMSO-d6) δ 165.0, 158.7, 158.4, 158.3, 155.9, 154.4, 153.0, 149.4, 146.7, 144.8, 137.5, 133.6, 132.8, 132.3, 131.1, 130.6, 129.4, 129.2, 124.7, 121.6, 121.0, 119.8, 118.8, 118.3, 115.5, 96.7, 52.6, 47.0, 46.8, 13.3, 12.3.

[0086] Example 3: Synthesis of the compound TpRhH

[0087] Dissolve the compound TpRhMe (0.62 g, 1 mmol) in CH3OH (12 mL). Dropwise add hydrazine hydrate (0.15 g, 3 mmol) at room temperature under nitrogen protection. Reflux the reaction for 6 hours, and white solid is produced. After the reaction is completed, wait for the solution to cool, centrifuge, and wash with CH3OH to obtain 0.57 g of white solid (compound TpRhH) with a yield of 81.4%.

[0088] Mp: 294 - 296 °C. HRMS(ESI) calcd. m / z 617.2659 [M + H] + , found. m / z 617.2654 [M + H] + . 1 H NMR (400 MHz, CDCl3) δ 8.75 (s, 2H), 8.72 (d, J = 4.4 Hz, 2H), 8.66 (d, J = 8.0 Hz, 2H), 8.02 - 7.98 (m, 1H), 7.88 (t, J = 8.0 Hz, 2H), 7.80 (s, 1H), 7.50 (t, J = 5.2 Hz, 3H), 7.35 (dd, J = 6.8, 5.6 Hz, 2H), 7.15 - 7.13 (m, 1H), 6.82 (d, J = 8.0 Hz, 1H), 6.50 (dd, J = 13.2, 8.8 Hz, 2H), 6.35 (dd, J = 8.8, 1.6 Hz, 1H), 3.78 (s, 2H), 3.37 (q, J = 6.8 Hz, 4H), 1.19 (t, J = 6.8 Hz, 6H). 13 C NMR (100 MHz, CDCl3) δ 166.7, 156.3, 156.3, 153.6, 153.2, 151.3, 149.3, 149.1, 140.3, 137.0, 133.0, 129.8, 128.7, 128.1, 128.1, 124.0, 123.4, 122.4, 121.5, 120.0, 119.0, 116.1, 108.7, 104.2, 98.3, 65.8, 44.6, 12.7.

[0089] Example 4: Detection Limit

[0090] Prepare the probe TpRhH prepared in Example 3 into a DMF solution with a concentration of 5×10 -3 mol / L to obtain the probe mother liquor and store it for later use; take the probe mother liquor and dissolve it in H2O to prepare a test solution with a probe concentration of 10 -5 mol / L, 3 mL for each portion, a total of 2 portions. Respectively test the blank probe solution (i.e., the test solution), continuously add 0 - 80 μM of Hg 2+Fluorescence intensity of the test solution to be measured later, record the fluorescence emission spectrum. Ex(nm): 340.

[0091] Plot the fluorescence change (F595 / F485) against the concentration of Hg 2+ as shown in the inset of Figure 8 ), and the result is as shown in Figure 8 . Calculate the detection limit, which can reach the order of magnitude of 10 -9 M, with high sensitivity.

[0092] Example 5: Anti-interference experiment

[0093] Prepare the probe TpRhH prepared in Example 3 into a DMF solution with a concentration of 5×10 -3 mol / L to obtain the mother liquor of the probe, and store it for later use; take the mother liquor of the probe and dissolve it in H2O to prepare a test solution with a probe concentration of 10 -5 mol / L, 3 mL for each portion, a total of 20 portions. Measure the fluorescence intensity of the blank probe solution (i.e., the test solution), the test solution after adding 5 equivalents of Hg 2+ and different heavy metal solutions respectively, and record the fluorescence emission spectrum. Ex(nm): 340.

[0094] The results are as shown in Figure 9 and Figure 10 . It can be seen from Figure 9 that when only Hg 2+ is added to the test solution, the fluorescence at 595 nm increases; when only Cu 2+ is added to the test solution, the fluorescence at 485 nm quenches; when other ions are added to the test solution, the fluorescence intensity at 485 nm does not change. Plot a bar chart of the fluorescence change (F595 / F485) against different heavy metal types, as shown in Figure 10 . It can be seen that the probe compound TpRhH has high selectivity for Hg 2+ .

[0095] Example 6: Differential detection of Hg 2+ and Cu 2+

[0096] Prepare the probe TpRhH prepared in Example 3 into a DMF solution with a concentration of 5×10 -3 mol / L to obtain the mother liquor of the probe, and store it for later use; take the mother liquor of the probe and dissolve it in H2O to prepare a test solution with a probe concentration of 10 -5 mol / L, 3 mL for each portion, a total of 4 portions. Measure the blank probe solution (i.e., the test solution), the test solution after adding 5 equivalents of Hg 2+ respectively, the test solution after adding 5 equivalents of Hg 2+ respectively, and the test solution after adding 5 equivalents of Hg 2+ ​and Cu 2+ The fluorescence intensity of the test solution after [addition] was measured, and the fluorescence emission spectrum was recorded. Ex(nm): 340.

[0097] The fluorescence results of each group are as Figure 11 shown. When only Hg 2+ is added to the test solution, the fluorescence increases at 595 nm. When only Cu 2+ is added to the test solution, the fluorescence quenches at 485 nm. When both Hg 2+ and Cu 2+ are added to the test solution, the fluorescence quenches. It indicates that the probe TpRhH can detect Hg 2+ and Cu 2+ ions in water through ratiometric fluorescence changes (F595 / F485) and fluorescence quenching respectively, with high selectivity and high sensitivity.

[0098] Example 7: Construction of a combinational logic gate with NOR and INHIBIT functions

[0099] Using the probe solution prepared from the fluorescence probe for differentiating copper and mercury ions obtained in Example 3 as a template, with Hg 2+ and Cu 2+ divided into input signal 1 (Input 1) and input signal 2 (Input 2), and the fluorescence intensities (strong or weak) at 485 and 595 nm as output signal 1 (Output 1) (1 or 0) and output signal 2 (Output 2) (1 or 0) respectively. Combining the Hg 2+ and Cu 2+ ions with the probe compound TpRhH to form a combinational logic gate system with NOR and INHIBIT functions. Based on the fluorescence emission behaviors of each component in the system shown in Figure 8 , it can be seen that when there are no metal ions, the input signal is (0, 0), the system has strong fluorescence at 485 nm, and the output signal is (1, 0); when only Hg 2+ is present, the input signal is (1, 0), the system has strong fluorescence at 595 nm, and the output signal is (0, 1); when only Cu 2+ is present, the input signal is (0, 1), the system's fluorescence quenches at 485 nm, and the output signal is (0, 0); when both Hg 2+ and Cu 2+ are present, the input signal is (1, 1), the system's fluorescence quenches, and the output signal is (0, 0); its truth behavior is shown in Table 1 below. The principle of the combinational logic gate with NOR and INHIBIT functions is as Figure 12 shown.

[0100] Table 1 Truth table of the combinational logic gate with NOR and INHIBIT functions

[0101] Note: The word "addition" in the translation of line is added to make the sentence more complete and contextually meaningful, as the original Chinese seems to be missing some information about what is being added to the test solution.

[0102] The above embodiments are only illustrative of the principles and effects of the present invention, and are not intended to limit the present invention. Any person familiar with this technology can modify or change the above embodiments without departing from the spirit and scope of the present invention. Therefore, all equivalent modifications or changes made by those with ordinary knowledge in the technical field without departing from the spirit and technical ideas disclosed by the present invention should still be covered by the claims of the present invention.

Claims

1. A fluorescent probe for differential detection of copper and mercury ions, characterized in that, It has the structure shown in formula (I): Wherein, R is -CH2CH3 or -CH3.

2. A preparation method of a fluorescent probe for differential detection of copper and mercury ions, characterized in that, It includes the following steps: First step, compound A and compound B undergo a condensation reaction to obtain compound TpRh; Second step, compound TpRh undergoes a hydrolysis reaction with CH3OH to obtain compound TpRhMe; Third step, compound TpRhMe undergoes a condensation reaction with hydrazine hydrate to obtain TpRhH; Wherein, R is -CH2CH3 or -CH3.

3. The preparation method of the fluorescent probe for differential detection of copper and mercury ions as described in claim 2, characterized in that, It also includes one or more of the following features: a) In the first step, the molar ratio of compound A to compound B is 1:0.8 - 1.2; b) In the second step, the ratio of compound TpRh to CH3OH is 1 mmol: 8 - 12 mL; c) In the third step, the molar ratio of compound TpRhMe to hydrazine hydrate is 1:2.8 - 3.

2.

4. The preparation method of the fluorescent probe for differentiating copper and mercury ions as described in claim 2, characterized in that, It also includes one or more of the following features: 1) In the first step, after mixing compound A and compound B, concentrated H2SO4 is added dropwise under cooling conditions; 2) In the first step, the reaction temperature is 85 - 95 °C and the reaction time is 8 - 16 h; 3) In the first step, after the reaction is completed, the reaction solution is poured into ice water, the pH is adjusted to neutral, extracted, dried, concentrated to obtain a crude product, and further separated and purified to obtain compound TpRh.

5. The preparation method of the fluorescent probe for the differential detection of copper and mercury ions according to claim 2, characterized in that, It also includes one or more of the following features: 1) In the second step, compound TpRh is dissolved in CH3OH, and concentrated H2SO4 is added dropwise with stirring under cooling conditions; 2) In the second step, the reaction temperature is 75 - 85 °C and the reaction time is 18 - 30 h; 3) In the second step, after the reaction is completed, CH3OH is removed, the reaction solution is poured into ice water, the pH is adjusted to neutral, extracted, dried, concentrated to obtain a crude product, and further separated and purified to obtain compound TpRhMe.

6. The preparation method of the fluorescent probe for the differential detection of copper and mercury ions according to claim 2, characterized in that, It also includes one or more of the following features: 1) In the third step, compound TpRhMe is dissolved in CH3OH, and hydrazine hydrate is added dropwise at room temperature; 2) In the third step, the reaction atmosphere is an inert gas, the reaction temperature is room temperature, and the reaction time is 4 - 8 h; 3) In the third step, after the reaction is completed, the reaction solution is cooled, centrifuged, and washed to obtain compound TpRhH.

7. The fluorescent probe for differential detection of copper and mercury ions as described in claim 1 or the fluorescent probe for differential detection of copper and mercury ions prepared according to any one of claims 2 to 6 in the fluorescence detection for non-diagnostic purposes of Hg 2+ and / or Cu 2+ ions.

8. The application according to claim 7, characterized in that, The fluorescent probe is dissolved in a solvent; the solvent includes water and an organic solvent, and the organic solvent is an organic solvent miscible with water.

9. Use of the fluorescent probe for differential detection of copper and mercury ions according to claim 1 or the fluorescent probe for differential detection of copper and mercury ions prepared according to any one of claims 2 - 6 in constructing a molecular logic gate.

10. The application according to claim 9, characterized in that, The molecular logic gate is a combinational logic gate with NOR and INHIBIT functions.

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