Preparation method and application of electrochemiluminescence sensor based on inverse opal photonic crystal

Abstract

The application belongs to the technical field of electrochemiluminescence detection, and particularly relates to a preparation method and application of an electrochemiluminescence sensor based on inverse opal photonic crystals. The main component materials of the sensor are polystyrene microspheres, a luminophore PTCA-TCPP and a catalyst LaCoO3. The polystyrene microspheres are converted into an inverse opal photonic crystal PIOPCs structure in the preparation process of the sensor, so that the light intensity is improved, and meanwhile, the excess polystyrene realizes stable signal output of electrochemiluminescence by bonding the PTCA-TCPP and the LaCoO3. The detection method is a traditional three-electrode system composed of a LaCoO3 / PTCA-TCPP / PIOPCs / GCE modified electrode, an Ag / AgCl electrode and a Pt electrode. The preparation method of the sensor in the application is simple, the stability is good, the sensitivity for AB-PINACA detection is high, and the linear range is wide.

Description

Technical Field

[0001] The present invention relates to the field of electrochemiluminescence detection, and more particularly to a method for preparing and applying an electrochemiluminescence sensor based on inverse opal photonic crystals. More specifically, it relates to the conversion of polystyrene (PS) microspheres into inverse opal photonic crystals, an electrochemiluminescence sensor for detecting the synthetic cannabinoid AB-PINACA, and its preparation and application. Background Art

[0002] Synthetic cannabinoids (SCs) are among the most abused new psychoactive substances worldwide. Initially introduced as pharmaceuticals, they have since been abused due to their stronger effects than natural cannabinoids. A new synthetic cannabinoid can be created by simply modifying the original structure. In recent years, numerous serious poisoning and deaths caused by overdoses of synthetic cannabinoids have attracted the attention of various countries, which have taken corresponding measures to strengthen drug control. Given that synthetic cannabinoids can produce anesthetic and stimulant effects, e-cigarette oils have become an ideal place to hide synthetic cannabinoids, making it necessary to detect synthetic cannabinoids in e-cigarettes.

[0003] Currently, the main methods for detecting synthetic cannabinoids include chromatography-mass spectrometry and electrochemiluminescence (ECL). ECL, with its simple procedure, high sensitivity, and wide detection range, has become an excellent method for detecting SCs. ECL is a chemiluminescence phenomenon controlled by an electrochemical reaction. Redox reactions between substances on the electrode surface lead to the generation of an excited state, which then emits light during the return to the ground state. Compared to simple electrochemical and chemiluminescence methods, this method offers significant advantages, such as lack of background interference and high sensitivity. Photonic crystals (PCs) are crystalline materials with a periodic dielectric structure. PCs of varying lattices and sizes can modulate electromagnetic waves of varying wavelengths. Their unique "photonic band gap" structure blocks photons of corresponding wavelengths, thereby enabling wavelength control. Due to its excellent optical modulation of signal intensity, PCs are considered promising materials for amplifying spontaneous emission and controlling light propagation. Currently, there are few reports on the use of three-electrode systems for detecting AB-PINACA using ECL. Summary of the Invention

[0004] The present invention aims to address the shortcomings of existing techniques for detecting the synthetic cannabinoid AB-PINACA by providing an electrochemiluminescence (ECL) sensor based on inverse opal photonic crystals for detecting the synthetic cannabinoid AB-PINACA. By utilizing the electrostatic interactions between these substances, the present invention co-modifies polystyrene (PS) microspheres, PTCA-TCPP, and LaCoO3 onto the surface of a glassy carbon electrode, resulting in a LaCoO3 / PTCA-TCPP / PIOPCs / GCE ECL sensor. This significantly improves the sensitivity and stability of the ECL.

[0005] In order to achieve the purpose of the present invention, the technical solution adopted is: an electrochemiluminescence sensor based on inverse opal photonic crystals, including a LaCoO3 / PTCA-TCPP / PIOPCs composite material modified onto the surface of a glassy carbon electrode; wherein polystyrene inverse opals (PIOPCs) are formed by PS microspheres under the action of dimethylformamide (DMF); the LaCoO3 / PTCA-TCPP composite material is formed by LaCoO3 and PTCA-TCPP through electrostatic interaction.

[0006] The present invention also provides a preparation method of the above-mentioned electrochemiluminescence sensor based on inverse opal photonic crystals: PTCA-TCPP and LaCoO3 are dispersed in DMF respectively, and ultrasonically dispersed to obtain a dispersion of PTCA-TCPP and LaCoO3; PS microspheres are dispersed in deionized water, and ultrasonically dispersed to obtain a dispersion of PS microspheres; PS microspheres, luminophore PTCA-TCPP, and LaCoO3 dispersion are sequentially drop-coated on the surface of a clean glassy carbon electrode, so that the PS microspheres are converted into PIOPCs under the action of DMF in the PTCA-TCPP and LaCoO3 dispersions, and the mixture is naturally dried to obtain a glassy carbon electrode modified with a composite material LaCoO3 / PTCA-TCPP / PIOPCs.

[0007] Preparation of PS microspheres: Sodium lauryl sulfate, styrene, and water are added to a reactor and nitrogen is introduced to fully remove dissolved oxygen to obtain a mixed solution. The mixed solution is fully emulsified at 58-62°C, then heated to 73-77°C. A 5% K2S2O8 solution is added and the reaction is continued for 10-13 hours to obtain a white milky product. The product is washed, gradient centrifuged, and vacuum dried to obtain PS microspheres with uniform particle size. The mass volume ratio of sodium lauryl sulfate:styrene:water is 1 g:500 mL:2000 mL. The K2S2O8 solution acts as a seed crystal, and the volume of the added K2S2O8 solution is determined by the volume of styrene, with a volume ratio of styrene:5% K2S2O8 of 2 to 2.5:1. The resulting PS microspheres have a particle size of 475-525 nm.

[0008] Preparation of PTCA-TCPP: ZrCl4 and 3,4,9,10-perylenetetracarboxylic acid (PTCA) are dissolved in DMF under ultrasonic conditions and heated to 80-90°C to complete the reaction to form solution a; meso-tetra(4-carboxyphenyl)porphine (TCPP) and benzoic acid are dissolved in DMF to form solution b; solution b is added to solution a, mixed, and reacted at 115-125°C until complete; the mixture is cooled to room temperature, washed, and vacuum-dried to obtain PTCA-TCPP solid particles; wherein the mass ratio of ZrCl4 to PTCA is 10:35; and the mass ratio of TCPP to benzoic acid is 10:500.

[0009] LaCoO3 was prepared by adding 1.6 g of La(NO3)3·6H2O and 0.9 g of Co(OAc)2·6H2O to a mixture of urea, nitric acid, citric acid, and deionized water. The solution was then heated to 80°C and stirred continuously with a magnetic stirrer until a gel formed. The gel was dried at 170°C for 12 hours and finally calcined at 600°C for 6 hours to crystallize. The resulting black powder, LaCoO3, was ground into powder. The mass ratio of urea:nitric acid:citric acid was 0.9:2.9 g:3.1 g, and the molar ratio of La(NO3)3·6H2O to Co(OAc)2·6H2O was 2-3:1.

[0010] Furthermore, the concentration of the aqueous dispersion of PS microspheres is 0.1-0.5 mg / mL, preferably 0.5 mg / mL; the drop coating volume is 70 μL / cm 2 ;

[0011] Furthermore, the modification mass ratio of PTCA-TCPP to LaCoO3 is 1:1; wherein the concentration of PTCA-TCPP in DMF dispersion is 0.5-1 mg / mL, preferably 1 mg / mL; the drop coating amount is 28 μL / cm 2 The concentration of LaCoO3 DMF dispersion is 0.5-1mg / mL, preferably 1mg / mL; the drop coating amount is 28μL / cm 2 .

[0012] Furthermore, to enhance the specificity of the sensor, the carboxyl groups on the surface of the glassy carbon electrode modified with the LaCoO3 / PTCA-TCPP / PIOPCs composite were activated with an aqueous solution of EDC / NHS. The mass ratio of EDC to NHS in the aqueous solution was 4:1, and the modification amount was 56 μL / cm 2 .

[0013] The cleaning method of the clean glassy carbon electrode of the present invention comprises: polishing the glassy carbon electrode, ultrasonically cleaning it with nitric acid solution, ethanol solution and ultrapure water in sequence, and drying it at room temperature.

[0014] The present invention discloses an application of an electrochemiluminescence sensor based on an inverse opal photonic crystal in detecting the synthetic cannabinoid AB-PINACA. Specifically, a three-electrode system is formed by using the electrochemiluminescence sensor (LaCoO3 / PTCA-TCPP / PIOPCs / GCE) as a working electrode, Ag / AgCl as a reference electrode, and a platinum wire electrode as a counter electrode. AB-PINACA in a sample is incubated and fixed to the surface of the sensor, and the synthetic cannabinoid AB-PINACA is detected by changes in the generated electrochemiluminescence signal.

[0015] Furthermore, the sample dosage is 3 μL and the incubation time is 20-30 min.

[0016] Furthermore, using K2S2O8 in PBS buffer solution as the electrolyte, cyclic voltammetry was performed in the electrochemical window range of -1.8 to 0 V, with a photomultiplier tube high voltage of 800 V and a scan rate of 0.1 V / s to detect the luminescence intensity, and the concentration of AB-PINACA in the sample was calculated according to the linear regression equation.

[0017] Furthermore, the PBS buffer solution of K2S2O8 is a PBS buffer solution containing 0.05 mol / L K2S2O8 prepared with 0.1 mol / L PBS buffer solution with a pH of 7.5.

[0018] Further, the specific steps are:

[0019] Step 1, preparation of PBS buffer solution containing K2S2O8:

[0020] Prepare a PBS buffer solution containing 0.05 mol / L K2S2O8 using a 0.1 mol / L PBS buffer solution at pH 7.5;

[0021] Step 2, preparation of AB-PINACA standard solutions of different concentrations: -3 The AB-PINACA mother solution of 1.0×10-1.0 was diluted with anhydrous ethanol to obtain a series of AB-PINACA standard solutions with different concentrations. -12 ~1.0×10 -3 g / L;

[0022] Step 3, drawing of standard curve:

[0023] Equal amounts of AB-PINACA standard solutions of different concentrations prepared according to step 2 were modified on the electrochemiluminescence sensor and reacted for the same time to allow the electrochemiluminescence sensor to bind to AB-PINACA. A three-electrode system was then formed using a LaCoO3 / PTCA-TCPP / PIOPCs / GCE modified electrode as a working electrode, an Ag / AgCl reference electrode, and a platinum electrode as a counter electrode. The PBS buffer solution containing K2S2O8 in step 1 was used as an electrolyte. Cyclic voltammetry was performed within the electrochemical window range of -1.8 to 0 V with a photomultiplier tube high voltage of 800 V and a scan rate of 0.1 V / s. The luminescence intensity-time curve was recorded, and a linear relationship between the luminescence intensity difference (ΔECL) before and after the electrochemiluminescence sensor bound to AB-PINACA and the logarithm of the AB-PINACA concentration in the AB-PINACA standard solution was established to obtain a corresponding linear regression equation.

[0024] Step 4, detection of AB-PINACA in samples

[0025] The sample was first centrifuged to remove insoluble impurities and then further filtered using vacuum filtration. The resulting sample solution was modified on the surface of an electrochemiluminescence sensor according to step 3 and reacted for the same time, allowing the electrochemiluminescence sensor to bind to AB-PINACA. The AB-PINACA / LaCoO3 / PTCA-TCPP / PIOPCs / GCE working electrode was then used to measure the luminescence intensity using the method in step 3. The concentration of AB-PINACA in the sample was then calculated using a linear regression equation.

[0026] Compared with the prior art, the present invention has achieved the following beneficial effects:

[0027] Polystyrene (PS) microspheres are generally considered to be a stable optical material in the visible to near-infrared spectral range because they generally do not absorb light with wavelengths exceeding 300nm. By utilizing the swelling properties of PS, PSPCs can be converted into polystyrene inverse opals (PIOPCs). While retaining the properties of spontaneous emission amplification, the excess polystyrene acts as a binder to fix the material to the inverse opal surface, improving the stability of the luminescent material.

[0028] During the electrode modification process, PS microspheres, under the action of DMF, are converted into PIOPCs with a specific pore size. Their unique photonic bandgap structure reflects light of the same wavelength as the luminophore, enhancing the spontaneous emission of the ECL signal. In the presence of DMF, some of the polystyrene immobilizes LaCoO3 / PTCA-TCPP on the glassy carbon electrode, achieving stable signal output from the sensor. LaCoO3 significantly catalyzes the decomposition of the co-reactant K2S2O8, enhancing the ECL signal. To enhance the sensor's specificity, the carboxyl groups are activated with EDC / NHS before adding the analyte. Upon addition of the analyte AB-PINACA, the ECL signal of the LaCoO3 / PTCA-TCPP / PIOPCs / GCE electrochemiluminescence sensor exhibits a significant quenching phenomenon, demonstrating sensitive detection of AB-PINACA. The addition of other interfering substances also confirmed the sensor's good specificity.

[0029] This invention designs an electrochemiluminescence (ECL) sensor (LaCoO3 / PTCA-TCPP / PIOPCs / GCE) based on a composite material of polystyrene inverse opal photonic crystals (PIOPCs), an organic macrocyclic luminophore (PTCA-TCPP), and an oxide perovskite (LaCoO3). The materials are bonded via electrostatic interactions, resulting in high and stable ECL performance. PIOPCs are formed by PS microspheres in the presence of DMF, enhancing the spontaneous emission of the ECL signal. Polystyrene immobilizes LaCoO3 and PTCA-TCPP on the surface of a glassy carbon electrode, achieving stable ECL signal output. EDC / NHS enhances the specificity of the ECL sensor by activating carboxyl groups. Through the quenching mechanism of the ECL signal intensity of this system by AB-PINACA, sensitive detection of AB-PINACA is achieved. This sensing platform can specifically identify the target AB-PINACA with high selectivity. The present invention's detection of AB-PINACA is simple, with good selectivity, high sensitivity, and a wide detection range. This invention is of great significance for promoting the practical application of sensors in electronic cigarette safety testing. BRIEF DESCRIPTION OF THE DRAWINGS

[0030] Figure 1 The figure is a brief flow chart of the preparation of the electrochemiluminescence sensor and the detection of AB-PINACA in the present invention;

[0031] Figure 2 The ECL response graphs of the electrochemiluminescence sensor constructed in Example 1 after binding to different concentrations of AB-PINACA, where the concentrations of AB-PINACA from a to j are as follows: (a) 1.0×10 -12 g / L; (b) 1.0×10 -11g / L; (c) 1.0×10 -10 g / L; (d)1.0×10 -9 g / L; (e) 1.0×10 -8 g / L; (f) 1.0×10 -7 g / L; (g)1.0×10 -6 g / L; (h)1.0×10 -5 g / L; (i) 1.0×10 -4 g / L; (j) 1.0×10 -3 g / L;

[0032] Figure 3 The standard curve is the difference in luminescence intensity before and after adding AB-PINACA (ΔECL) and the logarithm of AB-PINACA concentration in Example 1;

[0033] Figure 4 are the scanning electron micrographs of PS microspheres (A), PTCA-TCPP (B), LaCoO3 (C), LaCoO3 / PTCA-TCPP / PIOPCs (D), PIOPCs (E), and LaCoO3 / PTCA-TCPP / PS (F);

[0034] Figure 5 are the ECL-potential curves of LaCoO3 / PTCA-TCPP / GCE (a) and LaCoO3 / PTCA-TCPP / PIOPCs / GCE (b);

[0035] Figure 6 are the ECL-time curves of LaCoO3 / PTCA-TCPP / GCE (a) and LaCoO3 / PTCA-TCPP / PIOPCs / GCE (b);

[0036] Figure 7 Zeta potential of GCE (a), PS microspheres (b), PTCA-TCPP (c), LaCoO3 (d), and AB-PINACA (e). DETAILED DESCRIPTION

[0037] The present invention is not limited to the following specific embodiments. Based on the disclosure of the present invention, a person skilled in the art may adopt a variety of other specific embodiments to implement the present invention. Any simple changes or modifications made to the design structure and concept of the present invention fall within the scope of protection of the present invention. It should be noted that the embodiments and features of the embodiments of the present invention may be combined with each other unless they conflict.

[0038] The preparation method of AB-PINACA standard solutions of different concentrations in the following examples is as follows: prepare AB-PINACA solution, and then dilute it with anhydrous ethanol to obtain a series of AB-PINACA standard solutions of different concentrations. The concentrations of AB-PINACA in the AB-PINACA standard solutions in this example are (a) 1.0×10 -12 g / L; (b) 1.0×10 -11 g / L; (c) 1.0×10 -10 g / L; (d)1.0×10 -9 g / L; (e) 1.0×10 -8 g / L; (f) 1.0×10 -7 g / L; (g)1.0×10 -6 g / L; (h)1.0×10 -5 g / L; (i) 1.0×10 -4 g / L; (j) 1.0×10 -3 g / L.

[0039] Example 1

[0040] (1) Assembly of LaCoO3 / PTCA-TCPP / PIOPCs / GCE sensor

[0041] (1) Preparation of PS microspheres, PTCA-TCPP, and LaCoO3 materials:

[0042] Sodium lauryl sulfate (0.01 g), styrene (5 mL) and 20 mL of water were added to a 50 mL round-bottom flask and nitrogen was introduced to fully remove the dissolved oxygen. The mixed solution was kept at a constant temperature of 60 ° C for 30 minutes to fully emulsify, then continued to be heated to 75 ° C, 2 mL of 0.5% K2S2O8 solution was added, and the reaction was continued for 12 hours to obtain a white milky product. The product was washed with ethanol and ultrapure water multiple times, and gradient centrifugation was performed to obtain PS microspheres with uniform particle size. The particle size of the PS microspheres was about 500 nm. The purified and screened PS microspheres were heated and dried under vacuum conditions, and the obtained white powder was sealed and stored under natural conditions.

[0043] ZrCl4 (10 mg) and PTCA (35 mg) were dissolved in DMF (10 mL) under ultrasonic conditions and then heated in an 80-90°C oven for approximately 1 hour to form solution a. TCPP (10 mg) and benzoic acid (500 mg) were then dissolved in DMF (5 mL) to form solution b. Solution b was added to solution a, mixed thoroughly, and placed in a reactor and allowed to react in an oven at approximately 120°C for 24 hours. After cooling to room temperature, the mixture was washed with DMF and ultrapure water, and the resulting solid particles were dried in a vacuum oven at 140°C for 24 hours to produce PTCA-TCPP.

[0044] To a mixture of urea (0.9 g), nitric acid (65%, 3 mL), citric acid (3.1 g), and deionized water (30 mL) was added 1.6 g of La(NO₃)₃·6H₂O and 0.9 g of Co(OAc)₂·6H₂O. The solution was then heated to 80°C and stirred continuously with a magnetic stirrer until a gel formed. The gel was dried at 170°C for 12 h and finally calcined at 600°C for 6 h to crystallize. The resulting black powder, LaCoO₃, was then ground.

[0045] (2) Preparation of LaCoO3 / PTCA-TCPP / PIOPCs / GCE sensor

[0046] First, PTCA-TCPP and LaCoO3 were dispersed in DMF respectively, and ultrasonicated to make them uniformly dispersed to obtain a dispersion of PTCA-TCPP and LaCoO3 with a concentration of 1 mg / mL; PS microspheres were dispersed in deionized water and ultrasonicated to make them uniformly dispersed to obtain a dispersion of PS microspheres with a concentration of 0.5 mg / mL.

[0047] A glassy carbon electrode (diameter φ = 3 mm) was polished, cleaned, and air-dried at room temperature. 5 μL of the prepared PS microsphere dispersion was pipetted sequentially using a microsyringe. After air-drying, the electrode was then modified with 3 μL of PTCA-TCPP and LaCoO₃ dispersions, sequentially converting the PS microspheres into PIOPCs under the action of DMF. After air-drying, a LaCoO₃ / PTCA-TCPP / PIOPCs / GCE-modified electrode was obtained. Finally, a 5 μL aqueous solution of LEDC / NHS was added to activate the carboxyl groups, yielding an electrochemiluminescent sensor for detecting AB-PINACA with specific recognition capability.

[0048] (2) Detection of AB-PINACA based on LaCoO3 / PTCA-TCPP / PIOPCs / GCE sensor

[0049] (1) Drawing of standard curve

[0050] Equal amounts of AB-PINACA standard solutions of varying concentrations were applied to the electrochemiluminescence sensor described in (1) and reacted for the same amount of time to allow the electrochemiluminescence sensor to fully react with the AB-PINACA. A three-electrode system was then constructed, using AB-PINACA / LaCoO3 / PTCA-TCPP / PIOPCs / GCE as the working electrode, Ag / AgCl as the reference electrode, and a platinum electrode as the counter electrode. A PBS buffer solution containing 0.05 mol / L K2S2O8 at a pH of 7.5 was used as the electrolyte. Cyclic voltammetry was performed over a voltage range of -1.8 to 0 V, with a photomultiplier tube at 800 V and a scan rate of 0.1 V / s. The electrochemiluminescence curve was recorded. A correlation was established between the light intensity difference (ΔECL) before and after the electrochemiluminescence sensor and the AB-PINACA concentration. After analyzing the data, it was found that there was a linear relationship between ΔECL and the logarithmic value of AB-PINACA concentration. The corresponding linear regression equation was obtained by data fitting: ΔECL = 17108.74 + 1297.91 lgC (g / L), and the detection range was 1.0×10 -12 ~1.0×10 -3 g / L, and the detection limit was 1.1×10 -13 g / L.

[0051] (2) Detection of AB-PINACA in e-cigarette samples

[0052] 5 mL of a certain brand of e-cigarette liquid was placed in a 10 mL centrifuge tube, and then the centrifuge tube was shaken vigorously for 15 minutes and centrifuged at 6000 rpm for 15 minutes. Afterwards, the collected supernatant was filtered with a 0.45 μm membrane and the filtrate was transferred to a reagent bottle for further use. AB-PINACA standard solutions of different concentrations were added to the above-mentioned e-cigarette liquid for spike recovery experiments. 3 μL of e-cigarette supernatant without or with AB-PINACA standard solution was modified on the surface of the LaCoO3 / PTCA-TCPP / PIOPCs / GCE electrochemiluminescence sensor, and the concentration of AB-PINACA in the sample to be tested was calculated according to the linear regression equation obtained in step (1). The results are listed in Table 1.

[0053] In this example, PIOPCs converted from PS microspheres were used as the substrate, PTCA-TCPP was used as the luminophore, and LaCoO3 was used as the catalyst. PS microspheres, PTCA-TCPP, and LaCoO3 were modified on the surface of the glassy carbon electrode in sequence by a layered modification method to form a LaCoO3 / PTCA-TCPP / PIOPCs / GCE modified electrode. The specific morphology of each substance is shown in FIG. Figure 4As shown. The substances are bound to each other through electrostatic interactions and fixed to the electrode surface by polystyrene, which improves the electrochemiluminescence stability of the prepared sensor. In addition, the photonic band gap of PIOPCs can reflect light of the same wavelength as the luminophore PTCA-TCPP, thereby achieving spontaneous emission enhancement of the sensor's light intensity. The presence of the catalyst LaCoO3 can accelerate the decomposition of the co-reactant K2S2O8 to further enhance the sensor's ECL light intensity. The activation of the luminophore carboxyl group by the EDC / NHS solution enables the sensor to specifically recognize AB-PINACA. When trace amounts of AB-PINACA appear, the ECL intensity value is quenched by the interaction between AB-PINACA and the sensor, enabling quantitative detection of AB-PINACA. The sensor has good conductivity, stability and selectivity. Compared with other detection methods, this method also has a wider detection range and lower detection limit, enabling trace detection of AB-PINACA.

[0054] Example 2:

[0055] The specific method is similar to that of Example 1, except that the concentrations of PTCA-TCPP and LaCoO3 in step (2) are 0.5 mg / mL.

[0056] Example 3:

[0057] The specific method is similar to that of Example 1, except that the concentration of PS in step (2) is 0.1 mg / mL.

[0058] Example 4:

[0059] The specific method is similar to that of Example 1, except that the concentration of LaCoO3 in step (2) is 0.5 mg / mL.

[0060] Comparative Example 1:

[0061] (1) Preparation of PTCA-TCPP / GCE sensor

[0062] 3 μL of a 1 mg / mL PTCA-TCPP DMF dispersion was pipetted using a micropipette and drop-coated onto the surface of a pretreated glassy carbon electrode (pretreatment method was the same as in Example 1) to obtain a PTCA-TCPP / GCE chemically modified electrode. After natural drying, the electrochemiluminescence sensor element (PTCA-TCPP / GCE) was obtained.

[0063] (2) Drawing of standard curve

[0064] The PTCA-TCPP / GCE sensor prepared in step (1) was used as a sensing element, 3 μL of AB-PINACA standard solutions of different concentrations were modified on the sensor surface and reacted for 20 minutes, then used as a working electrode, Ag / AgCl as a reference electrode, and a platinum electrode as a counter electrode to form a three-electrode system, and 0.1 mol / L PBS buffer solution with pH 7.5 containing 0.05 mol / L K2S2O8 was used as an electrolyte to measure the luminescence intensity. Within the electrochemical window range of -1.8 to 0 V, a photomultiplier tube high voltage of 800 V and a scan rate of 0.1 V / s was used to perform cyclic voltammetry scanning and record the luminescence intensity-time curve. By analyzing the data, a linear relationship between the luminescence intensity difference before and after the electrochemiluminescence sensor was combined with AB-PINACA and the logarithm of the concentration of the AB-PINACA standard solution was established, and the corresponding linear regression equation was obtained.

[0065] (3) Detection of AB-PINACA in e-cigarette samples

[0066] 5 mL of a certain brand of e-cigarette liquid was placed in a 10 mL centrifuge tube, and then the centrifuge tube was shaken vigorously for 15 minutes and centrifuged at 6000 rpm for 15 minutes. Afterwards, the collected supernatant was filtered with a 0.45 μm membrane and the filtrate was transferred to a reagent bottle for further use. AB-PINACA standard solutions of different concentrations were added to the above-mentioned e-cigarette liquid for spike recovery experiments. 3 μL of e-cigarette supernatant without and with AB-PINACA standard solution was taken and modified on the surface of the PTCA-TCPP / GCE electrochemiluminescence sensor. The concentration of AB-PINACA in the sample to be tested was calculated according to the linear regression equation obtained in step (1). The results are listed in Table 1.

[0067] Comparative Example 2:

[0068] (1) Preparation of LaCoO3 / GCE sensor

[0069] Use a micropipette to transfer 3 μL of 1 mg / mL LaCoO3 DMF dispersion and drop-coat it on the surface of the pre-treated glassy carbon electrode (pre-treatment method is the same as Example 1) to obtain a LaCoO3 / GCE chemically modified electrode. After natural drying, the electrochemiluminescence test sensor element (LaCoO3 / GCE) was obtained.

[0070] (2) Drawing of standard curve

[0071] The LaCoO3 / GCE sensor prepared in step (1) was used as a sensing element, 3 μL of AB-PINACA standard solutions of different concentrations were modified on the sensor surface and reacted for 20 minutes, then used as a working electrode, Ag / AgCl as a reference electrode, and a platinum electrode as a counter electrode to form a three-electrode system, and 0.1 mol / L PBS buffer solution with pH 7.5 containing 0.05 mol / L K2S2O8 was used as an electrolyte to measure the luminescence intensity. Within the electrochemical window range of -1.8 to 0 V, a photomultiplier tube high voltage of 800 V and a scan rate of 0.1 V / s was used to perform cyclic voltammetry scanning and record the luminescence intensity-time curve. By analyzing the data, a linear relationship between the luminescence intensity difference before and after the electrochemiluminescence sensor was combined with AB-PINACA and the logarithm of the concentration of the AB-PINACA standard solution was established, and the corresponding linear regression equation was obtained.

[0072] (3) Detection of AB-PINACA in e-cigarette samples

[0073] 5 mL of a certain brand of e-cigarette liquid was placed in a 10 mL centrifuge tube, and then the centrifuge tube was shaken vigorously for 15 minutes and centrifuged at 6000 rpm for 15 minutes. Afterwards, the collected supernatant was filtered with a 0.45 μm membrane and the filtrate was transferred to a reagent bottle for further use. AB-PINACA standard solutions of different concentrations were added to the above-mentioned e-cigarette liquid for spike recovery experiments. 3 μL of e-cigarette supernatant without and with AB-PINACA standard solution was taken and modified on the surface of the LaCoO3 / GCE electrochemiluminescence sensor. The concentration of AB-PINACA in the sample to be tested was calculated according to the linear regression equation obtained in step (1). The results are listed in Table 1.

[0074] Comparative Example 3:

[0075] (1) Preparation of PS / GCE sensor

[0076] Use a micropipette to transfer 5 μL of 1 mg / mL aqueous dispersion of PS microspheres and drop-coat it on the surface of the pretreated glassy carbon electrode (pretreatment method is the same as Example 1) to obtain a PS / GCE chemically modified electrode. After natural drying, the electrochemiluminescence test sensor element (PS / GCE) was obtained.

[0077] (2) Drawing of standard curve

[0078] The PS / GCE sensor prepared in step (1) was used as a sensing element, 3 μL of AB-PINACA standard solutions of different concentrations were modified on the sensor surface and reacted for 20 minutes, then used as a working electrode, Ag / AgCl as a reference electrode, and a platinum electrode as a counter electrode to form a three-electrode system, and 0.1 mol / L PBS buffer solution with pH 7.5 containing 0.05 mol / L K2S2O8 was used as an electrolyte to measure the luminescence intensity. Within the electrochemical window range of -1.8 to 0 V, the photomultiplier tube was operated at a high voltage of 800 V and a scan rate of 0.1 V / s to perform cyclic voltammetry scanning and record the luminescence intensity-time curve. By analyzing the data, a linear relationship between the luminescence intensity difference before and after the electrochemiluminescence sensor was combined with AB-PINACA and the logarithmic value of the concentration of the AB-PINACA standard solution was established, and the corresponding linear regression equation was obtained.

[0079] (3) Detection of AB-PINACA in e-cigarette samples

[0080] 5 mL of a certain brand of e-cigarette liquid was placed in a 10 mL centrifuge tube, and then the centrifuge tube was shaken vigorously for 15 minutes and centrifuged at 6000 rpm for 15 minutes. Afterwards, the collected supernatant was filtered with a 0.45 μm membrane and the filtrate was transferred to a reagent bottle for further use. AB-PINACA standard solutions of different concentrations were added to the above-mentioned e-cigarette liquid for spike recovery experiments. 3 μL of e-cigarette supernatant without or with AB-PINACA standard solution was taken and modified on the surface of the PS / GCE electrochemiluminescence sensor. The concentration of AB-PINACA in the sample to be tested was calculated according to the linear regression equation obtained in step (1). The results are listed in Table 1.

[0081] Comparative Example 4:

[0082] (1) Preparation of PTCA-TCPP / PIOPCs / GCE sensor

[0083] 5 μL of a 1 mg / mL aqueous dispersion of PS microspheres and 3 μL of a 1 mg / mL DMF dispersion of PTCA-TCPP were respectively pipetted using a micropipette and dropwise coated onto the surface of a pretreated glassy carbon electrode (pretreatment method was the same as in Example 1) to obtain a PTCA-TCPP / PIOPCs / GCE chemically modified electrode. After natural drying, the electrochemiluminescence sensor element (PTCA-TCPP / PIOPCs / GCE) was obtained.

[0084] (2) Drawing of standard curve

[0085] The PTCA-TCPP / PIOPCs / GCE sensor prepared in step (1) was used as a sensing element, 3 μL of AB-PINACA standard solutions of different concentrations were modified on the sensor surface and reacted for 20 minutes, then used as a working electrode, Ag / AgCl as a reference electrode, and a platinum electrode as a counter electrode to form a three-electrode system, and 0.1 mol / L PBS buffer solution with pH 7.5 containing 0.05 mol / L K2S2O8 was used as an electrolyte to measure the luminescence intensity. Within the electrochemical window range of -1.8 to 0 V, a photomultiplier tube high voltage of 800 V and a scan rate of 0.1 V / s was used to perform cyclic voltammetry scanning and record the luminescence intensity-time curve. By analyzing the data, a linear relationship between the luminescence intensity difference before and after the electrochemiluminescence sensor was combined with AB-PINACA and the logarithm of the concentration of the AB-PINACA standard solution was established, and the corresponding linear regression equation was obtained.

[0086] (3) Detection of AB-PINACA in e-cigarette samples

[0087] 5 mL of a certain brand of e-cigarette liquid was placed in a 10 mL centrifuge tube, and then the centrifuge tube was shaken vigorously for 15 minutes and centrifuged at 6000 rpm for 15 minutes. Afterwards, the collected supernatant was filtered with a 0.45 μm membrane and the filtrate was transferred to a reagent bottle for further use. AB-PINACA standard solutions of different concentrations were added to the above-mentioned e-cigarette liquid for spike recovery experiments. 3 μL of e-cigarette supernatant without or with AB-PINACA standard solution was modified on the surface of the PTCA-TCPP / PIOPCs / GCE electrochemiluminescence sensor, and the concentration of AB-PINACA in the sample to be tested was calculated according to the linear regression equation obtained in step (1). The results are listed in Table 1.

[0088] Comparative Example 5:

[0089] (1) Preparation of LaCoO3 / PIOPCs / GCE sensor

[0090] Use a micropipette to transfer 5 μL of 1 mg / mL aqueous dispersion of PS microspheres and 3 μL of 1 mg / mL DMF dispersion of LaCoO3, respectively, and drop-coat them onto the surface of the pretreated glassy carbon electrode (pretreatment method is the same as Example 1) to obtain a LaCoO3 / PIOPCs / GCE chemically modified electrode. After natural drying, the sensor element (LaCoO3 / PIOPCs / GCE) for electrochemiluminescence test was obtained.

[0091] (2) Drawing of standard curve

[0092] The LaCoO3 / PIOPCs / GCE sensor prepared in step (1) was used as a sensing element, 3 μL of AB-PINACA standard solutions of different concentrations were modified on the sensor surface and reacted for 20 minutes, then used as a working electrode, Ag / AgCl as a reference electrode, and a platinum electrode as a counter electrode to form a three-electrode system, and 0.1 mol / L PBS buffer solution with pH 7.5 containing 0.05 mol / L K2S2O8 was used as an electrolyte to measure the luminescence intensity. Within the electrochemical window range of -1.8 to 0 V, a photomultiplier tube high voltage of 800 V and a scan rate of 0.1 V / s was used to perform cyclic voltammetry scanning and record the luminescence intensity-time curve. By analyzing the data, a linear relationship between the luminescence intensity difference before and after the electrochemiluminescence sensor was combined with AB-PINACA and the logarithm of the concentration of the AB-PINACA standard solution was established, and the corresponding linear regression equation was obtained.

[0093] (3) Detection of AB-PINACA in e-cigarette samples

[0094] 5 mL of a certain brand of e-cigarette liquid was placed in a 10 mL centrifuge tube, and then the centrifuge tube was shaken vigorously for 15 minutes and centrifuged at 6000 rpm for 15 minutes. Afterwards, the collected supernatant was filtered with a 0.45 μm membrane and the filtrate was transferred to a reagent bottle for further use. AB-PINACA standard solutions of different concentrations were added to the above-mentioned e-cigarette liquid for spike recovery experiments. 3 μL of e-cigarette supernatant without or with AB-PINACA standard solution was taken and modified on the surface of the LaCoO3 / PIOPCs / GCE electrochemiluminescence sensor. The concentration of AB-PINACA in the sample to be tested was calculated according to the linear regression equation obtained in step (1). The results are listed in Table 1.

[0095] Comparative Example 6:

[0096] (1) Preparation of LaCoO3 / PTCA-TCPP / GCE sensor

[0097] Use a micropipette to transfer 3 μL of 1 mg / mL PTCA-TCPP DMF dispersion and 3 μL of 1 mg / mL LaCoO3 DMF dispersion, respectively, and drop-coat them onto the surface of the pretreated glassy carbon electrode (pretreatment method is the same as Example 1) to obtain a LaCoO3 / PTCA-TCPP / GCE chemically modified electrode. After natural drying, the electrochemiluminescence test sensor element (LaCoO3 / PTCA-TCPP / GCE) was obtained.

[0098] (2) Drawing of standard curve

[0099] The LaCoO3 / PTCA-TCPP / GCE sensor prepared in step (1) was used as a sensing element, 3 μL of AB-PINACA standard solutions of different concentrations were modified on the sensor surface and reacted for 20 minutes, then used as a working electrode, Ag / AgCl as a reference electrode, and a platinum electrode as a counter electrode to form a three-electrode system, and 0.1 mol / L PBS buffer solution with pH 7.5 containing 0.05 mol / L K2S2O8 was used as an electrolyte to measure the luminescence intensity. Within the electrochemical window range of -1.8 to 0 V, a photomultiplier tube high voltage of 800 V and a scan rate of 0.1 V / s was used to perform cyclic voltammetry scanning and record the luminescence intensity-time curve. By analyzing the data, a linear relationship between the luminescence intensity difference before and after the electrochemiluminescence sensor was combined with AB-PINACA and the logarithm of the concentration of the AB-PINACA standard solution was established, and the corresponding linear regression equation was obtained.

[0100] (3) Detection of AB-PINACA in e-cigarette samples

[0101] 5 mL of a certain brand of e-cigarette liquid was placed in a 10 mL centrifuge tube, and then the centrifuge tube was shaken vigorously for 15 minutes and centrifuged at 6000 rpm for 15 minutes. Afterwards, the collected supernatant was filtered with a 0.45 μm membrane and the filtrate was transferred to a reagent bottle for further use. AB-PINACA standard solutions of different concentrations were added to the above-mentioned e-cigarette liquid for spike recovery experiments. 3 μL of e-cigarette supernatant without or with AB-PINACA standard solution was modified on the surface of the LaCoO3 / PTCA-TCPP / GCE electrochemiluminescence sensor, and the concentration of AB-PINACA in the sample to be tested was calculated according to the linear regression equation obtained in step (1). The results are listed in Table 1.

[0102] Table 1 Test results of an electronic cigarette sample

[0103]

[0104] Remark: a It is the average value of three measurements.

[0105] As shown in Table 1, samples were measured three times in parallel. The spiked recovery rate for detection in Example 1 ranged from 96% to 105%, with a relative standard deviation of less than 5%, demonstrating excellent recovery. These experimental results demonstrate that, without modification using the LaCoO3 / PTCA-TCPP / PIOPCs composite, glassy carbon electrodes modified with LaCoO3, PTCA-TCPP, or PS alone, and then assembled into a sensor element, are unable to detect AB-PINACA. Therefore, the sensor of the present invention is suitable for detecting AB-PINACA in e-cigarettes.

[0106] Based on the above verification, the present invention constructs a new method for rapid and sensitive detection of AB-PINACA based on the electrochemiluminescence quenching effect of AB-PINACA on the LaCoO3 / PTCA-TCPP / PIOPCs / GCE system. The substances bind to each other through electrostatic interactions and are immobilized on the electrode surface by polystyrene, improving the electrochemiluminescence stability of the prepared sensor. Furthermore, the photonic band gap of PIOPCs can reflect light of the same wavelength as the luminophore PTCA-TCPP, enhancing the sensor's spontaneous emission intensity. The presence of the LaCoO3 catalyst accelerates the decomposition of the coreactant K2S2O8, further increasing the sensor's ECL intensity. The activation of the carboxyl groups of the luminophore by the EDC / NHS solution enables the sensor's specific recognition of AB-PINACA. When trace amounts of AB-PINACA are present, the interaction between AB-PINACA and the sensor quenches the ECL intensity, enabling quantitative detection of AB-PINACA. The sensor has good conductivity, stability and selectivity. Compared with other detection methods, this method also has a wider detection range and lower detection limit, which can achieve trace detection of AB-PINACA.

[0107] The above description is only a preferred specific embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any technician familiar with the technical field, within the technical scope disclosed by the present invention, who makes equivalent replacements or changes based on the technical solutions and concepts of the present invention, should be covered by the scope of protection of the present invention.

Claims

1. An electrochemiluminescence sensor based on inverse opal photonic crystal, characterized in that: The invention comprises a glassy carbon electrode surface modified with a LaCoO3 / PTCA-TCPP / PIOPCs composite material to obtain LaCoO3 / PTCA-TCPP / PIOPCs / GCE; wherein the polystyrene inverse opal is formed by polystyrene microspheres under the action of dimethylformamide; and the LaCoO3 / PTCA-TCPP composite material is formed by LaCoO3 and PTCA-TCPP through electrostatic interaction. The preparation method of the electrochemiluminescence sensor based on inverse opal photonic crystals comprises the following steps: dispersing polystyrene microspheres in deionized water and uniformly dispersing them by ultrasonication to obtain a polystyrene microsphere dispersion; dispersing PTCA-TCPP and LaCoO3 in dimethylformamide and uniformly dispersing them by ultrasonication to obtain a PTCA-TCPP dispersion and a LaCoO3 dispersion; sequentially modifying the polystyrene microsphere dispersion, the PTCA-TCPP dispersion, and the LaCoO3 dispersion on the surface of a clean glassy carbon electrode, converting the polystyrene microspheres into PIOPCs under the action of dimethylformamide in the PTCA-TCPP and LaCoO3 dispersions, and naturally drying the composite material LaCoO3 / PTCA-TCPP / PIOPCs-modified glassy carbon electrode LaCoO3 / PTCA-TCPP / PIOPCs / GCE; The preparation method of PTCA-TCPP is as follows: ZrCl4 and 3,4,9,10-perylenetetracarboxylic acid are dissolved in dimethylformamide under ultrasonic conditions, and heated to 80-90°C for complete reaction to form solution a; meso-tetra(4-carboxyphenyl)porphine and benzoic acid are dissolved in dimethylformamide to form solution b; solution b is added to solution a, mixed and reacted at 115-125°C until complete; cooled to room temperature, washed, and vacuum dried to obtain luminescent PTCA-TCPP solid particles; wherein the mass ratio of ZrCl4 to 3,4,9,10-perylenetetracarboxylic acid is 10:35; and the mass ratio of meso-tetra(4-carboxyphenyl)porphine to benzoic acid is 10:

500.

2. The method for preparing an electrochemiluminescence sensor based on an inverse opal photonic crystal according to claim 1, characterized in that: The preparation method comprises the following steps: dispersing PS microspheres in deionized water and uniformly dispersing them by ultrasonication to obtain a PS microsphere dispersion; dispersing PTCA-TCPP and LaCoO3 in dimethylformamide respectively and uniformly dispersing them by ultrasonication to obtain a PTCA-TCPP dispersion and a LaCoO3 dispersion; sequentially modifying the PS microsphere dispersion, the PTCA-TCPP dispersion, and the LaCoO3 dispersion on the surface of a clean glassy carbon electrode, converting the PS microspheres into PIOPCs under the action of the dimethylformamide in the PTCA-TCPP and LaCoO3 dispersions, and naturally drying the composite material LaCoO3 / PTCA-TCPP / PIOPCs-modified glassy carbon electrode LaCoO3 / PTCA-TCPP / PIOPCs / GCE.

3. The method for preparing an electrochemiluminescence sensor based on an inverse opal photonic crystal according to claim 2, wherein: The PS microspheres have a particle size of 475-525 nm and are prepared by the following method: sodium lauryl sulfate, styrene, and water are added to a reactor, nitrogen is introduced to fully remove dissolved oxygen, and a mixed solution is obtained; the mixed solution is fully emulsified at 58-62°C, the temperature is continuously raised to 73-77°C, a 5% by mass concentration of K2S2O8 solution is added, and the reaction is continued for 10-13 hours to obtain a white milky product; the product is washed, gradient centrifuged, and vacuum dried to obtain PS microspheres with uniform particle size; wherein the mass volume ratio of sodium lauryl sulfate:styrene:water is 1 g:500 mL:2000 mL; the amount of K2S2O8 solution added is calculated based on the volume of styrene, and the volume ratio of styrene:5% K2S2O8 is 2-2.5:1; The preparation method of LaCoO3 is as follows: La(NO3)3·6H2O and Co(OAc)2·6H2O are added to a mixed solution of urea, nitric acid, citric acid and deionized water, and then the solution is heated to 75-85°C and continuously stirred with a magnetic stirrer until a gel is produced; the gel is dried at 170-175°C for 12-13 hours, and finally calcined at 600°C for 6 hours to crystallize, and ground to obtain black powder LaCoO3; wherein the mass ratio of urea:nitric acid:citric acid is 0.9:2.9 g:3.1 g; and the molar ratio of La(NO3)3·6H2O to Co(OAc)2·6H2O is 2-3:

1.

4. The method for preparing an electrochemiluminescence sensor based on an inverse opal photonic crystal according to claim 2, wherein: The concentration of the aqueous dispersion of PS microspheres was 0.1-0.5 mg / mL; the droplet volume was 70 μL / cm 2 .

5. The method for preparing an electrochemiluminescence sensor based on an inverse opal photonic crystal according to claim 2, wherein: The modification mass ratio of PTCA-TCPP to LaCoO3 was 1:1; the concentration of PTCA-TCPP DMF dispersion was 0.5-1 mg / mL; the drop coating volume was 28 μL / cm 2 The concentration of LaCoO3 DMF dispersion is 0.5-1 mg / mL; the drop coating volume is 28 μL / cm 2 .

6. The method for preparing an electrochemiluminescence sensor based on an inverse opal photonic crystal according to claim 2, wherein: The preparation method further includes activating carboxyl groups on the surface of the glassy carbon electrode modified with the LaCoO3 / PTCA-TCPP / PIOPCs composite material using an aqueous solution of EDC / NHS; the mass ratio of EDC to NHS in the aqueous solution of EDC / NHS is 4:1, and the modification amount is 56 μL / cm 2 .

7. The use of the electrochemiluminescence sensor based on inverse opal photonic crystal according to claim 1, characterized in that: A three-electrode system was composed of LaCoO3 / PTCA-TCPP / PIOPCs / GCE as the working electrode, Ag / AgCl as the reference electrode, and a platinum wire electrode as the counter electrode. The synthetic cannabinoid AB-PINACA in the sample was incubated and fixed to the surface of the sensor, and the synthetic cannabinoid AB-PINACA was detected by the change in the generated electrochemiluminescence signal.

8. The use of the electrochemiluminescence sensor based on inverse opal photonic crystal according to claim 7, characterized in that: The sample volume was 3 μL and the incubation time was 20-30 min.

9. The use of the electrochemiluminescence sensor based on inverse opal photonic crystal according to claim 7, characterized in that: Using K2S2O8 in PBS buffer solution as the electrolyte, cyclic voltammetry was performed in the electrochemical window range of -1.8~0 V with a photomultiplier tube high voltage of 800 V and a scan rate of 0.1 V / s. The luminescence intensity was detected and the concentration of AB-PINACA in the sample was calculated according to the linear regression equation.

10. The use of the electrochemiluminescence sensor based on inverse opal photonic crystal according to claim 7, characterized in that: The PBS buffer solution of K2S2O8 contains 0.05 mol / L K2S2O8 and 0.1 mol / L PBS, and its pH is 7.5.

Images