Fluorescent composite material, use method and sensor using fluorescent composite material

Abstract

The invention relates to a fluorescent composite material, a use method and a sensor using the fluorescent composite material, and relates to the technical field of fluorescent materials.The fluorescent composite material comprises the steps of synthesis of TPB-DMTP, synthesis of TPB-DMTP at S-CDs and synthesis of TPB-DMTP at S-CDs / MnO2. According to the fluorescent composite material, the application method thereof and the sensor pair using the fluorescent composite material, multielement organophosphorus pesticides and organophosphorus pesticides in natural samples can be rapidly recognized on portable equipment.

Description

Technical Field

[0001] The present invention relates to the technical field of fluorescent materials, and in particular to a fluorescent composite material, a use method and a sensor using the same. Background Art

[0002] Organophosphate pesticides (OPs) are widely used insecticides that effectively disrupt nerve cell signaling in pests. However, the abuse and environmental residues of OPs have attracted wide attention because they affect the human nervous system by inhibiting the activity of acetylcholinesterase. In the laboratory, gas chromatography and high-performance liquid chromatography are commonly used for the detection and classification of OPs. Portable devices based on nanofluorescence or electrochemical methods may be suitable for on-site OPs detection, but they focus on single OPs species or the total amount of OPs.

[0003] However, identifying trace levels of OPs residues is a challenge in the implementation of these methods. Summary of the invention

[0004] In order to enable rapid identification of trace levels of OPs on a portable device, the present invention provides a fluorescent composite material, a method of using the same, and a sensor using the same.

[0005] In a first aspect, the present invention provides a fluorescent composite material, which is prepared by the following steps: S1. Synthesis of TPB-DMTP: S11. At room temperature, 0.021 g of 1,3,5-tris(4-aminophenyl)benzene (TAPB) was dissolved in 9 mL of a mixture of 1,4-dioxane, butanol, and methanol, wherein the volume ratio of the 1,4-dioxane, butanol, and methanol was 4:4:1, to obtain a mixed solution A. S12, adding 0.0174 g of 2,5-dimethoxybenzaldehyde (DMTP) to the mixed solution A, and ultrasonicating for 20 minutes to obtain a mixed solution B; S13, heating the mixed solution B to 70° C. for 24 h, while adding 12 M acetic acid twice at an interval of 2 hours, with the first amount of acetic acid added being 0.1 mL and the second amount of acetic acid added being 0.9 mL, to obtain a mixed solution C; S14. Naturally cool the mixed solution C to 25° C. and centrifuge it at 5000 rpm for 15 minutes to separate the TPB-DMTP precipitate. Wash the TPB-DMTP precipitate with tetrahydrofuran and acetone, and then dry it under vacuum to obtain TPB-DMTP.

[0006] S2. Synthesis of TPB-DMTP@S-CDs: S21, heating a mixture of 4 g thiourea, 2 g citric acid and 20 mL N,N-dimethylformamide to 160° C. for 6 hours to obtain a mixed solution D; S22, the mixed solution D cooled naturally to room temperature was mixed with 40mL 50mg mL −1 100 mL of NaOH and 40 mL of 5% by volume HCl were mixed, stirred for 5 minutes, centrifuged at 16000 rpm for 15 minutes, the obtained product was washed with water, and freeze-dried at -40°C for 18 hours to obtain S-CDs; S23, 5 mL 4-12 μg mL −1 of TPB-DMTP and 5 mL 0.5 μg mL −1 The sulfur-doped carbon quantum (S-CDs) was stirred for 12 h to obtain TPB-DMTP@S-CDs suspension; Synthesis of S3, TPB-DMTP@S-CDs / MnO2: S31, add 1.5 mL of 1-100 μM potassium permanganate (KMnO4) and 1.5 mL of 1 mM 2-morpholineethanesulfonic acid (MES) to 2 mL of TPB-DMTP@S-CDs suspension to adjust the pH value of the TPB-DMTP@S-CDs suspension to pH=6 to obtain a mixed solution E; S32. At room temperature, the mixed solution E was ultrasonically treated for about 30 minutes until a brown colloid was formed; the brown colloid was centrifuged at a rotation speed of 5000 rpm for 20 minutes to obtain a TPB-DMTP@S-CDs / MnO2 fluorescent composite material.

[0007] By adopting the above technical solutions, the fluorescence detection method has the characteristics of high sensitivity and rapid response, and can detect trace OPs at a low price. The new fluorescent nanomaterials, including covalent organic frameworks (COFs) and carbon dots (CDs), have abundant active sites, high biocompatibility and excellent skeleton stability, which can significantly improve the fluorescence signal excited by OPs. The COF obtained from triphenylbenzene (TPB) and dimethoxyterephthalaldehyde (DMTP) exhibits stable fluorescence properties due to radiative transitions and large Stokes shifts, while sulfur-doped carbon quantum dots (S-CDs) exhibit a strong fluorescence from n−π * The fluorescence spectra of COF (TPB-DMTP) and S-CDs are independent and there is no fluorescence quenching between them, thus ensuring the dual-wavelength fluorescence source. Under 410 nm excitation, TPB-DMTP@S-CDs exhibited much stronger fluorescence (F) than TPB-DMTP and S-CDs at 530 nm. 530 ), which indicates that the coexistence of TPB-DMTP and S-CDs can enhance the fluorescence of TPB-DMTP via the surface plasmon effect, and under 560 nm excitation, the combination of TPB-DMTP and S-CDs enhances the fluorescence of S-CDs at 610 nm (F 610 ) is still obvious, For TPB-DMTP@S-CDs / MnO2 prepared with KMnO4, due to the introduction of F 530 and F 610 The peak intensity is reduced, and the enzymatic product of acetylcholinesterase (AChE) on acetylthiocholine chloride (ATCh) is thiocholine (TCh), which helps the decomposition of MnO2 and F 530 and F 610 The fluorescence intensity is restored. TPB-DMTP@S-CDs and TPB-DMTP@S-CDs / MnO2 can provide very sensitive responses to trace amounts of OPs. 530 and F 610 Successfully identified 7.9×10 −7 μg·mL −1 The presence of OPs.

[0008] The synthesized TPB-DMTP@S-CDs and TPB-DMTP@S-CDs / MnO2 have good aqueous fluorescence stability. On the 15th day, the fluorescence of TPB-DMTP@S-CDs and TPB-DMTP@S-CDs / MnO2 530 and F 610 At the same time, TPB-DMTP@S-CDs and TPB-DMTP@S-CDs / MnO2 showed excellent tolerance to UV irradiation and extreme temperature. 530 and F 610 There were no significant changes.

[0009] Optionally, the amount of TPB-DMTP added in S23 is 5 mL 8 μg·mL −1 .

[0010] By adopting the above technical scheme, the amount of TPB-DMTP added was 5 mL 8 μg mL −1 The strongest fluorescence signals were simultaneously presented at 530 and 610 nm, and good repeatability was shown in repeated experiments.

[0011] Optionally, the amount of KMnO4 added to S23 is 1.5 mL 100 μM.

[0012] By adopting the above technical solution, as the amount of KMnO4 added increases, the amount of MnO2 generated also increases. 530 and F 610 The quenching of MnO2 increased regularly with the increase of MnO2 production, and the quenching degree was optimal when the addition amount of KMnO4 was 1.5 mL 100 μM.

[0013] In a second aspect, the present invention provides a method for using a fluorescent composite material, which adopts the following technical solution: Each sample was cut into small pieces, and then 15 mL of acetonitrile was added to exactly 10 g of the chopped sample and centrifuged at 5000 rpm for 10 minutes. The supernatant was separated and re-placed in 10 mL of 10 mM phosphate buffered saline to obtain the sample to be tested.

[0014] 1 mL of the sample to be tested was added with 10 mM phosphate buffer to reach pH = 4-12. After standing for 30 minutes, product A was obtained. 1.5 mL of product A was mixed with 0.5 mL of 50 mU acetylcholinesterase, 1 mL of 100 μM acetylthiocholine chloride, and 5 mL of 10 mM phosphate buffer and incubated at 20-60°C for 30 min to obtain an incubation solution; The incubation solution was mixed with 8 mL of 6 μg mL −1 The TPB-DMTP@S-CDs / MnO2 was reacted for 20 minutes to obtain the reaction product; The reaction product was excited by lasers with wavelengths of 410 nm and 560 nm, and the fluorescence signal of TPB-DMTP@S-CDs was captured; If the fluorescence signal intensity of the 530 nm band is lower than the first set threshold, or the fluorescence signal intensity of the 610 nm band is lower than the second set threshold, it is proved that Ops exists in the sample to be tested.

[0015] By adopting the above technical scheme, the enzyme catalysis reaction regulated by OPs was developed. The activity of AChE was inhibited by adding OPs. The enzymatic product TCh of AChE on ATCh was helpful for the decomposition of MnO2 and F 530 and F 610 The fluorescence intensity is restored. As the amount of OPs added increases, the fluorescence signal decreases. OPs species show conformational differences in the phosphate group and react with ionomers in the presence of non-isomeric addition or by attacking nucleophiles such as OH − and H +) elimination process, multi-pH pretreatment can provide a third dimension of information, because the different hydrolysis sensitivities of OPs reflect identifiable fluorescence signals, F 530 and F 610 Trends are highly synchronized. F 530 and F 610 It can provide very sensitive response to trace OPs. 530 and F 610 Successfully identified 7.9×10 −7 μg·mL −1 The presence of OPs well defines the detection limit.

[0016] At the same time, this method can coexist with metal ions 100 times higher than its own and has strong resistance to ion interference.

[0017] Optionally, after standing for 30 minutes in step (1), the pH of the product is restored to pH=8 to obtain product A.

[0018] Optionally, the incubation temperature in step (3) is 37°C.

[0019] By adopting the above technical scheme, the pH of product recovery in step (1) and the AChE catalytic effect in the incubation temperature in step (3) were optimized, and the highest F was obtained at pH = 8 and 37 °C. 530 and F 610 At this time, the catalytic effect of AChE is the best and the TCh production reaches the peak. Under the condition close to the physiological environment, the dissociation of the active group of AChE is retained, thus ensuring the binding ability between AChE and ATCh.

[0020] In a third aspect, the present invention provides a sensor using a fluorescent composite material, which adopts the following technical solution: A sensor using a fluorescent composite material comprises an integrated circuit board, a measuring cell, an LED emission module, a fluorescent receiving module and a constant temperature module.

[0021] The measuring cell is mounted on the upper surface of a flexible printed circuit (FPC), and the measuring cell is used to hold the reaction product described in the second aspect. The LED transmitting module is mounted on the integrated circuit board and in the measuring cell. The fluorescence receiving module is mounted on the integrated circuit board and in the measuring cell. The constant temperature module is mounted on the lower surface of the integrated circuit board and is installed directly below the measuring cell. The integrated circuit board is connected with the LED emission module and the constant temperature module by electrical signals, and the fluorescence receiving module is connected with the integrated circuit board by electrical signals.

[0022] By adopting the above technical solution, the constant temperature module heats the test solution in the reaction pool to 37°C and keeps it constant at this temperature through temperature control. After the product incubation reaction in the reaction pool, the LED emission module is started, and the fluorescent substance in the reaction pool is ultraviolet excited to generate emission light with intensities of 410nm and 560nm, and a weak photocurrent is formed in the fiber optic sensing photodetector module through the multimode optical fiber. The main working wavelength range of the fluorescence receiving module is 400~550 nm and 550~700nm, which is fully adapted to the dual emission peaks of TPB-DMTP@S-CDs at 530 nm and 610 nm. The two photocurrent signals from the photodiodes are amplified, converted into digital signals through the analog-to-digital conversion module, and then output to the computer. Through the synergistic effect of the two photodiodes, good dual fluorescence compatibility is achieved.

[0023] In summary, the present invention includes at least one of the following beneficial technical effects: The TPB-DMTP@S-CDs and TPB-DMTP@S-CDs / MnO2 synthesized in the present invention can provide very sensitive responses to trace amounts of OPs. 530 and F 610 Successfully identified 7.9×10 −7 μg·mL −1 The presence of OPs.

[0024] The TPB-DMTP@S-CDs and TPB-DMTP@S-CDs / MnO2 synthesized in the present invention have good aqueous phase fluorescence stability. On the 15th day, the fluorescence of TPB-DMTP@S-CDs and TPB-DMTP@S-CDs / MnO2 530 and F 610 At the same time, TPB-DMTP@S-CDs and TPB-DMTP@S-CDs / MnO2 show excellent tolerance to ultraviolet radiation and extreme temperatures, and have strong resistance to ion interference.

[0025] After the two photocurrent signals from the photodiodes of the present invention are amplified, they are converted into digital signals through an analog-to-digital conversion module and then output to a computer. Through the synergistic effect of the two photodiodes, good dual-fluorescence compatibility is achieved. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] Figure 1 This is a schematic diagram of the structure of the LED emission module of the present invention; Figure 2 It is a structural schematic diagram of the constant temperature module of the present invention; Figure 3 It is a schematic diagram of the structure of the analog-to-digital conversion module of the present invention; Figure 4 It is a schematic structural diagram of the fluorescence receiving module of the present invention; Figure 5 It is the fluorescence signal intensity diagram of 530nm and 610nm bands in natural samples; Figure 6 Fluorescence signal intensity diagram for optimizing the ratio of TPB-DMTP and S-CDs; Figure 7 0-12 μg·mL -1 Fluorescence signal intensity diagram of OPs at 530nm and 610nm; Figure 8 The aqueous phase fluorescence stability, high-power ultraviolet irradiation and extreme temperature stability of TPB-DMTP@S-CDs and TPB-DMTP@S-CDs / MnO2 are shown; Fig. 9 OPs and Mg 2+ 、Ag + , K + , Fe 3+ 、Na + 、Al 3+ Fluorescence signal intensity diagram at 530nm and 610nm bands under coexistence, A is the addition of Mg 2+ Fluorescence signal intensity of standard solution, B is the addition of Ag + Fluorescence signal intensity of standard solution, C is the fluorescence signal intensity of standard solution with K added + Fluorescence signal intensity of standard solution, D is the fluorescence signal intensity of standard solution with Fe added 3+ Fluorescence signal intensity of the standard solution, E is the fluorescence signal intensity of the standard solution with Na added + The fluorescence signal intensity of the standard solution, F is the fluorescence signal intensity of the standard solution with Al added. 3+ Fluorescence signal intensity of the standard solution.

[0027] Explanation of the reference numerals: 11, first resistor; 12, second resistor; 13, third resistor; 14, heating resistor; 15, fifth resistor; 16, sixth resistor; 17, seventh resistor; 18, eighth resistor; 19, ninth resistor; 110, tenth resistor; 111, eleventh resistor; 112, twelfth resistor; 21, first light-emitting diode; 22, second light-emitting diode; 23, third light-emitting diode; 24, fourth light-emitting diode; 25, first voltage-stabilizing diode; 26, fifth photodiode; 31, first triode; 32, second Transistor; 33, third transistor; 34, fourth transistor; 41, first operational amplifier; 42, second operational amplifier; 43, third operational amplifier; 44, fourth operational amplifier; 5, constant current diode; 61, first variable resistor; 62, second variable resistor; 7, analog-to-digital conversion chip; 8, capacitor; 91, first DC power supply; 92, second DC power supply; 93, third DC power supply; 94, fourth DC power supply; 95, fifth DC power supply; 96, sixth DC power supply; 101, first junction differential field effect transistor; 102, second junction differential field effect transistor. DETAILED DESCRIPTION

[0028] The present invention is further described in detail below with reference to the embodiments.

[0029] Example 1: This example discloses a fluorescent composite material, a method of use, and a sensor using the same, including the following steps.

[0030] A fluorescent composite material is prepared by the following steps: S1. Synthesis of TPB-DMTP: S11. At room temperature, 0.021 g of 1,3,5-tris(4-aminophenyl)benzene (TAPB) was dissolved in 9 mL of a mixture of 1,4-dioxane, butanol, and methanol, wherein the volume ratio of the 1,4-dioxane, butanol, and methanol was 4:4:1, to obtain a mixed solution A. S12, adding 0.0174 g of 2,5-dimethoxybenzaldehyde (DMTP) to the mixed solution A, and ultrasonicating for 20 minutes to obtain a mixed solution B; S13, heating the mixed solution B to 70° C. for 24 h, while adding 12 M acetic acid twice at an interval of 2 hours, with the first amount of acetic acid added being 0.1 mL and the second amount of acetic acid added being 0.9 mL, to obtain a mixed solution C; S14. Naturally cool the mixed solution C to 25° C. and centrifuge it at 5000 rpm for 15 minutes to separate the TPB-DMTP precipitate. Wash the TPB-DMTP precipitate with tetrahydrofuran and acetone, and then dry it under vacuum to obtain TPB-DMTP.

[0031] S2. Synthesis of TPB-DMTP@S-CDs: S21, heating a mixture of 4 g thiourea, 2 g citric acid and 20 mL N,N-dimethylformamide to 160° C. for 6 hours to obtain a mixed solution D; S22, the mixed solution D cooled naturally to room temperature was mixed with 40mL 50mg mL −1 100 mL of NaOH and 40 mL of 5% by volume HCl were mixed, stirred for 5 minutes, centrifuged at 16000 rpm for 15 minutes, the obtained product was washed with water, and freeze-dried at -40°C for 18 hours to obtain S-CDs; S23, 5 mL 8 μg mL −1 of TPB-DMTP and 5 mL 0.5 μg mL −1 The sulfur-doped carbon quantum (S-CDs) was stirred for 12 h to obtain TPB-DMTP@S-CDs suspension; Synthesis of S3, TPB-DMTP@S-CDs / MnO2: S31, add 1.5 mL of 100 μM potassium permanganate (KMnO4) and 1.5 mL of 1 mM 2-morpholineethanesulfonic acid (MES) to 2 mL of TPB-DMTP@S-CDs suspension to adjust the pH value of the TPB-DMTP@S-CDs suspension to pH = 6 to obtain a mixed solution E; S32. At room temperature, the mixed solution E was ultrasonically treated for about 30 minutes until a brown colloid was formed; the brown colloid was centrifuged at a rotation speed of 5000 rpm for 20 minutes to obtain a TPB-DMTP@S-CDs / MnO2 fluorescent composite material.

[0032] The usage is as follows: Each sample was cut into small pieces, and then 15 mL of acetonitrile was added to exactly 10 g of the chopped sample and centrifuged at 5000 rpm for 10 minutes. The supernatant was separated and re-placed in 10 mL of 10 mM phosphate buffered saline to obtain the sample to be tested. 1 mL 1 μg mL −1 The sample to be tested was added with 10 mM phosphate buffer to reach pH = 8. After standing for 30 minutes, product A was obtained. 1.5 mL of product A was mixed with 0.5 mL of 50 mU acetylcholinesterase, 1 mL of 100 μM acetylthiocholine chloride, and 5 mL of 10 mM phosphate buffer and incubated at 37°C for 30 min to obtain an incubation solution; The incubation solution was mixed with 8 mL of 6 μg mL −1 The TPB-DMTP@S-CDs / MnO2 was reacted for 20 minutes to obtain the reaction product; The reaction product was excited by lasers with wavelengths of 410 nm and 560 nm, and the fluorescence signal of TPB-DMTP@S-CDs was captured; If the fluorescence signal intensity of the 530 nm band is lower than the first set threshold, or the fluorescence signal intensity of the 610 nm band is lower than the second set threshold, it is proved that Ops exists in the sample to be tested.

[0033] In the embodiment of the present application, the amount of potassium permanganate (KMnO4) added is 1.5 mL 100 μM, the first set threshold is: 3289 au, and the second set threshold is: 2958 au.

[0034] The sensor adopts the following technical solutions: A sensor using a fluorescent composite material, It includes an integrated circuit board, a measuring cell, an LED emission module, a fluorescence receiving module and a constant temperature module.

[0035] The above-mentioned LED transmitting module includes a first DC power supply 91, a first resistor 11, a second resistor 12, a third resistor 13, a first operational amplifier 41, a second operational amplifier 42, a first transistor 31, a second transistor 32, a first voltage regulator diode 25, a first light-emitting diode 21, a second light-emitting diode 22, a third light-emitting diode 23 and a fourth light-emitting diode 24.

[0036] The voltage of the first DC power supply 91 is 12V.

[0037] One end of the third resistor 13 is connected to the positive electrode of the first DC power supply 91 , and the other end is connected to the negative electrode of the first Zener diode 25 . The positive electrode of the first Zener diode 25 is grounded.

[0038] The first transistor 31 and the second transistor 32 are both NPN transistors. The C end of the first transistor 31 is connected to the positive electrode of the first DC power supply 91, the E end of the first transistor 31 is connected to the positive electrode of the first light-emitting diode 21, the negative electrode of the first light-emitting diode 21 is connected to the positive electrode of the third light-emitting diode 23, the negative electrode of the third light-emitting diode 23 is connected to one end of the first resistor 11, and the other end of the first resistor 11 is grounded; the C end of the second transistor 32 is connected to the positive electrode of the first DC power supply 91, the E end of the second transistor 32 is connected to the positive electrode of the second light-emitting diode 22, the negative electrode of the second light-emitting diode 22 is connected to the positive electrode of the fourth light-emitting diode 24, the negative electrode of the fourth light-emitting diode 24 is connected to one end of the second resistor, and the other end of the second resistor 12 is grounded.

[0039] The positive input terminal of the first operational amplifier 41 is connected between the third resistor 13 and the first voltage zener diode 25, and the negative input terminal of the first operational amplifier 41 is connected between the third light-emitting diode 23 and the first resistor 11; the positive power supply of the first operational amplifier 41 is connected to the positive electrode of the first DC power supply 91, and the negative power supply of the first operational amplifier 41 is grounded; the output terminal of the first operational amplifier 41 is connected to the B terminal of the first transistor 31.

[0040] The positive input terminal of the second operational amplifier 42 is connected between the third resistor 13 and the first voltage zener diode 25, and the negative input terminal of the second operational amplifier 42 is connected between the fourth light-emitting diode 24 and the second resistor 12; the positive power supply of the second operational amplifier 42 is connected to the positive electrode of the first DC power supply 91, and the negative power supply of the second operational amplifier 42 is grounded; the output terminal of the second operational amplifier 42 is connected to the B terminal of the second transistor 32.

[0041] The above-mentioned constant temperature module includes a first DC power supply 91, a first variable resistor 61, a second variable resistor 62, a third operational amplifier 43, a heating resistor array, a fifth resistor 15, a sixth resistor 16, a third transistor 33, and a fourth transistor 34.

[0042] One end of the first variable resistor 61 is connected to the positive electrode of the first DC power supply 91 , and the other end is connected to the sixth resistor 16 . The other end of the sixth resistor 16 is grounded.

[0043] One end of the second variable resistor 62 is connected to the positive electrode of the first DC power supply 91 , and the other end is connected to the fifth resistor 15 . The other end of the fifth resistor 15 is grounded.

[0044] The positive input terminal of the third operational amplifier 43 is connected between the second variable resistor 62 and the fifth resistor 15, and the negative input terminal of the third operational amplifier 43 is connected between the first variable resistor 61 and the sixth resistor 16; the positive power supply of the third operational amplifier 43 is connected to the positive pole of the first DC power supply 91, and the negative power supply of the third operational amplifier 43 is grounded.

[0045] The third transistor 33 and the fourth transistor 34 are both NPN transistors; the output end of the third operational amplifier 43 is connected to the B end of the third transistor 33 and the B end of the fourth transistor 34, and the E end of the third transistor 33 and the E end of the fourth transistor 34 are both grounded.

[0046] The heating resistor array includes four groups of heating resistors 4, each group of heating resistors 4 includes four heating resistors 4 connected in series in sequence, one end of each group of heating resistors 4 is connected to the positive electrode of the first DC power supply 91, and the other end is connected to the C end of the third transistor 33 and the C end of the fourth transistor 34.

[0047] The above-mentioned analog-to-digital conversion module includes a second DC power supply 92, a third DC power supply 93, a seventh resistor 17, an eighth resistor 18, a ninth resistor 19, an analog-to-digital conversion chip 7, a capacitor 8, a signal input terminal and a signal output terminal.

[0048] The voltage of the second DC power supply 92 is 5V.

[0049] The voltage of the third DC power supply 93 is 3.3V.

[0050] One end of the seventh resistor 17 is connected to the positive electrode of the second DC power supply 92 , and the other end is connected to the ALERT / RDY terminal of the analog-to-digital conversion chip 7 .

[0051] One end of the eighth resistor 18 is connected to the positive electrode of the second DC power supply 92 , and the other end is connected to the SCL terminal of the analog-to-digital conversion chip 7 .

[0052] One end of the ninth resistor 19 is connected to the positive electrode of the second DC power supply 92 , and the other end is connected to the signal output end, and the signal output end is connected to the SDA end of the analog-to-digital conversion chip 7 .

[0053] One end of the capacitor 8 is connected to the positive electrode of the third DC power supply 93 , and the other end is grounded. Meanwhile, the third DC power supply 93 is connected to the VDD terminal of the analog-to-digital conversion chip 7 .

[0054] The signal input terminal is connected to the AIN0 terminal of the analog-to-digital conversion chip 7 .

[0055] The above-mentioned fluorescence receiving module includes a fourth DC power supply 94, a fifth DC power supply 95, a sixth DC power supply 96, a tenth resistor 110, an eleventh resistor 111, a twelfth resistor 112, a fourth operational amplifier 44, a fifth photodiode 26, a constant current diode 5, a first junction differential field effect transistor 101, and a second junction differential field effect transistor 102.

[0056] One end of the tenth resistor 110 is connected to the positive electrode of the fifth DC power supply 95, and the other end is connected to the source of the second junction differential field effect transistor 102. The drain of the second junction differential field effect transistor 102 is connected to one end of the constant current diode 5, and the other end of the constant current diode 5 is connected to the positive electrode of the sixth DC power supply 96. The gate of the second junction differential field effect transistor 102 is connected to the negative electrode of the fifth photodiode 26, and the positive electrode of the fifth photodiode 26 is grounded.

[0057] One end of the eleventh resistor 111 is connected to the positive electrode of the fifth DC power supply 95, and the other end is connected to the source of the first junction differential field effect transistor 101. The drain of the first junction differential field effect transistor 101 is connected to one end of the constant current diode 5, and the gate of the first junction differential field effect transistor 101 is grounded.

[0058] The positive input terminal of the fourth operational amplifier 44 is connected between the tenth resistor 110 and the source of the second junction differential field effect transistor 102, and the negative input terminal of the third operational amplifier 43 is connected between the eleventh resistor 111 and the source of the first junction differential field effect transistor 101; the positive power supply of the fourth operational amplifier 44 is connected to the positive electrode of the fourth DC power supply 94, and the negative power supply of the fourth operational amplifier 44 is grounded; the output terminal of the fourth operational amplifier 44 is connected to one end of the twelfth resistor 112, and the other end of the twelfth resistor 112 is connected between the gate of the second junction differential field effect transistor 102 and the negative electrode of the fifth photodiode 26.

[0059] The measuring pool is mounted on the upper surface of the FPC, and the measuring pool is used to hold the reaction product in the above-mentioned method of use. The LED transmitting module is mounted on the integrated circuit board and in the measuring pool. The fluorescence receiving module is mounted on the integrated circuit board and in the measuring pool. The constant temperature module is mounted on the lower surface of the integrated circuit board, and the installation position is directly below the measuring pool. The integrated circuit board is connected with the LED emission module and the constant temperature module by electrical signals, and the fluorescence receiving module is connected with the integrated circuit board by electrical signals.

[0060] In step (3), 1.5 mL of product A is mixed with 0.5 mL of 50 mU acetylcholinesterase, 1 mL of 100 μM acetylthiocholine chloride, and 5 mL of 10 mM phosphate buffer, and then placed in a measuring cell. The solution in the measuring cell is heated to 37° C. by a constant temperature module for incubation to obtain an incubation solution. In step (4), 8 mL of 6 μg mL −1 TPB-DMTP@S-CDs / MnO2 was added into the reaction cell and continued to react in the measurement cell for 20 minutes to obtain the reaction product; In step (5), the LED emission module is used to emit lasers with wavelengths of 410 nm and 560 nm to irradiate the reaction products in the reaction pool, and the fluorescence receiving module is used to capture the fluorescence signal.

[0061] Example 1 and Comparative Example Figure 5 It can be seen from the data that OPs contained in natural samples were successfully separated. The present invention is not only effective for laboratory samples, but can also distinguish OPs in natural samples well.

[0062] Comparative Example: This comparative example discloses a fluorescent composite material, a method of using the same, and a sensor using the same, including the following steps.

[0063] The usage is as follows: (1) Add 10 mM phosphate buffer to 1 mL of deionized water to reach pH = 8. After standing for 30 minutes, product A is obtained. The rest is exactly the same as in Example 1.

[0064] Example 2: This example discloses a fluorescent composite material, a method of using the same, and a sensor using the same, including the following steps.

[0065] The preparation method is as follows, S23, 5 mL 4 μg mL −1 of TPB-DMTP and 5 mL 0.5 μg mL −1 The sulfur-doped carbon quantum (S-CDs) was stirred for 12 h to obtain TPB-DMTP@S-CDs suspension; The rest is exactly the same as in Example 1.

[0066] Example 3: This example discloses a fluorescent composite material, a method of use, and a sensor using the same, including the following steps.

[0067] The preparation method is as follows, S23, 5 mL 6μg mL −1 of TPB-DMTP and 5 mL 0.5 μg mL −1 The sulfur-doped carbon quantum (S-CDs) was stirred for 12 h to obtain TPB-DMTP@S-CDs suspension; The rest is exactly the same as in Example 1.

[0068] Embodiment 4: This embodiment discloses a fluorescent composite material, a method of using the same, and a sensor using the same, including the following steps.

[0069] The preparation method is as follows, S23, 5 mL 10 μg mL −1 of TPB-DMTP and 5 mL 0.5 μg mL −1 The sulfur-doped carbon quantum (S-CDs) was stirred for 12 h to obtain TPB-DMTP@S-CDs suspension; The rest is exactly the same as in Example 1.

[0070] Example 5: This example discloses a fluorescent composite material, a method of using the same, and a sensor using the same, including the following steps.

[0071] The preparation method is as follows, S23, 5 mL 12 μg mL −1 of TPB-DMTP and 5 mL 0.5 μg mL −1 The sulfur-doped carbon quantum (S-CDs) was stirred for 12 h to obtain TPB-DMTP@S-CDs suspension; The rest is exactly the same as in Example 1.

[0072] Example 1 and Example 2, Example 3, Example 4, Example 5 from Figure 6 Data comparison shows that the amount of TPB-DMTP added in Example 1 is 5 mL 8 μg·mL −1 The strongest fluorescence signals were simultaneously presented at 530 and 610 nm, and good repeatability was shown in repeated experiments.

[0073] Example 6: This example discloses a fluorescent composite material, a method of use, and a sensor using the same, including the following steps.

[0074] The usage is as follows: Chlorpyrifos (CPF) was dissolved in deionized water to obtain a sample to be tested.

[0075] 1 mL 7.9×10 −7 μg·mL −1 The sample to be tested was added with 10 mM phosphate buffer to reach pH = 8. After standing for 30 minutes, product A was obtained. The rest is exactly the same as in Example 1.

[0076] Example 7: This example discloses a fluorescent composite material, a method of using the same, and a sensor using the same, including the following steps.

[0077] The usage is as follows: Chlorpyrifos (CPF) was dissolved in deionized water to obtain a sample to be tested.

[0078] 1 mL of 1×10 −6 μg·mL −1 The sample to be tested was added with 10 mM phosphate buffer to reach pH = 8. After standing for 30 minutes, product A was obtained. The rest is exactly the same as in Example 1.

[0079] Embodiment 8: This embodiment discloses a fluorescent composite material, a method of using the same, and a sensor using the same, including the following steps.

[0080] The usage is as follows: Chlorpyrifos (CPF) was dissolved in deionized water to obtain a sample to be tested.

[0081] 1 mL of 1×10 −5 μg·mL −1 The sample to be tested was added with 10 mM phosphate buffer to reach pH = 8. After standing for 30 minutes, product A was obtained. The rest is exactly the same as in Example 1.

[0082] Example 9: This example discloses a fluorescent composite material, a method of use, and a sensor using the same, including the following steps.

[0083] The usage is as follows: Chlorpyrifos (CPF) was dissolved in deionized water to obtain a sample to be tested.

[0084] 1 mL of 1×10 −4 μg·mL −1 The sample to be tested was added with 10 mM phosphate buffer to reach pH = 8. After standing for 30 minutes, product A was obtained. The rest is exactly the same as in Example 1.

[0085] Embodiment 10: This embodiment discloses a fluorescent composite material, a method of using the same, and a sensor using the same, including the following steps.

[0086] The usage is as follows: Chlorpyrifos (CPF) was dissolved in deionized water to obtain a sample to be tested.

[0087] 1 mL of 1×10 −3 μg·mL −1 The sample to be tested was added with 10 mM phosphate buffer to reach pH = 8. After standing for 30 minutes, product A was obtained. The rest is exactly the same as in Example 1.

[0088] Embodiment 11: This embodiment discloses a fluorescent composite material, a method of using the same, and a sensor using the same, including the following steps.

[0089] The usage is as follows: Chlorpyrifos (CPF) was dissolved in deionized water to obtain a sample to be tested.

[0090] 1 mL of 1×10 −2 μg·mL −1 The sample to be tested was added with 10 mM phosphate buffer to reach pH = 8. After standing for 30 minutes, product A was obtained. The rest is exactly the same as in Example 1.

[0091] Example 12: This example discloses a fluorescent composite material, a method of use, and a sensor using the same, including the following steps.

[0092] The usage is as follows: Chlorpyrifos (CPF) was dissolved in deionized water to obtain a sample to be tested.

[0093] 1 mL 1 μg mL −1 The sample to be tested was added with 10 mM phosphate buffer to reach pH = 8. After standing for 30 minutes, product A was obtained. The rest is exactly the same as in Example 1.

[0094] Example 13: This example discloses a fluorescent composite material, a method of use, and a sensor using the same, including the following steps.

[0095] The usage is as follows: (1) Dissolve chlorpyrifos (CPF) in deionized water to obtain a sample to be tested.

[0096] (2) 1 mL 12 μg mL −1 The sample to be tested was added with 10 mM phosphate buffer to reach pH = 8. After standing for 30 minutes, product A was obtained. The rest is exactly the same as in Example 1.

[0097] Example 1 and Example 6, Example 7, Example 8, Example 9, Example 10, Example 11, Example 12, Example 13, Comparative Example Figure 7 Data comparison shows that F 530 and F 610 It can provide very sensitive response to trace OPs. 530 and F 610 Successfully identified 7.9×10 −7 μg·mL −1 The presence of OPs well defines the detection limit.

[0098] Example 14: This example discloses a fluorescent composite material including the following steps.

[0099] A fluorescent composite material is prepared by the following steps: S1. Synthesis of TPB-DMTP: S11. At room temperature, 0.021 g of 1,3,5-tris(4-aminophenyl)benzene (TAPB) was dissolved in 9 mL of a mixture of 1,4-dioxane, butanol, and methanol, wherein the volume ratio of the 1,4-dioxane, butanol, and methanol was 4:4:1, to obtain a mixed solution A. S12, adding 0.0174 g of 2,5-dimethoxybenzaldehyde (DMTP) to the mixed solution A, and ultrasonicating for 20 minutes to obtain a mixed solution B; S13, heating the mixed solution B to 70° C. for 24 h, while adding 12 M acetic acid twice at an interval of 2 hours, with the first amount of acetic acid added being 0.1 mL and the second amount of acetic acid added being 0.9 mL, to obtain a mixed solution C; S14. Naturally cool the mixed solution C to 25° C. and centrifuge it at 5000 rpm for 15 minutes to separate the TPB-DMTP precipitate. Wash the TPB-DMTP precipitate with tetrahydrofuran and acetone, and then dry it under vacuum to obtain TPB-DMTP.

[0100] S2. Synthesis of TPB-DMTP@S-CDs: S21, heating a mixture of 4 g thiourea, 2 g citric acid and 20 mL N,N-dimethylformamide to 160° C. for 6 hours to obtain a mixed solution D; S22, the mixed solution D cooled naturally to room temperature was mixed with 40mL 50mg mL −1 100 mL of NaOH and 40 mL of 5% by volume HCl were mixed, stirred for 5 minutes, centrifuged at 16000 rpm for 15 minutes, the obtained product was washed with water, and freeze-dried at -40°C for 18 hours to obtain S-CDs; S23, 5 mL 8 μg mL −1 of TPB-DMTP and 5 mL 0.5 μg mL −1 The sulfur-doped carbon quantum (S-CDs) was stirred for 12 h to obtain TPB-DMTP@S-CDs suspension; Synthesis of S3, TPB-DMTP@S-CDs / MnO2: S31, add 1.5 mL of 100 μM potassium permanganate (KMnO4) and 1.5 mL of 1 mM 2-morpholineethanesulfonic acid (MES) to 2 mL of TPB-DMTP@S-CDs suspension to adjust the pH value of the TPB-DMTP@S-CDs suspension to pH = 6 to obtain a mixed solution E; S32. At room temperature, the mixed solution E was ultrasonically treated for about 30 minutes until a brown colloid was formed; the brown colloid was centrifuged at a rotation speed of 5000 rpm for 20 minutes to obtain a TPB-DMTP@S-CDs / MnO2 fluorescent composite material.

[0101] S4. Place the above TPB-DMTP@S-CDs and TPB-DMTP@S-CDs / MnO2 for 15 days and detect F 530 and F 610 .

[0102] Example 15: This example discloses a fluorescent composite material including the following steps.

[0103] S4. The TPB-DMTP@S-CDs and TPB-DMTP@S-CDs / MnO2 were irradiated with high-power ultraviolet light at 365 nm and 60 W for 3 h at room temperature. 530 and F 610 .

[0104] The rest is exactly the same as Example 14.

[0105] Example 16: This example discloses a fluorescent composite material including the following steps.

[0106] S4. Soak the above TPB-DMTP@S-CDs and TPB-DMTP@S-CDs / MnO2 at 85°C for 3 hours and detect F 530 and F 610 .

[0107] The rest is exactly the same as Example 14.

[0108] Example 14, Example 15 and Example 16 Figure 8 It can be seen that TPB-DMTP@S-CDs and TPB-DMTP@S-CDs / MnO2 have good aqueous phase fluorescence stability. On the 15th day, the fluorescence of TPB-DMTP@S-CDs and TPB-DMTP@S-CDs / MnO2 530 and F 610 Stay well.

[0109] Meanwhile, TPB-DMTP@S-CDs and TPB-DMTP@S-CDs / MnO2 exhibited excellent tolerance to the aforementioned high-power UV irradiation and extreme temperature. 530 and F 610 There were no significant changes.

[0110] Example 17: This example discloses a fluorescent composite material, a method of use, and a sensor using the same, including the following steps.

[0111] The usage is as follows: (4) Mix the incubation solution with 8 mL of 6 μg mL −1 The TPB-DMTP@S-CDs / MnO2 was reacted for 20 min, and 100 μg·mL -1 Mg 2+ Standard solution to obtain the reaction product; The rest is exactly the same as in Example 1.

[0112] Example 18: This example discloses a fluorescent composite material, a method of use, and a sensor using the same, including the following steps.

[0113] The usage is as follows: (4) Mix the incubation solution with 8 mL of 6 μg mL −1 The TPB-DMTP@S-CDs / MnO2 was reacted for 20 min, and 100 μg·mL -1 Ag + Standard solution to obtain the reaction product; The rest is exactly the same as in Example 1.

[0114] Example 19: This example discloses a fluorescent composite material, a method of use, and a sensor using the same, including the following steps.

[0115] The usage is as follows: (4) Mix the incubation solution with 8 mL of 6 μg mL −1 The TPB-DMTP@S-CDs / MnO2 was reacted for 20 min, and 100 μg·mL -1 K + Standard solution to obtain the reaction product; The rest is exactly the same as in Example 1.

[0116] Example 20: This example discloses a fluorescent composite material, a method of use, and a sensor using the same, including the following steps.

[0117] The usage is as follows: (4) Mix the incubation solution with 8 mL of 6 μg mL −1 The TPB-DMTP@S-CDs / MnO2 was reacted for 20 min, and 100 μg·mL -1 Fe 3+ Standard solution to obtain the reaction product; The rest is exactly the same as in Example 1.

[0118] Example 21: This example discloses a fluorescent composite material, a method of use, and a sensor using the same, including the following steps.

[0119] The usage is as follows: (4) Mix the incubation solution with 8 mL of 6 μg mL −1 The TPB-DMTP@S-CDs / MnO2 was reacted for 20 min, and 100 μg·mL -1 Na + Standard solution to obtain the reaction product; The rest is exactly the same as in Example 1.

[0120] Example 22: This example discloses a fluorescent composite material, a method of use, and a sensor using the same, including the following steps.

[0121] The usage is as follows: (4) Mix the incubation solution with 8 mL of 6 μg mL −1 The TPB-DMTP@S-CDs / MnO2 was reacted for 20 min, and 100 μg·mL -1 Al 3+ Standard solution to obtain the reaction product; The rest is exactly the same as in Example 1.

[0122] Example 17, Example 18, Example 19, Example 20, Example 21, Example 22 from Fig. 9 and Figure 4 It can be seen from the comparison of the presence of OP in the solution that this method can coexist with metal ions 100 times higher than that of OP, and has a strong ability to resist ion interference. 2+ 、Ag + , K + , Fe 3+ 、Na + 、Al 3+ After emergence, OPs can still be identified.

[0123] The above are all preferred embodiments of the present invention, and are not intended to limit the protection scope of the present invention. Therefore, any equivalent changes made based on the structure, shape, and principle of the present invention should be included in the protection scope of the present invention.

Claims

1. A fluorescent composite material, characterized in that: Made using the following steps: S1. Synthesis of TPB-DMTP: S11. At room temperature, 0.021 g of 1,3,5-tris(4-aminophenyl)benzene was dissolved in 9 mL of a mixture of 1,4-dioxane, butanol, and methanol, wherein the volume ratio of the 1,4-dioxane, butanol, and methanol was 4:4:1, to obtain a mixed solution A. S12, adding 0.0174 g of 2,5-dimethoxybenzaldehyde to the mixed solution A, and ultrasonicating for 20 minutes to obtain a mixed solution B; S13, heating the mixed solution B to 70° C. for 24 h, while adding 12 M acetic acid twice at an interval of 2 hours, with the first amount of acetic acid added being 0.1 mL and the second amount of acetic acid added being 0.9 mL, to obtain a mixed solution C; S14, naturally cooling the mixed solution C to 25° C. and centrifuging at a rotation speed of 5000 rpm for 15 minutes to separate the TPB-DMTP precipitate, washing the TPB-DMTP precipitate with tetrahydrofuran and acetone, and then drying under vacuum to obtain TPB-DMTP; S2. Synthesis of TPB-DMTP@S-CDs: S21, heating a mixture of 4 g thiourea, 2 g citric acid and 20 mL N,N-dimethylformamide to 160° C. for 6 hours to obtain a mixed solution D; S22, the mixed solution D cooled naturally to room temperature was mixed with 40mL 50mg mL −1 100 mL of sodium hydroxide and 40 mL of 5% hydrochloric acid by volume were mixed, stirred for 5 minutes, centrifuged at 16000 rpm for 15 minutes, the obtained product was washed with water, and freeze-dried at -40°C for 18 hours to obtain S-CDs; S23, 5 mL 4-12 μg mL −1 of TPB-DMTP and 5 mL 0.5 μg mL −1 The S-CDs were stirred for 12 h to obtain TPB-DMTP@S-CDs suspension; Synthesis of S3, TPB-DMTP@S-CDs / MnO2: S31, adding 1.5 mL of 1-100 μM potassium permanganate and 1.5 mL of 1 mM 2-morpholineethanesulfonic acid to 2 mL of TPB-DMTP@S-CDs suspension to adjust the pH value of the TPB-DMTP@S-CDs suspension to pH = 6 to obtain a mixed solution E; S32. At room temperature, the mixed solution E was ultrasonically treated for about 30 minutes until a brown colloid was formed; the brown colloid was centrifuged at a rotation speed of 5000 rpm for 20 minutes to obtain a TPB-DMTP@S-CDs / MnO2 fluorescent composite material.

2. A fluorescent composite material according to claim 1, characterized in that: The amount of TPB-DMTP added in S23 is 5 mL 8 μg·mL −1 .

3. A fluorescent composite material according to claim 1, characterized in that: The amount of KMnO4 added to the S23 is 1.5 mL 100 μM.

4. A method for using a fluorescent composite material, using the fluorescent composite material according to any one of claims 1 to 3, characterized in that: The following technical solutions are adopted: Each sample was cut into small pieces, and then 15 mL of acetonitrile was added to exactly 10 g of the chopped sample and centrifuged at 5000 rpm for 10 minutes. The supernatant was separated and re-placed in 10 mL of 10 mM phosphate buffered saline to obtain the sample to be tested; Add 10 mM phosphate buffer to 1 mL of the sample to be tested to reach pH = 4-12, and let it stand for 30 minutes to obtain product A; 1.5 mL of product A was mixed with 0.5 mL of 50 mU acetylcholinesterase, 1 mL of 100 μM acetylthiocholine chloride, and 5 mL of 10 mM phosphate buffer and incubated at 20-60°C for 30 min to obtain an incubation solution; The incubation solution was mixed with 8 mL of 6 μg mL −1 The TPB-DMTP@S-CDs / MnO2 was reacted for 20 minutes to obtain the reaction product; The reaction product was excited by lasers with wavelengths of 410 nm and 560 nm, and the fluorescence signal of TPB-DMTP@S-CDs was captured; If the intensity of the fluorescence signal in the 530 nm band is lower than the first set threshold, or the intensity of the fluorescence signal in the 610 nm band is lower than the second set threshold, it is proved that Ops exists in the sample to be tested.

5. The method for using the fluorescent composite material according to claim 4, characterized in that: After the step (1) was allowed to stand for 30 minutes, the pH of the product was restored to pH=8 to obtain product A.

6. The method for using the fluorescent composite material according to claim 4, characterized in that: The incubation temperature in step (3) is 37°C.

7. A sensor, which uses the fluorescent composite material according to any one of claims 1 to 3 to implement the method for using the fluorescent composite material according to any one of claims 4 to 6, characterized in that: It includes an integrated circuit board, a measuring cell, an LED transmitting module, a fluorescence receiving module and a constant temperature module; The measuring cell is mounted on the upper surface of the flexible circuit board, and the measuring cell is used to hold the reaction product described in any one of claims 4 to 6. The LED transmitting module is mounted on the integrated circuit board and in the measuring cell. The fluorescence receiving module is mounted on the integrated circuit board and in the measuring cell. The constant temperature module is mounted on the lower surface of the integrated circuit board and is installed directly below the measuring cell. The integrated circuit board is connected with the LED emission module and the constant temperature module by electrical signals, and the fluorescence receiving module is connected with the integrated circuit board by electrical signals.

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