Novel camphor-based ratiometric fluorescent probe for detecting hypochlorous acid as well as preparation method and application of novel camphor-based ratiometric fluorescent probe

Abstract

The invention discloses a novel camphor-based ratiometric fluorescent probe for detecting hypochlorous acid as well as a preparation method and application of the novel camphor-based ratiometric fluorescent probe. The fluorescent probe is 3-((10-n-butyl-10H-phenothiazin-3-yl) methylene)-1, 7, 7-trimethylbicyclo [2.2. 1] heptyl-2-one, which is called CP-SO for short, and the fluorescent probe has the structural formula shown in the specification. The probe CP-SO can specifically recognize hypochlorous acid, hypochlorous acid is added into a solution containing the probe CP-SO, and the color of the solution is rapidly changed from yellow to transparent and colorless under sunlight. Meanwhile, the fluorescence emission spectrum of the probe CP-SO has obvious blue shift, the fluorescence emission wavelength of the probe CP-SO is shifted from 543 nm to 492 nm, and the ratio of F492 nm to F543 nm is obviously increased. In addition, the probe shows good selectivity and anti-interference performance on hypochlorous acid, and is not influenced by other cations, anions, biological mercaptan, active oxygen and the like. Therefore, the compound can be used as a fluorescent probe for detecting hypochlorous acid and has a good application prospect.

Description

Technical Field

[0001] The invention belongs to the technical field of fluorescent probes and relates to a novel camphor-based ratiometric fluorescent probe for detecting hypochlorous acid, a preparation method thereof and an application thereof. Background Art

[0002] Reactive oxygen species, as important intracellular signaling molecules, play a crucial role in the human body. Hypochlorous acid, produced by the reaction of chloride ions and hydrogen peroxide catalyzed by myeloperoxidase in leukocytes under certain physiological conditions, is one of the most important reactive oxygen species in biological systems. It plays a vital role in organisms, killing pathogens and bacteria that invade organisms and protecting human health. However, excessive hypochlorous acid can lead to tissue damage, inflammation, and a range of diseases, such as cardiovascular disease, neurodegenerative diseases, cancer, and autoimmune diseases. Therefore, it is of great significance to develop a highly selective, sensitive, and real-time method for monitoring hypochlorous acid in the human body and the environment.

[0003] Traditional methods for detecting hypochlorous acid include colorimetry, iodine titration, electrochemistry, and chemiluminescence. While these methods can detect hypochlorous acid to a certain extent, they suffer from drawbacks such as complex operation, low sensitivity, poor selectivity, and an inability to achieve real-time monitoring. Fluorescent probes, due to their advantages of rapid detection, high sensitivity, good selectivity, and simple operation, have found widespread application in fields such as life sciences, environmental science, and food science. The CP-SO fluorescent probe for detecting hypochlorous acid, synthesized using camphor as a raw material, boasts a wide detection range, high sensitivity, and good selectivity, making it of great significance for hypochlorous acid detection. Summary of the Invention

[0004] In view of the shortcomings of the prior art, the technical problem to be solved by the present invention is to provide a new camphor-based ratiometric fluorescent probe for detecting hypochlorous acid, as well as its preparation method and application, which can detect hypochlorous acid with high sensitivity and high selectivity to meet the requirements for detecting hypochlorous acid.

[0005] In order to solve the above technical problems, the technical solution adopted by the present invention is:

[0006] A new camphor-based ratiometric fluorescent probe for the detection of hypochlorous acid is 3-((10-n-butyl-10H-phenothiazin-3-yl)methylene)-1,7,7-trimethylbicyclo[2.2.1]heptan-2-one (CP-SO for short), with the molecular formula: C 27 H 31 NOS, the structural formula is:

[0007]

[0008] The method for preparing the novel camphor-based ratiometric fluorescent probe for detecting hypochlorous acid specifically comprises the following steps:

[0009] (1) 1-3 mmol of compound CP-S, 1-3 mmol of camphor, and 1.5-2.5 mmol of potassium tert-butoxide were dissolved in 20-25 mL of tert-butanol and added to a round-bottom flask. The reaction mixture was reacted at 45°C for 24-48 hours and monitored by TLC until the reaction of the raw materials was complete.

[0010] (2) After the reaction is completed, 100-200 mL of ethyl acetate is added to the reaction mixture, which is then washed with distilled water. The organic phase is dried and distilled, and the resulting crude product is purified by silica gel column (petroleum ether: dichloromethane = 60:1, v / v) to obtain a yellow solid compound CP-SO.

[0011] The probe CP-SO selectively interacts with hypochlorous acid. Upon addition of hypochlorous acid to a solution of the probe CP-SO, the solution rapidly changes color from yellow to transparent and colorless under sunlight. Furthermore, its fluorescence emission spectrum undergoes a significant blue shift, from 543 nm to 492 nm, with a detection limit as low as 35 nM.

[0012] Beneficial Effects: Compared with the prior art, the novel camphor-based ratiometric fluorescent probe CP-SO of the present invention rapidly changes the color of the probe solution from yellow to transparent and colorless in the presence of hypochlorous acid, and the fluorescence emission spectrum undergoes a significant blue shift, making it suitable for highly sensitive detection of hypochlorous acid. Furthermore, the fluorescent probe exhibits excellent selectivity and anti-interference capabilities for hypochlorous acid, and is unaffected by interfering substances such as other cations, anions, reactive oxygen species, and reactive sulfur species. As a fluorescent probe for detecting hypochlorous acid, CP-SO offers numerous advantages, including ease of synthesis, rapid response, high sensitivity, and good selectivity, and possesses promising application value. BRIEF DESCRIPTION OF THE DRAWINGS

[0013] Figure 1 This is the fluorescence spectrum of CP-SO reacting with hypochlorous acid at different concentrations;

[0014] Figure 2 is the histogram of the fluorescence intensity ratio after the interaction of CP-SO with other interfering substances; DETAILED DESCRIPTION

[0015] The present invention will be further described below with reference to specific embodiments.

[0016] Example 1

[0017] The preparation of the novel camphor-based ratiometric fluorescent probe CP-SO for detecting hypochlorous acid is as follows:

[0018]

[0019] The specific steps are as follows:

[0020] (1) Dissolve 1 mmol of compound CP-S, 1 mmol of camphor, and 1.5 mmol of potassium tert-butoxide in 20 mL of tert-butanol in a 100 mL reaction flask. Stir and react at 45°C for 24 h. Monitor the reaction by TLC until the reaction is complete.

[0021] (2) After the reaction, 100 mL of ethyl acetate was added to the reaction mixture, which was then washed with distilled water. The organic phase was dried and distilled, and the resulting crude product was purified by silica gel column (petroleum ether: dichloromethane = 60:1, v / v) to obtain a yellow solid compound CP-SO. 1 H NMR (600MHz, DMSO-d6) δ7.39 (d, J=8.5Hz, 1H), 7.30 (s, 1H), 7.20 (q, J=7.2Hz, 1H), 7.14 (d , J=7.5Hz, 1H), 7.05 (t, J=7.9Hz, 2H), 6.99 (s, 1H), 6.96 (t, J=7.5Hz, 1H), 3.89 (t, J=7.0Hz ,2H), 3.11(d, J=4.3Hz, 1H), 2.15(tt, J=11.6, 4.6Hz, 1H), 1.76(t, J=11.0Hz, 1H), 1.67(p, J=7.0Hz, 2H), 1.41 (tt, J=24.2, 14.0Hz, 4H), 0.96 (s, 3H), 0.93-0.83 (m, 6H), 0.71 (s, 3H); 13 C NMR (150MHz, CDCl3) δ129.77, 127.63, 115.14, 57.02, 49.19, 43.32, 30.81, 29.94, 27.07, 20.56, 20.15, 19.16, 18.39, 13.82, 9.32.

[0022] Example 2

[0023] CP-SO was made into 2×10 -5 M PBS buffer solution (containing 30% DMF), 10 M sodium hypochlorite solution was diluted with distilled water to concentrations of 0, 2×10 -6 , 4×10 -6 , 6×10 -6 , 8×10 -6 , 8×10 -6 , 1×10 -5 , 1.2×10 -5 , 1.4×10 -5 , 1.7×10 -5 , 2.0×10 -5 , 2.5×10 -5M solution, add different concentrations of hypochlorous acid solution to the probe solution. Fluorescence spectrum titration method is used to measure the fluorescence emission spectrum of CP-SO in the presence of different concentrations of hypochlorous acid using a fluorescence spectrophotometer. Figure 1 It can be seen that with the addition of hypochlorous acid, the intensity of the emission peak of CP-SO at 543nm is greatly weakened, while the emission peak at 492nm is significantly enhanced. And with the increase of hypochlorous acid concentration, the fluorescence intensity of the probe is higher than that of F 492nm / F 543nm This indicates that the compound can be used as a fluorescent probe for detecting hypochlorous acid.

[0024] Example 3

[0025] CP-SO was prepared into 2×10 -5 M solution (containing 30% DMF), and different active oxygen, active sulfur and other anions were dissolved in the aqueous solution to a concentration of 2×10 -4 The fluorescence emission intensity ratio F of the probe in the presence of different active oxygen, active sulfur, cations and anions was determined by fluorescence spectrophotometer using fluorescence spectrophotometer. 492nm / F 543nm The results are as follows Figure 2 As shown in Figure 2, only the addition of hypochlorous acid caused the emission wavelength of the probe to blue shift, and the fluorescence intensity was significantly higher than that of F 492nm / F 543nm The fluorescence intensity ratio of the probe increased significantly, while the fluorescence intensity ratio of other analytes did not change significantly. This shows that the compound can be used as a fluorescent probe for the specific detection of hypochlorous acid.

Claims

1. A novel camphor-based ratiometric fluorescent probe for detecting hypochlorous acid, and its preparation method and application, characterized in that: The molecular formula of the probe is: C 27 H 31 NOS, the structural formula is:

2. A method for preparing a novel camphor-based ratiometric fluorescent probe for detecting hypochlorous acid as described in claim 1, characterized in that: 10-n-butyl-10H-phenothiazine-3-carboxaldehyde (abbreviated as CP-S) is condensed with camphor to obtain the probe 3-((10-n-butyl-10H-phenothiazine-3-yl)methylene)-1,7,7-trimethylbicyclo[2.2.1s heptan-2-one, abbreviated as CP-SO).

3. The specific preparation method of the novel camphor-based ratiometric fluorescent probe for detecting hypochlorous acid according to claim 2 comprises: (1) 1-3 mmol of compound CP-S, 1-3 mmol of camphor, and 1.5-2.5 mmol of potassium tert-butoxide were dissolved in 20-25 mL of tert-butanol and added to a reaction flask. The reaction mixture was reacted at 45°C for 24-48 hours and monitored by TLC until the raw materials were completely reacted. (2) After the reaction is completed, 100-200 mL of ethyl acetate is added to the reaction mixture, which is then washed with distilled water. The organic phase is dried and distilled, and the resulting crude product is purified by silica gel column (petroleum ether: dichloromethane = 60:1, v / v) to obtain a yellow solid compound CP-SO.

4. Use of the novel camphor-based ratiometric fluorescent probe CP-SO according to claim 1 in detecting hypochlorous acid.

5. The use according to claim 4, characterized in that The probe CP-SO can selectively react with hypochlorous acid. The solution color quickly changes from yellow to colorless and transparent under sunlight. In addition, the fluorescence emission spectrum of the probe CP-SO undergoes a significant blue shift, with the fluorescence emission wavelength shifting from 543nm to 492nm, and F 492nm / F 543nm The ratio increased significantly, the detection limit was as low as 35nM, and the response time was within 10s.

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