Bisphenol A thiophosphorylhydrazine silver, zinc and cadmium ion fluorescent probe

Abstract

The invention discloses a bisphenol A thiophosphoric hydrazide silver, zinc and cadmium ion fluorescent probe, which is specifically characterized in that bisphenol A and hexamethylenetetramine are subjected to Duff hydroformylation reaction under acidic conditions to obtain a bisphenol A dialdehyde compound, and meanwhile, diphenyl phosphine chloride and sublimed sulfur are subjected to sulfuration reaction to obtain an intermediate 1; carrying out substitution reaction on 1 and hydrazine hydrate to obtain an intermediate 2, and carrying out amine-aldehyde condensation reaction on the intermediate 2 and a bisphenol A dialdehyde compound to obtain the probe DPSN. The fluorescent probe disclosed by the invention is a chemical fluorescent sensor which is rapid in response and high in specific recognition, can be used for detecting trace Ag < + >, Zn < 2 + > and Cd < 2 + > in an environment, has relatively good practical application and popularization values, and is easy in preparation raw material obtaining, simple in synthesis and high in yield.

Description

Technical Field

[0001] The invention relates to a bisphenol A thiophosphonohydrazide type silver, zinc and cadmium ion fluorescent probe, and specifically belongs to the technical field of organic fluorescent functional materials. Background Art

[0002] Silver, zinc and cadmium are widely used in human production and life. At present, silver is widely used in the electronics, food and pharmaceutical industries. The industrial wastewater produced by this will release a large amount of pollutants into the environment. As one of the heavy metal ions, silver ions can form a strong bond with some microorganisms, thereby affecting the respiration of microorganisms and causing apoptosis. Long-term exposure to silver will cause the skin surface to appear blue-gray, and high levels of Ag in the body will cause the skin to become yellow-gray. + Can cause toxicological symptoms such as silver protein / silver protein disease, hypotension and skin diseases.

[0003] Zinc is an essential trace element for the human body. It plays an important role in various biological systems such as gene expression and neurotransmission. When the human body lacks a certain amount of zinc, it will also lead to growth retardation, immune deficiency and nervous system dysfunction. On the contrary, excessive intake of zinc will also disrupt various metabolic processes and induce cell apoptosis, and increase the incidence of cardiovascular diseases. Zinc in the environment mainly comes from zinc mining, machinery manufacturing, etc. 2+ The excessive presence of metal ions will make the soil inactive, leading to heavy metal ion pollution.

[0004] Unlike silver and zinc, cadmium is one of the most toxic and harmful heavy metals. Today, cadmium and its related compounds are classified as Class 1 carcinogens. Metallic cadmium is widely used in industrial and agricultural processes, including electroplating, metallurgy, and military industry. Cadmium is not an essential element for the human body. Cadmium in the human body is generally enriched from the external environment. Long-term intake of cadmium ions will cause great harm to human health, leading to Itai-itai disease, kidney damage, and prostate cancer.

[0005] Therefore, highly sensitive detection of the above three metal ions in water, natural environment and organisms is of great significance to ecological environment protection and human health. However, the current methods based on metal ion detection mainly include spectrophotometry, inductively coupled plasma analysis and atomic absorption spectroscopy. These testing methods generally have disadvantages such as inconvenient operation, high cost and slow signal response. Fluorescence analysis has attracted widespread attention due to its advantages such as high sensitivity, simple operation and low testing cost. Currently reported methods that can be used to monitor Ag + Most of the fluorescence sensors are fluorescence quenching, and a few are fluorescence enhancement and have color-changing effects. For example, in 2023, Hongqi Li et al. developed a coumarin-based large Stokes shift sensor that can detect Hg 2+ and Ag + The fluorescent probe monitored by+ It shows fluorescence quenching phenomenon. (Li, HQ; Yan, JB; Jiang, L.; Zhao, Y.; Song, YX; Yu, JR; Cheng, L., Selective and Sensitive Detection of Hg 2+ and Ag + by a Fluorescent and Colorimetric Probe with LargeStokes Shift. [J]. Journal of Fluorescence. 2023) ; for the reported ability to simultaneously monitor Zn 2+ and Cd 2+ Fluorescent probes are often accompanied by fluorescence quenching of multiple other ions. For example, in 2018, Jia Li et al. developed a fluorescent probe based on isophthalaldehyde and benzothiazole for detecting Zn 2+ and Cd 2+ The fluorescent probe, which is 2+ and Cd 2+ After that, the fluorescence color of the solution changed from orange to green. However, a total of 18 ions were detected, of which 8 ions had slight quenching and 4 ions had complete quenching. (J. Li, YH Chen, TT Chen, J. Qiang, ZJ Zhang, TW Wei, W. Zhang, F. Wang, XQ Chen, A benzothiazole-basedfluorescent probe for efficient detection and discrimination of Zn 2+ and Cd 2+ , using cysteine ​​as an auxiliary reagent. [J]. Sensors and Actuators B:Chemical. 2018, 268, 446-455). Summary of the invention

[0006] In order to overcome the shortcomings of the prior art, the present invention aims to provide a new bisphenol A thiophosphonohydrazide silver, zinc and cadmium ion fluorescent probe and its preparation method, which can be used for Ag + 、Zn 2+ and Cd 2+ Rapid identification and detection of different metal ions.

[0007] Bisphenol A thiophosphonohydrazide Ag of the present invention + 、Zn 2+ and Cd 2+ Fluorescent probes have the characteristics of multiple responses, rapid response time, wide pH range, convenient and fast detection, and significant identification effect.

[0008] The chemical structural formula of the bisphenol A thiophosphonohydrazide silver, zinc and cadmium ion fluorescent probe of the present invention is: ; The preparation method of the fluorescent probe is as follows: Step 1: Dissolve bisphenol A and hexamethylenetetramine in trifluoroacetic acid, heat under reflux for reaction for 3 to 4 hours, cool to room temperature after the reaction is completed, add hydrochloric acid while stirring to acidify, extract the product with ethyl acetate, and wash the obtained organic phase with water, dry it with anhydrous sodium sulfate, evaporate it, and separate it with column chromatography to obtain bisphenol A dialdehyde; Step 2: Under an argon atmosphere, sublimed sulfur was added to diphenylphosphine chloride, and the mixture was heated under reflux for 0.5 h to obtain intermediate 1; Step 3: add anhydrous ethanol to the intermediate 1, then slowly add hydrazine hydrate, heat to reflux for 2 to 3 hours, cool to room temperature, and then filter and wash with deionized water to obtain the intermediate 2; Step 4: After the intermediate 2 and bisphenol A dialdehyde are heated to reflux in anhydrous ethanol for 4 to 6 hours, they are cooled to room temperature, filtered, and recrystallized from ethanol to obtain bisphenol A thiophosphonohydrazide-based silver, zinc and cadmium ion fluorescent probes (DPSN).

[0009] In the step 1, the equivalent ratio of bisphenol A to hexamethylenetetramine is 1:7, and the eluent for column chromatography separation is petroleum ether / ethyl acetate in a volume ratio of 10:1.

[0010] In the step 2, the equivalent ratio of sublimed sulfur to diphenylphosphine chloride is 1:1, and the reaction temperature is 150°C.

[0011] In the step 3, the equivalent ratio of the intermediate 1 to hydrazine hydrate is 1:10, and the mass concentration of hydrazine hydrate is 80%.

[0012] In the step 4, the equivalent ratio of the intermediate 2 to bisphenol A dialdehyde is 2:1.

[0013] The reaction equation of the bisphenol A thiophosphonohydrazide silver, zinc and cadmium ion fluorescent probe of the present invention is as follows: ; DPSN is the target fluorescent probe molecule.

[0014] Beneficial effects of the present invention: 1. The fluorescent probe of the present invention is added with Ag in a MeOH / H2O mixed solution (methanol and aqueous solution). + After that, the fluorescence changes to yellow-green fluorescence, or when Zn is added 2+ After that, the fluorescence turns bright blue, or Cd is added 2+ The fluorescence then turns blue, which can be clearly distinguished from other metal ions. It responds quickly and is a chemical fluorescence sensor with high specificity.

[0015] 2. The fluorescent probe of the present invention is effective for Ag + 、Zn 2+ and Cd 2+ The detection limits are very low, reaching 1.01×10 -7 M, 4.26×10 -6 M and 6.91×10 -6 M, high sensitivity, can be used for trace environments and water systems Ag + 、Zn 2+ and Cd 2+ The qualitative and quantitative analysis and detection of ion concentration has very good practical application value.

[0016] 3. The raw materials for preparing the fluorescent probe of the present invention are easily available, the synthesis is simple and the yield is high. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 :The fluorescent probe prepared by the present invention and the addition of Ag + The UV spectrum after Figure 2 : Fluorescence emission spectra of the fluorescent probe prepared by the present invention after reacting with different metal ions; Figure 3 :The fluorescent probe prepared by the present invention is added with different concentrations of Ag + Fluorescence emission spectrum after action; Figure 4 :The fluorescent probe prepared by the present invention is added with different concentrations of Ag + Concentration fitting curve diagram; Figure 5 :The fluorescent probe prepared by the present invention is added with different concentrations of Zn 2+ Fluorescence emission spectrum after action; Figure 6 :The fluorescent probe prepared by the present invention is added with different concentrations of Zn 2+ Concentration fitting curve diagram; Figure 7 :The fluorescent probe prepared by the present invention is added with different concentrations of Cd 2+ Fluorescence emission spectrum after action; Figure 8 :The fluorescent probe prepared by the present invention is added with different concentrations of Cd2+ Concentration fitting curve diagram; Fig. 9 : The fluorescent probe DPSN-Ag prepared by the present invention + Job's Plot graph; Fig.10 : The fluorescent probe DPSN-Zn prepared by the present invention 2+ Job's Plot graph; Fig.11 : The fluorescent probe DPSN-Cd prepared by the present invention 2+ Job's Plot graph; Fig.12 : The fluorescent probe DPSN-Ag prepared by the present invention + Ion competition column spectrum of Fig.13 : The fluorescent probe DPSN-Zn prepared by the present invention 2+ Ion competition column spectrum of Fig.14 : The fluorescent probe DPSN-Cd prepared by the present invention 2+ Ion competition column spectrum of Fig.15 : The fluorescent probes DPSN and DPSN-Ag prepared by the present invention + Fluorescence change diagram in different pH ranges; Fig.16 : The fluorescent probes DPSN and DPSN-Zn prepared by the present invention 2+ Fluorescence change diagram in different pH ranges; Fig.17 : The fluorescent probes DPSN and DPSN-Cd prepared by the present invention 2+ Fluorescence change diagram in different pH ranges; Fig.18 : The nuclear magnetic proton spectrum of the fluorescent probe prepared by the present invention ( 1 H-NMR) spectra; Fig.19 : Mass spectrum of the fluorescent probe prepared by the present invention. DETAILED DESCRIPTION

[0018] Example 1 Preparation of Bisphenol A Thiophosphonohydrazide-Based Fluorescent Probes for Silver, Zinc and Cadmium Ions Synthesis of Bisphenol A Dialdehyde: To a round-bottom flask containing bisphenol A (2.2829 g, 10 mmol) and hexamethylenetetramine (9.8133 g, 70 mmol) was gradually added 30 mL of trifluoroacetic acid. The reaction temperature was 75°C and the mixture was heated under reflux for 3 h. The reaction progress was monitored by TLC thin-layer chromatography. After the reaction was completed, the mixture was cooled to room temperature and 50 mL of 1M HCl aqueous solution was added dropwise and stirred at room temperature for 30 min. The resulting mixture was extracted three times with 50 mL of ethyl acetate. The organic phases were combined, washed three times with saturated brine, dried over anhydrous sodium sulfate, and concentrated by rotary evaporation to remove the ethyl acetate solvent. The resulting crude product was separated and purified by column chromatography (eluent: ethyl acetate: petroleum ether = 1:10, v / v) to obtain bisphenol A dialdehyde as a white needle-shaped solid (1.5980 g, yield 70%).

[0019] Synthesis of intermediate 1: Under argon atmosphere, diphenylphosphine chloride (0.4518 g, 2.05 mmol) and sublimed sulfur (0.0657 g, 2.05 mmol) were added into a 50 mL round-bottom flask in sequence without adding other solvents. The reaction was carried out at 150 °C for 0.5 h. The reaction progress was monitored by TLC thin-layer chromatography. After the reaction, a yellow oily liquid, namely intermediate 1, was obtained.

[0020] Synthesis of intermediate 2: Directly add 15 mL of anhydrous ethanol to the round-bottom flask containing intermediate 1, and then slowly add 2 mL of hydrazine hydrate compound (mass fraction 80%). The mixture is refluxed at 85 °C for 2 h, and a light yellow precipitate appears. After cooling to room temperature, the precipitate is filtered under reduced pressure, washed with deionized water several times, and dried to obtain a light yellow solid, namely intermediate 2 (0.3992 g, yield 78.5%).

[0021] Synthesis of probe DPSN: Intermediate 2 (0.2483 g, 1 mmol) and bisphenol A dialdehyde (0.1422 g, 0.5 mmol) were dissolved in 10 mL of anhydrous ethanol and heated under reflux at 80°C for 6 h. After the reaction was completed as monitored by TLC thin layer chromatography, the solution was cooled to room temperature and filtered to obtain bisphenol A thiophosphonohydrazide fluorescent probe DPSN (0.3382 g, yield 86.6%).

[0022] 1 H NMR (500 MHz, Chloroform- d ) δ 9.72 (s, 2H), 7.89 (dd, J= 13.9,7.6 Hz, 8H), 7.77 (s, 2H), 7.53 (d, J = 7.5 Hz, 4H), 7.47 (q, J = 6.8, 5.9Hz, 8H), 7.02 (d, J = 8.6 Hz, 2H), 6.86 (s, 2H), 6.72 (d, J = 8.6 Hz, 2H),6.59 (d, J = 16.9 Hz, 2H), 1.56 (s, 6H).ESI-MS calculated for C 41 H 38 N4O2P2S2,744.85, found(m / z), 744.8[M] + .

[0023] Example 2 UV Detection of Bisphenol A Thiophosphonohydrazide Fluorescent Probe DPSN Weigh 0.0372 g of fluorescent probe DPSN, dissolve it in methanol solvent (MeOH) and dilute it to 50 mL in a volumetric flask to prepare a solution with a concentration of 1 mmol / L, i.e., the fluorescent probe DPSN stock solution.

[0024] The test was carried out in a MeOH: H2O = 3: 1 (v / v) solution system. 150 μL of the fluorescent probe DPSN stock solution and 2100 μL of MeOH solution were added to 21 5 mL centrifuge tubes. No metal ion solution was added to one centrifuge tube to form a blank control. 750 μL of 1 mmol / L metal ion solution including Li+ was added to the remaining 20 centrifuge tubes. + , Na + ,Mg 2+ , Al 3+ , K + , Ca 2+ ,Cr 3+ , Mn 2+ , Fe 2+ , Fe 3+ ,Co 2+ , Ni 2+ , Cu 2+ , Zn 2+ , Ag + , Cd 2+ , Ba 2+ , Hg 2+ , Ce 3 + , Zr4+ After being mixed evenly, they were transferred to a 1 cm × 1 cm standard quartz cuvette and their UV spectra were measured.

[0025] The probe dilution without metal ions is colorless and visible to the naked eye. + The detection solution turned into light brown, and the whole spectrum was scanned with UV-visible spectrophotometer. Figure 1 DPSN+Ag + The detection solution showed a new absorption peak at 346 nm.

[0026] Example 3 Fluorescence Selective Determination of Bisphenol A Thiophosphonohydrazide Fluorescent Probe DPSN The test was carried out in a MeOH: H2O = 3: 1 (v / v) solution system. 150 μL of the fluorescent probe DPSN stock solution and 2100 μL of MeOH solution were added to 21 5 mL centrifuge tubes. No metal ion solution was added to one centrifuge tube to form a blank control. 750 μL of 1 mmol / L metal ion solution including Li+ was added to the remaining 20 centrifuge tubes. + , Na + ,Mg 2+ , Al 3+ , K + , Ca 2+ ,Cr 3+ , Mn 2+ , Fe 2+ , Fe 3+ ,Co 2+ , Ni 2+ , Cu 2+ , Zn 2+ , Ag + , Cd 2+ , Ba 2+ , Hg 2+ , Ce 3 + , Zr 4+ After being mixed evenly, they were transferred to a 1 cm × 1 cm standard quartz cuvette and the change curves of their fluorescence spectra were measured respectively.

[0027] The fluorescence detection effect of the fluorescent probe DPSN on different metal ions is as follows Figure 2 As shown. The experiment shows that the fluorescent probe molecule is + 、Zn 2+ and Cd 2+ After the combination, they all showed obvious fluorescence color change and enhancement, among which Ag + The fluorescence color changes from light purple to yellow-green, Zn2+ and Cd 2+ The fluorescence color of the DPSN fluorescent probe changes from light purple to blue. + 、Zn 2+ and Cd 2+ There are different fluorescence selectivity effects.

[0028] Example 4 Fluorescence titration experiment of bisphenol A thiophosphonohydrazide fluorescent probe DPSN on three ions The test was carried out in a MeOH: H2O = 3: 1 (v / v) solution system. Three groups of 5 mL centrifuge tubes were taken and 60 μL of the above fluorescent probe DPSN stock solution was added to the 5 mL centrifuge tubes. Different proportions of Ag + The second group added different proportions of Zn 2+ The third group added different proportions of Cd 2+ Stock solution (0.9 eq ~ 10 eq).

[0029] The fluorescence increase was detected by fluorescence spectrometer at 349 nm excitation wavelength (e.g. Figure 3 As shown in the figure), the fluorescence intensity of the probe increases with the + The concentration increases with the increase of Ag + The maximum fluorescence intensity is reached when the concentration is . + ] / 10 -5 M is the horizontal axis, and the fluorescence intensity at 535 nm is the vertical axis. Draw a linear fitting curve (such as Figure 4 The minimum detection limit (LOD) was calculated to be 1.01×10 -7 M.

[0030] like Figure 5 As shown in Figure 2, the fluorescence intensity of the probe increases with the increase of Zn 2+ The concentration increases with the increase of Zn 2+ The maximum fluorescence intensity was reached when the concentration was 0. 2+ ] / 10 -5 M is the horizontal axis, and the fluorescence intensity at 477 nm is the vertical axis. Draw a linear fitting curve (such as Figure 6 According to the slope of the linear fitting line of the scatter plot, the minimum detection limit (LOD) was calculated to be 4.26×10 -6 M.

[0031] like Figure 7 As shown, the fluorescence intensity of the probe increases with the2+ The concentration increases with the increase of Cd 2+ The maximum fluorescence intensity is reached when the concentration is . 2+ ] / 10 -5 M is the horizontal axis, and the fluorescence intensity at 473 nm is the vertical axis. Draw a linear fitting curve (such as Figure 8 According to the slope of the linear fitting line of the scatter plot, the minimum detection limit (LOD) was calculated to be 6.91×10 -6 M.

[0032] Example 5 Job's Plot curves of bisphenol A thiophosphonohydrazide fluorescent probe DPSN for three ions The test was carried out in a MeOH: H2O = 3: 1 (v / v) solution system. The sum of the concentrations of the control probe DPSN and the ions was 200 μM, and the ratios of the fluorescent probe DPSN and the ions were 1:9, 2:8, 3:7, 4:6, 5:5, 6:4, 7:3, 8:2, and 9:1, respectively.

[0033] The fluorescence intensity at 535 nm was detected by fluorescence spectrometer under an excitation wavelength of 349 nm. Fig. 9 As shown, [DPSN] / {[DPSN]+[Ag + ]}The fluorescence intensity reaches the maximum around 0.33, and the increase of Ag + The fluorescence intensity of the ratio decreases, such as Fig.10 As shown, the fluorescence intensity at 477 nm was detected, [DPSN] / {[DPSN]+[Zn 2+ ]}The fluorescence intensity reaches the maximum around 0.33, and the increase of Zn 2+ The fluorescence intensity of the ratio decreases, such as Fig.11 As shown, the fluorescence intensity at 473 nm was detected, and it can be seen that [DPSN] / {[DPSN]+[Cd 2+] The fluorescence intensity reaches the maximum around 0.33, and the increase of Cd 2+ The fluorescence intensity of the probe DPSN and Ag decreased. + 、Zn 2+ and Cd 2+ The complexation ratio is 1:2.

[0034] Example 6 Anti-interference detection of three ions by bisphenol A thiophosphonohydrazide fluorescent probe DPSN Ag +For example, in the MeOH: H2O = 3: 1 (v / v) solution system, 40 5 mL centrifuge tubes were divided into two groups, A and B, with 20 centrifuge tubes in each group. In group A, 60 μL of 1 mmol / L DPSN stock solution, 2190 μL of MeOH solution and 450 μL of aqueous solution were added to each centrifuge tube. The solution in the first centrifuge tube was used as the blank group, and 300 μL of 1 mmol / L Li + 、Na + Mg 2+ 、Al 3+ , K + , Ca 2+ Cr 3+ , Mn 2+ , Fe 2 + , Fe 3+ 、Co 2+ 、Ni 2+ , Cu 2+ 、Zn 2+ 、Cd 2+ , Ba 2+ , Hg 2+ 、Ce 3+ and Zr 4+ In each centrifuge tube in group B, 60 μL of 1 mmol / L DPSN stock solution, 2190 μL of MeOH solution, and 300 μL of 1 mmol / L Ag were added. + The solution in the first centrifuge tube was used as a blank group, and 300 μL of 1 mmol / L Li was added to each of the other 19 centrifuge tubes. + 、Na + Mg 2+ 、Al 3+ , K + , Ca 2+ Cr 3+ , Mn 2+ , Fe 2+ , Fe 3+ 、Co 2+ 、Ni 2+ , Cu 2+ 、Zn 2+ 、Cd 2 + , Ba 2+ , Hg 2+ 、Ce 3+ and Zr 4+ After mixing evenly, measure the fluorescence intensity value at the maximum emission wavelength of 535 nm.

[0035] Zn 2+ and Cd 2+ The test method of refers to that of silver ions, and the fluorescence values ​​of the two at their maximum emission wavelengths are measured respectively. Figure 12-14 As shown, it shows that DPSN has good anti-interference ability in the presence of different metal ions after combining with these three ions. Fig.12 It can be seen that when there is Ag in the solution + and Zn 2+ or Ag + and Cd 2+ When the solution is Ag + Therefore, the fluorescence probe DPSN is effective for Ag + The anti-interference performance is higher than that of Zn 2+ and Cd 2+ The same is true for Zn 2+ and Cd 2+ In the comparison of the anti-interference performance of the two, according to Fig.13 and Fig.14 It can be seen that DPSN has a significant effect on Zn 2+ The anti-interference performance is higher than that of Cd 2+ .

[0036] Example 7 Fluorescence changes of bisphenol A thiophosphonohydrazide fluorescent probe DPSN and ions at different pH The test was carried out in a MeOH: H2O = 3: 1 (v / v) solution system. Four groups of test solvents with pH values ​​of 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, and 12 were prepared. The first group was tested by adding 60 μL of the above-mentioned fluorescent probe DPSN stock solution; the second group was tested by adding 60 μL of the above-mentioned fluorescent probe DPSN stock solution and 300 μL of the above-mentioned Ag + The third group added 60 μL of the above fluorescent probe DPSN stock solution and 300 μL of the above Zn 2+ The fourth group added 60 μL of the above fluorescent probe DPSN stock solution and 300 μL of the above Cd 2+ Stock solution. The fluorescence values ​​at 535 nm, 477 nm and 473 nm were measured by fluorescence spectrometer at an excitation wavelength of 349 nm, and a dot-line graph was drawn (such as Fig.15 , Fig.16 and Fig.17 ). Detection of Ag by fluorescent probe DPSN + The pH range of application is 6 ~ 10. The fluorescent probe DPSN detects Zn 2+ The pH range of application is 5 ~ 10. The fluorescent probe DPSN detects Cd2+ The applicable pH range is: 5 ~ 10.

Claims

1. A bisphenol A thiophosphonohydrazide silver, zinc and cadmium ion fluorescent probe, characterized in that: The chemical structural formula of the fluorescent probe is: 。 2. A bisphenol A thiophosphonohydrazide silver, zinc and cadmium ion fluorescent probe according to claim 1, characterized in that: The preparation method of the fluorescent probe is as follows: Step 1: Dissolve bisphenol A and hexamethylenetetramine in trifluoroacetic acid, heat under reflux for reaction for 3 to 4 hours, cool to room temperature after the reaction is completed, add hydrochloric acid while stirring to acidify, extract the product with ethyl acetate, and wash the obtained organic phase with water, dry it with anhydrous sodium sulfate, evaporate it, and separate it with column chromatography to obtain bisphenol A dialdehyde; Step 2: Under an argon atmosphere, sublimed sulfur was added to diphenylphosphine chloride and heated under reflux for 0.5 h to obtain intermediate 1; Step 3: add anhydrous ethanol to the intermediate 1, then slowly add hydrazine hydrate, heat to reflux for 2 to 3 hours, cool to room temperature, and then filter and wash with deionized water to obtain the intermediate 2; Step 4: After the intermediate 2 and bisphenol A dialdehyde are heated to reflux in anhydrous ethanol for 4 to 6 hours, they are cooled to room temperature, filtered, and recrystallized from ethanol to obtain bisphenol A thiophosphonohydrazide silver, zinc, and cadmium ion fluorescent probes.

3. A bisphenol A thiophosphonohydrazide silver, zinc and cadmium ion fluorescent probe according to claim 2, characterized in that: In the step 1, the equivalent ratio of bisphenol A to hexamethylenetetramine is 1:7, and the eluent for column chromatography separation is petroleum ether / ethyl acetate in a volume ratio of 10:

1.

4. A bisphenol A thiophosphonohydrazide silver, zinc and cadmium ion fluorescent probe according to claim 2, characterized in that: In the step 2, the equivalent ratio of sublimed sulfur to diphenylphosphine chloride is 1:1, and the reaction temperature is 150°C.

5. A bisphenol A thiophosphonohydrazide silver, zinc and cadmium ion fluorescent probe according to claim 2, characterized in that: In the step 3, the equivalent ratio of intermediate 1 to hydrazine hydrate is 1:10, and the mass concentration of hydrazine hydrate is 80%.

6. A bisphenol A thiophosphonohydrazide silver, zinc and cadmium ion fluorescent probe according to claim 2, characterized in that: In the step 4, the equivalent ratio of the intermediate 2 to bisphenol A dialdehyde is 2:1.

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