New dimer-induced aie smart material and application thereof

Abstract

The application discloses a novel dimer-induced AIE smart material and application thereof, and a preparation method thereof, which comprises the following steps: mixing 4-methyl phthalic anhydride, 2-hydrazinyl benzothiazole and glacial acetic acid to react, and obtaining the novel dimer-induced AIE smart material. The novel dimer-induced AIE smart material is used as a probe to detect triethylamine and dichloromethane. The novel dimer-induced AIE smart material is used as an emission probe to quantitatively detect Zn 2+ . The novel dimer-induced AIE smart material can be used for on-site evaluation of freshness of beef and shrimps, and can be used for detection of Zn 2+ in a biological system.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of intelligent materials, and particularly relates to a novel dimer-induced AIE intelligent material and application thereof. BACKGROUND

[0002] In solving the problem of food safety, a key consideration is the development of urgent and indispensable monitoring systems. These systems need to have two basic prerequisites: simple operation, requiring not complicated steps; fast response speed, requiring fast and efficient detection capability. In addition, cost-effectiveness and high accuracy are overall parameters that must be prioritized when pursuing improved food safety measures. Rapid decomposition of amino acids in meat, seafood, etc. (such as some protein-rich foods) produces biogenic amines (BAs), due to the activity of external microorganisms or endogenous tissue metabolism during food spoilage. However, excessive intake of BAs can cause side effects such as headaches, blood pressure changes, respiratory disorders, and vomiting. Biogenic amines are important biomarkers for monitoring food quality and assisting in the diagnosis of diseases, therefore, simple, rapid, and accurate detection of food freshness is of great significance to ensure food safety and provides practical applications for food enterprises.

[0003] In biological and metabolic processes, including regulating the catalytic activity of enzymes and apoptosis, the essential trace element Zn 2+ (10-15 mg per day) is essential for the human body. However, a large intake of Zn 2+ may cause diseases such as digestive problems and impaired immunity. Therefore, there is an urgent need to develop a rapid, sensitive, and direct system to detect Zn 2 + in biological systems.

[0004] So far, most traditional fluorescent probes have the aggregation-caused quenching (ACQ) effect, and have no or weak fluorescence in the solid or aggregated state. Fortunately, the aggregation-induced emission (AIE) phenomenon discovered by Tang et al. in 2001 overcomes these problems, and in addition, external stimuli (such as heat, pressure, light, and vapor) can adjust the solid emission. Therefore, AIE materials with stimulus-responsive properties have attracted increasing attention for their potential applications in light-emitting diodes (LEDs), optoelectronic devices, sensors, and other fields. AIE sensors are sensitive to vapor stimuli and can detect food freshness and zinc ions (Zn 2+ ) through fluorescence colorimetric response. Therefore, there is an urgent need to develop new intelligent materials to support technologies with a wide range of practical applications in the field of material synthesis. SUMMARY

[0005] The technical problems to be solved by the present application are to provide a novel dimer-induced AIE smart material and its application in view of the deficiencies in the prior art.

[0006] To solve the above technical problems, the technical scheme of the present application is:

[0007] A novel dimer-induced AIE smart material has a structural formula as shown in the figure.

[0008]

[0009] As shown in the figure, a preparation method of the novel dimer-induced AIE smart material as described above comprises the following steps: Figure 1

[0010] 4-methylphthalic anhydride, 2-hydrazinobenzothiazole and glacial acetic acid are mixed and reacted to obtain the novel dimer-induced AIE smart material.

[0011] As a preferred solution, the molar ratio of the 4-methylphthalic anhydride to the 2-hydrazinobenzothiazole is 1:1.

[0012] The novel dimer-induced AIE smart material as described above is used as a probe to detect triethylamine and dichloromethane.

[0013] The novel dimer-induced AIE smart material as described above is used as a probe to detect triethylamine and dichloromethane.

[0014] A food freshness steam sensing paper comprises filter paper and the novel dimer-induced AIE smart material as described above, and the novel dimer-induced AIE smart material is attached to the filter paper.

[0015] A preparation method of the food freshness steam sensing paper as described above comprises the following steps:

[0016] 1) The novel dimer-induced AIE smart material is dissolved in ethanol to obtain a novel dimer-induced AIE smart material ethanol solution;

[0017] 2) The filter paper is soaked in the novel dimer-induced AIE smart material ethanol solution, and after being dried, the food freshness steam sensing paper is obtained.

[0018] As a preferred solution, the concentration of the novel dimer-induced AIE smart material ethanol solution is 10 μmol / L.

[0019] ​The novel dimer-induced AIE smart material of the present application exhibits AIE effect due to the dimer of the molecule, and exhibits strong green emission in solid state and in aqueous solution. After being fumigated by Et3N and CH2Cl2 vapor, the fluorescence of the novel dimer-induced AIE smart material changes from green to blue, which can be used for on-site evaluation of the freshness of beef and shrimp. In addition, the external Et3N / HAc vapor stimulation successfully realizes the cyclic blue-green emission, which can be used to make yellow-green fluorescent switches. In addition, in the EtOH / H2O (9 / 1, v / v) medium, the novel dimer-induced AIE smart material and Zn 2+ After interaction, the fluorescence changes from green to blue, which can be used for monitoring Zn 2+ . BRIEF DESCRIPTION OF DRAWINGS

[0020] Figure 1 The synthesis route map of the novel dimer-induced AIE smart material BTHM of the present application;

[0021] Figure 2 The nuclear magnetic resonance hydrogen spectrum of the novel dimer-induced AIE smart material BTHM of the present application;

[0022] Figure 3 The nuclear magnetic resonance carbon spectrum of the novel dimer-induced AIE smart material BTHM of the present application;

[0023] Figure 4 The unit cell diagram of the novel dimer-induced AIE smart material BTHM in a single crystal of the present application;

[0024] Figure 5 The pair filling pattern diagram of the novel dimer-induced AIE smart material BTHM in a single crystal of the present application;

[0025] Figure 6 The fluorescence image of the novel dimer-induced AIE smart material BTHM under different treatments of the present application;

[0026] Figure 7 The fluorescence spectrum diagram of the novel dimer-induced AIE smart material BTHM under different treatments of the present application;

[0027] Figure 8 The fluorescence spectrum diagram of the novel dimer-induced AIE smart material BTHM under the condition of cyclic fumigation of Et3N and HAc of the present application;

[0028] Figure 9 The pre-dyeing filter paper photo of the novel dimer-induced AIE smart material BTHM after fumigation treatment by CH2Cl2 vapor (a) and Et3N vapor (b) with different concentrations under 365 nm UV light of the present application;

[0029] Figure 10 PXRD images of BTHM powder, novel dimer-induced AIE smart material BTHM powder treated with CH2Cl2 steam, novel dimer-induced AIE smart material BTHM powder treated with Et3N steam, and novel dimer-induced AIE smart material BTHM powder treated with HAc steam.

[0030] Figure 11 Fourier transform infrared spectra of the novel dimer-induced AIE smart material BTHM powder, the novel dimer-induced AIE smart material BTHM powder treated with Et3N steam, the novel dimer-induced AIE smart material BTHM powder treated with CH2Cl2 steam, and the novel dimer-induced AIE smart material BTHM powder treated with Et3N steam and HAc steam sequentially.

[0031] Figure 12 The fluorescence changes of the food freshness steam sensing paper obtained in Example 2 of this invention after being placed in beef and shrimp for 0, 24, 48 and 72 hours (under 365nm UV light);

[0032] Figure 13 The fluorescence spectra of the novel dimer-induced AIE smart material BTHM at a concentration of 10 μmol / L in EtOH / H2O with different water contents are shown below.

[0033] Figure 14 for ) The fluorescence spectrum of this invention after adding various analytes (5 equal amounts) to an EtOH / H2O (9 / 1, v / v, pH=7.4) solution containing 10 μmol / L of the novel dimer-induced AIE smart material BTHM;

[0034] Figure 15 To illustrate this invention, different concentrations of Zn were added to an EtOH / H2O (9 / 1, v / v, pH = 7.4) solution containing 10 μmol / L of the novel dimer-induced AIE smart material BTHM. 2+ Emission spectrum (a) and BTHM-Zn at 465 nm blue light 2+ The fluorescence intensity value and the added Zn 2+ Equivalent number relationship diagram (b);

[0035] Figure 16Zn was added to the EtOH / H2O (9 / 1, v / v, pH=7.4) solution containing 10 μmol / L of the novel dimer-induced AIE smart material BTHM. 2+ After (5 equal volumes) and adding Zn to an EtOH / H2O (9 / 1, v / v, pH = 7.4) solution containing 10 μmol / L BTHM. 2+ Fluorescence spectra of (5 equal amounts) and various analytes (5 equal amounts);

[0036] Figure 17 Zn was added to an EtOH / H2O (9 / 1, v / v, pH = 7.4) solution containing 10 μmol / L of the novel dimer-induced AIE smart material BTHM at 465 nm blue light, according to the present invention. 2+ Fluorescence spectra of (5 equal volumes) solutions under pH 2–12 conditions;

[0037] Figure 18 Zn was added to both the EtOH / H2O (9 / 1, v / v, pH=7.4) solution containing 10 μmol / L of the novel dimer-induced AIE smart material BTHM and the EtOH / H2O (9 / 1, v / v, pH=7.4) solution containing 10 μmol / L of the novel dimer-induced AIE smart material BTHM. 2+ Fourier transform infrared spectra after (5 equal quantities);

[0038] Figure 19 Zn was added to both the EtOH / H2O (9 / 1, v / v, pH=7.4) solution containing 10 μmol / L of the novel dimer-induced AIE smart material BTHM and the EtOH / H2O (9 / 1, v / v, pH=7.4) solution containing 10 μmol / L of the novel dimer-induced AIE smart material BTHM. 2+ High-resolution mass spectra after (5 equal amounts);

[0039] Figure 20 Zn was added to both the EtOH / H2O (9 / 1, v / v, pH=7.4) solution containing 10 μmol / L of the novel dimer-induced AIE smart material BTHM and the EtOH / H2O (9 / 1, v / v, pH=7.4) solution containing 10 μmol / L of the novel dimer-induced AIE smart material BTHM. 2+ The working diagram after (5 equal quantities);

[0040] Figure 21 This is the electrostatic potential diagram of BTHM, the novel dimer-induced AIE smart material of this invention;

[0041] Figure 22 HOMO / LUMO energy level diagram of the new dimer-induced AIE smart material BTHM;

[0042] Figure 23 HOMO / LUMO energy level diagram of the new dimer-induced AIE smart material BTHM+Et3N;

[0043] Figure 24 HOMO / LUMO energy level diagram of the new dimer-induced AIE smart material BTHM+CH2Cl2;

[0044] Figure 25 HOMO / LUMO energy level diagram of the new dimer-induced AIE smart material BTHM+zinc ion;

[0045] Figure 26 Schematic diagram of the mechanism of action of the new dimer-induced AIE smart material BTHM on analytes;

[0046] Figure 27 Molecular Hirshfeld surface analysis diagram of the crystal structure of the new dimer-induced AIE smart material BTHM;

[0047] Figure 28 Total and decomposition fingerprint diagrams of the new dimer-induced AIE smart material BTHM;

[0048] Figure 29 Electron density diagram of the new dimer-induced AIE smart material BTHM;

[0049] Figure 30 A549 cell activity diagram after incubation of the new dimer-induced AIE smart material BTHM in EtOH / H2O (9 / 1, v / v, pH = 7.4) solution containing different concentrations of the new dimer-induced AIE smart material BTHM for 24 hours;

[0050] Figure 31 Fluorescence image of the new dimer-induced AIE smart material BTHM in A549 cells. DETAILED DESCRIPTION

[0051] The structural principles and working principles of the present application will be further described in detail below in conjunction with the accompanying drawings.

[0052] Example 1

[0053] Preparation of the new dimer-induced AIE smart material

[0054] The 4-methylphthalic anhydride (162 mg) and 2-hydrazinylbenzothiazole (165 mg) were added to 20 mL of glacial acetic acid and stirred under reflux for 5 h. After cooling and filtration, 168 mg of yellow solid (i.e. new dimer-induced AIE smart material BTHM) was isolated. The yield was 55.4%.

[0055] Example 2

[0056] Preparation of food freshness vapor sensing paper

[0057] The filter paper was cut into small pieces and soaked in a 10 μmol / L ethanol solution of the new dimer-induced AIE smart material BTHM obtained from Example 1. After drying, the food freshness vapor sensing paper was obtained.

[0058] Test Example 1

[0059] Hydrogen nuclear magnetic resonance

[0060] The new dimer-induced AIE smart material BTHM prepared in Example 1 was tested using a nuclear magnetic resonance spectrometer, and the results are shown in Figure 2 and Figure 3 .

[0061] Test Example 2

[0062] The new dimer-induced AIE smart material BTHM prepared in Example 1 was tested using an X-ray diffractometer, and the results are shown in Figure 4 and Figure 5 .

[0063] As can be seen from Figures 1 to 5 , two molecules in a single unit cell contain one HAc molecule. Hydrogen bonds are formed between the BTHM molecules and the HAc molecules. and Two strong intramolecular hydrogen bonds (O-H···N) are observed in each two adjacent BTHM molecules, which are combined together in an anti-parallel manner to form a special molecular dimer, with an intermolecular distance of The HAc molecules are connected to adjacent dimers through intermolecular hydrogen bond interactions to form a ladder-like structure.

[0064] Test Example 3

[0065] Stimulus response behavior and fluorescence switching experiment

[0066] 1) The new dimer-induced AIE smart material BTHM prepared in Example 1 was directly exposed to different samples, i.e. CH2Cl2vapor, Et3N vapor or HAc vapor; the test results are shown in Figure 6 .

[0067] 2) The new dimer-induced AIE smart material BTHM powder treated by different sample vapors, CH2Cl2 vapor, Et3N vapor or HAc vapor, was detected by a spectrofluorometer. The results are shown in Figure 7 .

[0068] 3) The new dimer-induced AIE smart material BTHM prepared by Example 1 was circulated fumigated in Et3N vapor and HAc vapor. The results are shown in Figure 8 .

[0069] As can be seen from Figure 6 , the new dimer-induced AIE smart material BTHM exhibits strong green emission with a maximum emission wavelength of 512 nm. As can be seen from Figure 7 , when the solid-state BTHM is fumigated by CH2Cl2 vapor, its initial green emission changes to blue-green (λem= 458 nm); when the solid-state BTHM is fumigated by Et3N vapor, its initial green emission changes to blue (λem= 460 nm), and when the solid-state BTHM is further contacted with Et3N vapor, the green fluorescence of the solid-state BTHM is restored. Moreover, when the solid-state BTHM is alternately fumigated by triethylamine and acetic acid vapor, the blue→green→blue fluorescence change phenomenon can be cyclically appeared, which can be used to make a green-blue fluorescence switch. As can be seen from Figure 8 , the emission change of blue→green→blue can be obviously observed, thereby exhibiting a vapor-controlled reversible solid-state stimulus-responsive blue→green→blue fluorescence switch.

[0070] Test Example 4

[0071] Emission response experiment

[0072] The food freshness vapor sensing paper obtained from Example 2 was treated by different concentrations of CH2Cl2 vapor and Et3N vapor (the concentrations were 0 μmol / L, 5 μmol / L, 10 μmol / L, 20 μmol / L, 30 μmol / L, 40 μmol / L and 50 μmol / L). The test results are shown in Figure 9 , (under UV light with a wavelength of 365 nm);

[0073] As can be seen from Figure 9 , the test paper emits green light, and after fumigation by CH2Cl2 vapor and Et3N vapor, its emission gradually changes from green to blue. These results show that BTHM can be used as a reliable candidate for detecting CH2Cl2 and Et3N vapor.

[0074] Test Example 5

[0075] The novel dimer-induced AIE smart material BTHM, prepared in Example 1, after treatment with CH2Cl2 steam, Et3N steam, and HAc steam, was tested using X-ray diffraction. The test results are as follows: Figure 10 As shown.

[0076] Depend on Figure 10 It can be seen that the peak intensity of the novel dimer-induced AIE smart material BTHM decreases after exposure to CH2Cl2 vapor and Et3N vapor, indicating that there is an interaction between CH2Cl2 and Et3N.

[0077] Test Example 6

[0078] The novel dimer-induced AIE smart material BTHM prepared in Example 1, after treatment with CH2Cl2 steam, Et3N steam, and sequential treatment with Et3N steam and HAc steam, was tested using Fourier transform infrared spectroscopy. The test results are as follows: Figure 11 As shown.

[0079] Depend on Figure 11 It can be seen that after treatment with CH2Cl2 vapor and Et3N vapor, the solution appears at 3456 cm⁻¹. -1 The weakening of the characteristic band corresponding to the -OH group indicates that hydrogen bonds have formed between CH2Cl2 and Et3N molecules with -OH groups, leading to a change in the molecular packing pattern in BTHM and potentially generating new aggregation forms. Furthermore, after exposure to Et3N vapor followed by fumigation with HAc vapor, the -OH characteristic band returned to its original intensity.

[0080] Test Example 7

[0081] Monitoring of food freshness

[0082] The food freshness steam sensing paper prepared in Example 2 was placed with meat and shrimp for 0, 24, 48, and 72 hours, respectively. The fluorescence changes of the food freshness steam sensing paper under UV light with a wavelength of 365 nm were then observed. The results are as follows: Figure 12 As shown.

[0083] Depend on Figure 12 It is known that as the biogenic amines from rotten pork and shrimp are used to fumigate BTHM test strips, the green fluorescence gradually turns blue. Therefore, BTHM test strips can be used to detect the freshness of food on-site.

[0084] Test Example 8

[0085] The new dimer-induced AIE smart material BTHM prepared from Example 1 was dissolved in ethanol to prepare EtOH / H2O system solution (10 μmol / L) with water content of 10%, 20%, 30%, 40%, 50%, 60%, 70%, 80%, 90%, and the AIE performance was tested by a fluorescence spectrometer, and the test results are shown in Figure 13 .

[0086] As can be seen from Figure 13 , the BTHM ethanol solution shows weak blue emission at 490 nm. However, as the water content increases to 20%, two new emission peaks at 425 nm and 500 nm are observed and the emission intensity is significantly increased. However, as the water content increases from 20% to 60%, the emission intensity gradually decreases. As the water content further increases (from 70% to 90%), a new emission peak appears at 510 nm, and the solution shows obvious green fluorescence, which is consistent with the solid-state emission. The results show that BTHM has AIE activity, and is caused by the formation of dimers.

[0087] Test Example 9

[0088] The new dimer-induced AIE smart material BTHM prepared from Example 1 was dissolved in ethanol to prepare a 1×10 -4 mol / L stock solution for later use. Then, the stock solution was diluted to prepare an ethanol / water (9 / 1, v / v, pH = 7.4) solution with a concentration of 10 μmol / L, 50 μmol / L of analytes were added, including GSH, Cys, Hcy, Gly, Met, Arg, Lys, Leu, Pro, Trp, Ser, Thr, Phe, Tyr, Val, His, Na + , K + , Mn 2+ , Co 2+ , Ni 2+ , Zn 2+ , Cd 2+ , Pb 2+ , Cr 3+ , CH3COO - , ClO - , and a sample solution was obtained; the sample solution was detected by a fluorescence spectrometer, and the test results are shown in Figure 14 .

[0089] As can be seen from Figure 14 , the addition of Zn 2+blue shift from 510 nm to 450 nm, a shoulder at 490 nm, and a clear green to blue change in solution fluorescence. However, the introduction of other analytes did not cause obvious changes in the fluorescence behavior of BTHM. Therefore, BTHM can detect Zn 2+ .

[0090] Test Example 10

[0091] 1) Detecting the sample solution with a fluorescence spectrometer;

[0092] The sample solution was a 10 μmol / L solution of the new dimer-induced AIE smart material BTHM prepared in Example 1 in ethanol / water (9 / 1, v / v, pH = 7.4) with a concentration of 10 μmol / L, to which 0-50 μmol / L of Zn 2+ .

[0093] 2) The detection results are shown in Figure 15 .

[0094] As shown in Figure 15 , the fluorescence intensity gradually increased at 465 nm as Zn 2+ was continuously added. The fluorescence intensity at 450 nm was proportional to the concentration of Zn 2+ . According to the formula DL = 3δ / S (δ: standard deviation of the blank measurement, S: slope of the calibration curve), the limit of detection (LOD) of Zn 2+ was estimated to be 7.18 x 10 -7 mol / L. This confirmed that BTHM can quantitatively detect Zn 2+ .

[0095] Test Example 11

[0096] A 10 μmol / L solution of the new dimer-induced AIE smart material BTHM prepared in Example 1 in ethanol / water (9 / 1, v / v, pH = 7.4) was prepared, and 50 μmol / L of Zn 2+ was added; analytes were added, including GSH, Cys, Hcy, Gly, Met, Arg, Lys, Leu, Pro, Trp, Ser, Thr, Phe, Tyr, Val, His, Na + , K + , Mn 2+ , Co 2+ , Ni 2+ , Zn 2+ , Cd 2+ , Pb 2+ , Cr 3+ , CH3COO -, ClO - The fluorescence intensity of BTHM at 450 nm was measured by a fluorescence spectrometer, and the results are shown in Figure 16 ;

[0097] As can be seen from Figure 16 , in the presence of other analytes, Zn 2+ can also cause significant changes in the fluorescence behavior of BTHM, indicating that BTHM has high sensitivity as a probe for Zn 2+ .

[0098] Test Example 12

[0099] A new dimer-induced AIE smart material BTHM prepared from Example 1 was used to prepare a BTHM ethanol / water (9 / 1, v / v, pH = 7.4) solution with a concentration of 10 μmol / L at pH 2-12, and the fluorescence spectra before and after the addition of 50 μmol / L Zn 2+ were detected by a fluorescence spectrometer, and the results are shown in Figure 17 .

[0100] As can be seen from Figure 17 , in the pH range of 7.0-9.0, after the addition of 50 μmol / L Zn 2+ , significant fluorescence was observed at 450 nm, confirming that BTHM can detect Zn 2+ under physiological conditions.

[0101] Test Example 13

[0102] The interaction between BTHM and Zn 2+ was detected by a Fourier infrared spectrometer, and the detection results are shown in Figure 18 ;

[0103] As can be seen from Figure 18 , after the interaction between BTHM and Zn 2+ , the characteristic absorption peak of the -OH group (3456 cm -1 ) became weaker, the characteristic absorption peaks of C=N and C=N red-shifted from 1665 cm -1 to 1720 cm -1 . The results show that deprotonation of -OH occurs, and Zn 2+ coordinates with the O atom of the -OH peak and the N atom of the benzothiazole.

[0104] Test Example 14

[0105] A new dimer-induced AIE smart material BTHM prepared from Example 1 was used to prepare a BTHM ethanol / water (9 / 1, v / v, pH = 7.4) solution with a concentration of 10 μmol / L, and 50 μmol / L of Zn 2+BTHM-Zn was analyzed using high-resolution mass spectrometry. 2+ The complex was detected, and the results are as follows: Figure 19 As shown.

[0106] Figure 19 Peaks at m / z of 310.06360 and 388.39325 can be observed and can be attributed to [BTHM+H]. + (calcdm / z:310.06502) and [BTHM-H+Zn 2+ +H2O] + (calcd m / z: 389.9891). These results indicate that BTHM-Zn 2+ system 2 +Contains one BTHM molecule and one Zn 2+ A single H2O molecule confirmed the interaction between BTHM and Zn. 2+ The ratio between them is 1:1.

[0107] Test Example 15

[0108] The novel dimer-induced AIE smart material BTHM prepared in Example 1 and Zn are kept together. 2+ The total concentration was 10 μmol / L, and Zn was prepared. 2+ Solutions with concentrations ranging from 0.1% to 0.9% were used to measure the fluorescence intensity at 450 nm using a fluorescence spectrometer. Corresponding working curves were plotted, and the results are as follows: Figure 20 As shown.

[0109] Depend on Figure 20 It can be seen that when Zn 2+ The system exhibits the strongest fluorescence at a concentration of 0.5%, indicating that BTHM and Zn... 2+ The complexation ratio was 1:1, consistent with the results of high-resolution mass spectrometry.

[0110] Test Example 16

[0111] Using BTHM and BTHM-Zn 2+ Theoretical calculations of the analyte were used to explain the sensing mechanism, and the results were as follows: Figures 21 to 26 As shown.

[0112] Figure 21The electrostatic potential map of BTHM calculated at the B3LYP / 6-31+G(d) level of theory is given, which describes that the heteroatoms of the 2-(benzo[d]thiazol-2-yl) moiety of BTHM except the endocyclic sulfur are electron-rich, while the carbon center and the sulfur center are electron-deficient. In addition, due to the presence of the carbonyl oxygen in BTHM, the 2-(benzo[d]thiazol-2-yl) moiety acts as a donor, while the 4-hydroxy-7-methylphthalazine-1(2H)-1 acts as an acceptor. In addition, the -OH group of the 4-hydroxy-7-methylphthalazine-1(2H)-1 fragment and the carbonyl oxygen and the endocyclic nitrogen of the 2-(benzo[d]thiazol-2-yl) fragment are the preferred sites for BTHM to form hydrogen bonds with other molecules and analytes. It can be seen from Figure 22 that the HOMO and LUMO orbitals of BTHM are asymmetric, with the HOMO orbital mainly located on the 2-(benzo[d]thiazol-2-yl) and the LUMO orbital mainly located on the 6-membered 4-hydroxy-7-methylphthalazine-1(2H)-1 due to its electron-withdrawing effect. However, the electron cloud shows that the electron density moving in the D→A direction is not completely separated, which indicates that the hybrid transition is caused by local excitation. It can be seen from Figure 23 and Figure 24 that the electron density distribution in the HOMO and LUMO maps of BTHM+analyte Et3N, CH2Cl2 and [Zn(H2O)] 2+ calculated according to the optimized conformation. In both cases, as with BHTM, the HOMO orbital is mainly located on the 2-(benzo[d]thiazol-2-yl), while the LUMO orbital is mainly located on the 6-membered 4-hydroxy-7-methylphthalazine-1(2H)-1 segment. However, compared with the original BTHM, the asymmetry in the electron distribution of BTHM+Et3N and BTHM+CH2Cl2 is relatively small. It can be seen from Figure 25 that the orbital distribution of BTHM+[Zn(H2O)] 2+ is essentially completely asymmetric, with the HOMO mainly located at the BTHM center and the LUMO located at the Zn 2+ center, which indicates that there is an energy interaction between BTHM and Zn 2+ during photoexcitation. On this basis, the working mechanism of BTHM to induce analytes, such as Figure 26As shown, the molecular design of BTHM promotes the D→A effect, endowing it with AIE properties. However, the intermolecular free volume can partially activate the intramolecular motion of BTHM, thereby inhibiting the AIE properties of BTHM in the test strip. The -OH group is the main interaction site for Et3N interaction, and the electrostatic interaction can be another driving force for this physical adsorption process. At low concentrations of biological amines (BAs), the hydrogen bond between BTHM and BA can partially block the electron transfer from the donor→acceptor, thereby reducing the ICT effect, while the local excitation is enhanced, resulting in a blue shift of fluorescence. In addition, the interaction of BTHM with Zn 2+ stops the rotation of the C-N single bond between 2-(benzo[d]thiazol-2-yl) and 4-hydroxy-7-methylphthalazine-1(2H)-1 segment, enhancing the AIE effect and increasing the emission intensity. Overall, the observed spectral changes in response to different analytes can be attributed to the synergistic effect of weakened ICT and enhanced AIE. This working mechanism is driven by intermolecular hydrogen bonds, which are highly related to steric hindrance and molecular geometry.

[0113] Test Example 17

[0114] The crystal structure of the novel dimer-induced AIE smart material BTHM obtained from Example 1 was analyzed by computer using molecular Hirshfeld surface analysis, and the results are shown in Figures 27 to 29 .

[0115] As Figure 27 can be seen, there are deep red circular grooves in the specific region of BTHM, where the analytes studied interact strongly. Figure 28 The total and decomposed fingerprint maps of BTHM indicate the presence of O··H, N··H and S·· interactions. The percentage contribution of O··H interaction is the largest (14.7%), which is manifested as a pair of unequal peaks in the region between the different regions of the full fingerprint 2D map. In addition, the N···H and S··H interactions are manifested as obvious pair of sharp peaks between and regions, with contributions of 7.6% and 4.5%, respectively. In combination Figures 27 to 29 , it can be seen that BTHM can exhibit interactions with molecular and cationic analytes from oxygen, nitrogen and sulfur centers, but the tendency to form O···H interactions is the largest compared to other interactions.

[0116] Test Example 18

[0117] MTT method for determining cell viability

[0118] A549 cells were seeded in 96-well plates and incubated at 37°C (5% CO2) for 24 h, then different concentrations of the novel dimer-induced AIE smart material BTHM (0, 2, 5, 10, 15, 20 μmol / L) prepared from Example 1 were added to the wells. After 24 h of incubation, 10 μL of MTT solution was added to each well, and incubated for another 4 h. The culture medium was removed, and the cell layer was dissolved in DMSO (100 μL). The absorbance was measured at 570 nm, and the test results are shown in Figure 30 .

[0119] As can be seen from Figure 30 , the BTHM at concentrations of 0, 5, 10, 15 and 20 μmol / L has no obvious effect on cell viability at about 24 h.

[0120] Test Example 19

[0121] A549 cells were cultured with DMEM added with 10% (v / v) fetal bovine serum. A549 cells were incubated with 10 μM of the novel dimer-induced AIE smart material BTHM prepared from Example 1 at 37°C for 30 min. After adding Zn 2+ (10 μM, 20 μM and 30 μM), the incubation was continued for another 30 min. All cell images were collected on a confocal scanning microscope, and the results are shown in Figure 31 .

[0122] As can be seen from Figure 31 , A549 cells emit strong fluorescence in the green channel after incubation with BTHM for 30 min. After further incubation in 10 μM, 20 μM and 30 μM Zn 2+ , obvious fluorescence enhancement was observed in the blue channel, and fluorescence weakening was observed in the green channel. Therefore, BTHM can be used for fluorescence colorimetric detection of Zn 2+ in living cells.

[0123] The above is only a preferred embodiment of the present application, and any slight modification, equivalent change and modification of the above embodiment according to the technical solution of the present application are within the scope of the technical solution of the present application.

Claims

1. The application of a dimer-induced AIE smart material in the preparation of a probe for detecting dichloromethane, characterized in that: The dimer-induced AIE smart material structure is as follows: 2.The application of the dimer-induced AIE smart material in the preparation of a probe for detecting dichloromethane according to claim 1, characterized in that: The preparation method of the dimer-induced AIE smart material comprises the following steps: 4-methylphthalic anhydride, 2-hydrazinobenzothiazole and glacial acetic acid are mixed to react to obtain the dimer-induced AIE smart material. 3.The application of the dimer-induced AIE smart material in the preparation of a probe for detecting dichloromethane according to claim 2, characterized in that: The molar ratio of the 4-methylphthalic anhydride to the 2-hydrazinobenzothiazole is 1:1.

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