A Ti3C2@MnO2 heterostructure material, its preparation method and application

Abstract

This invention discloses a Ti3C2@MnO2 heterostructure material, its preparation method, and its applications. Using Ti3AlC2, LiF, and HCl as precursors, Ti3C2 was prepared by stripping Al atoms from the Ti3AlC2 precursor using a weak acid etching method. The Ti3C2@MnO2 heterostructure material was then prepared using a microwave method with Ti3C2 as the matrix and potassium permanganate as the manganese source. The prepared Ti3C2@MnO2 heterostructure material exhibits good catalytic performance, strong electron transport capability, and stable physicochemical properties. Furthermore, based on the oxidase-like activity and photoelectrocatalytic activity of the Ti3C2@MnO2 heterostructure material, this invention constructs a colorimetric and photoelectric sensor for GSH detection, which possesses excellent anti-interference ability and high selectivity. This sensor has dual signal measurement capabilities, increasing the dynamic range of the measurement and providing built-in correction for environmental and concentration factors, thus solving the problems of high background signal interference and low sensitivity in traditional sensors.

Description

Technical Field

[0001] This invention relates to the field of nano-oxidase preparation technology, and more specifically, to a Ti3C2@MnO2 heterostructure material, its preparation method, and its application. Background Technology

[0002] Glutathione (GSH) is a tripeptide containing a γ-amide bond and a thiol group, composed of glutamic acid, cysteine, and glycine. It is an important intracellular regulatory metabolic substance, participating in the tricarboxylic acid cycle and glucose metabolism, and activating various enzymes, playing a crucial role in human life activities. GSH also helps maintain normal immune system function, possessing antioxidant and detoxification properties. Abnormal GSH levels in the body are associated with the pathogenesis of various diseases, including Alzheimer's disease, AIDS, cancer, liver damage, and cardiovascular diseases. Therefore, rapid detection of glutathione levels in the human body is of great significance for disease treatment and biotechnology development. Currently, methods for detecting GSH mainly include mass spectrometry, fluorescence, electrochemistry, and surface-enhanced Raman scattering. However, most methods require complex instruments, cumbersome pretreatment, or high detection costs, which significantly hinder their practicality. Therefore, designing a highly sensitive, low-cost, fast-response, and simple-to-operate method for GSH detection is of great importance.

[0003] Mn-based oxides (such as MnO, MnO2, Mn2O3, and Mn3O4), Mn-based metal-organic frameworks, and Mn single-atom nanomaterials can exhibit various types of enzyme-mimicking activities. Among them, MnO2, as a photoactive material, has characteristics such as a narrow band gap, good conductivity, and unique catalytic redox properties. MnO2 nanomaterials possess oxidase-like properties because they can activate molecular oxygen to produce reactive oxygen species (ROS). They can directly react with the chromogenic substrate 3,3',5,5'-tetramethylbenzidine (TMB) to produce a colorimetric reaction. Therefore, the oxidase-like activity of MnO2 can be applied to the detection of biomarkers in serum and the detection of small molecules (ascorbic acid, glutathione, and cysteine). However, the oxidase activity of MnO2 itself needs further improvement. CN120605772A discloses a method for producing MnO2@ZIF-67 composite nanoparticles with high oxidase activity, which involves reacting MnO2 with PVP, cobalt nitrate hexahydrate, and 2-methylimidazole to generate MnO2@ZIF-67 composite nanoparticles. By introducing a cobalt-based metal framework component, the surface potential of the MnO2 nanoparticles is improved, changing from a negative surface potential to a positive potential, thereby enhancing the binding ability of nanozymes to cells with negative surface potentials and improving detection sensitivity. The nanocomposite material synthesized in this patent exhibits higher activity than the single component MnO2, while also solving the problem of low enzymatic activity of nanozymes caused by the poor aggregation and dispersibility of MnO2. Furthermore, this patent utilizes the oxidase-like activity of MnO2@ZIF-67 composite nanoparticles to establish a colorimetric sensor. It leverages the catalytic property of MnO2@ZIF-67 composite nanoparticles to rapidly react with 1,3,3,5,5-tetramethylbenzidine (TMB) to produce a deep blue color. By co-incubating TMB and nanoparticles, the absorbance change at 652 nm, based on the colorimetric reaction of TMB redox, achieves the detection of reducing substances. This sensor can be used to detect ascorbic acid (AA), cysteine ​​(Cys), and glutathione (GSH). However, this sensor detects the target analyte through a single signal, which is susceptible to interference from factors such as background noise, sensor concentration, instrument efficiency, and environmental conditions, affecting the accuracy of the detection results. Summary of the Invention

[0004] The main technical problem to be solved by this invention is to provide a Ti3C2@MnO2 heterostructure material, which addresses the shortcomings of existing catalysts such as poor catalytic performance, poor electron transport capability, and unstable physicochemical properties.

[0005] Another technical problem solved by the present invention is to provide a method for preparing the Ti3C2@MnO2 heterostructure material.

[0006] The objective of this invention is achieved through the following technical solution:

[0007] A method for preparing a Ti3C2@MnO2 heterostructure material, comprising the following steps: S1. Add LiF to hydrochloric acid solution and disperse evenly, then add Ti3AlC2 and stir evenly. React in a water bath at 38~42℃ for 10~36h. After washing and drying, obtain Ti3C2 powder. S2. Disperse Ti3C2 and KMnO4 in water at a mass ratio of 1:0.5~4, react at a microwave power of 200~2000W for 2~16 min, and obtain Ti3C2@MnO2 heterostructure material after washing and drying.

[0008] Furthermore, the mass ratio of LiF to Ti3AlC2 is 5:1.

[0009] Furthermore, the mass ratio of LiF to hydrochloric acid solution is 1:20~25, and the concentration of hydrochloric acid solution is 5~6 mol / L.

[0010] A Ti3C2@MnO2 heterostructure material is obtained by the above preparation method, and the Ti3C2@MnO2 heterostructure material is used for glutathione detection.

[0011] A colorimetric sensor for glutathione detection includes the aforementioned Ti3C2@MnO2 heterostructure material. The construction steps include: mixing the Ti3C2@MnO2 heterostructure material with an acetate-sodium acetate buffer solution, then adding TMB solution and glutathione solutions of different concentrations to react, measuring the absorbance value of the system at 652 nm, and constructing a colorimetric sensor based on the absorbance values ​​of different concentrations.

[0012] Furthermore, the pH value of the acetate-sodium acetate buffer solution is 2 to 6.

[0013] Furthermore, the concentration of the Ti3C2@MnO2 heterostructure material in the mixed solution is 0.01 mg / L to 1 mg / L.

[0014] Furthermore, the concentration of the TMB solution is 150~200 μmol / L.

[0015] Furthermore, the reaction temperature is 10~30℃, and the reaction time is 2~12min.

[0016] A photoelectric sensor for glutathione detection includes the aforementioned Ti3C2@MnO2 heterostructure material. The construction steps include: dispersing an aqueous solution of the Ti3C2@MnO2 heterostructure material onto a conductive glass, drying it under an infrared lamp, and using it as a working electrode; using an Ag / AgCl electrode and a Pt electrode as a reference electrode and a counter electrode, respectively; using sodium sulfate as an electrolyte; adding the same volume of glutathione at different concentrations to the electrolyte; stabilizing the current under visible light; and then recording the changes in the photocurrent signal under laser light. The photoelectric sensor is constructed based on the different current signals.

[0017] Compared with existing technologies, the beneficial effects are: This invention uses Ti3AlC2, LiF, and HCl as precursors. Ti3C2 was prepared by stripping Al atoms from the precursor Ti3AlC2 using a weak acid etching method. Using Ti3C2 as the matrix and potassium permanganate as the manganese source, a Ti3C2@MnO2 heterostructure material was prepared using a microwave method. The lattice defects on the surface of the Ti3C2@MnO2 heterostructure material are beneficial for adsorbing dissolved oxygen and providing a site for reaction with the substrate. Surface manganese ions can rapidly catalyze dissolved oxygen to generate highly reactive oxygen species (ROS) with strong oxidizing capabilities, improving oxidase-like activity. It exhibits good catalytic performance, strong electron transport capability, and stable physicochemical properties. Based on the oxidase-like activity and photoelectrocatalytic activity of the Ti3C2@MnO2 heterostructure material, this invention constructs a colorimetric and photoelectric sensor for the detection of GSH. The sensor has excellent anti-interference ability and high selectivity, and can selectively detect GSH even under interference from several common cations and small biomolecules. In addition, it has a dual-signal measurement function, which can increase the dynamic range of measurement and provide built-in correction for environmental and concentration factors, thereby improving the accuracy of detection results. Attached Figure Description

[0018] Figure 1 These are SEM images of Ti3AlC2, Ti3C2, and Ti3C2@MnO2. A is the SEM image of Ti3AlC2, B is the SEM image of Ti3C2, C is the SEM image of Ti3C2@MnO2, D is the EDX image of Ti3C2@MnO2, E is the SEM image of Ti3C2@MnO2, and F1 are the elemental images of C, O, Mn, and Ti in Ti3C2@MnO2, respectively. Figure 2 In the image, (A), (B), (C), and (D) are the XRD, UV-vis, FL, and FT-IR images of Ti3C2, Ti3AlC2, and Ti3C2@MnO2, respectively. Figure 3(A) shows the UV-Vis spectrum for different Ti3C2 synthesis times; (B) shows the UV-Vis spectrum for different mass ratios; and (C) shows the UV-Vis spectrum for different reaction times. Figure 4 (A) shows the UV-Vis images of different solution systems, (B) shows the UV-Vis images of the TMB+Ti3C2@MnO2 system in saturated nitrogen, saturated oxygen and air, respectively, and (C) shows the photocurrent response of the Ti3C2@MnO2 composite in electrolytes containing different concentrations of GSH. Figure 5 This is a graph showing the optimization of GSH detection conditions. (A) shows the effect of pH on the detection system, (B) shows the effect of reaction time on the detection system, (C) shows the effect of reaction temperature on the detection system, and (D) shows the effect of TMB concentration on the detection system.

[0019] Figure 6 (A) shows the UV-Vis plot of the interaction between TMB and different concentrations of GSH under optimal conditions, and (B) shows the linear curve of GSH in the range of 5-45 µmol / L. Figure 7 In the middle (A), the electrochemical impedance spectroscopy (EIS) of the T3C2 / FTO and Ti3C2@MnO2 composite / FTO electrodes is shown, and (B) the photocurrent response (it) of the T3C2 / FTO and Ti3C2@MnO2 composite / FTO electrodes in 0.2 mol / L Na2SO4 solution is shown. Figure 8 (A) is the photoelectric diagram of the interaction between Ti3C2@MnO2 and GSH at different concentrations, and (B) is the linear curve of GSH in the range of 40-280 µM. Figure 9 (A) Examination of GSH interference: (1) Without GSH, (2-10) are NaCl+GSH, KCl+GSH, CaCl2+GSH, MgCl2+GSH, FeCl3+GSH, glucose+GSH, histidine+GSH, lysine+GSH, ascorbic acid+GSH. The GSH concentration is 1 mM, and the concentration of other interferences is 10 mM. (B) Examination of GSH selection: (1) Without GSH, (2-11) are NaCl, KCl, CaCl2, MgCl2, FeCl3, glucose, histidine, lysine, ascorbic acid, GSH. The GSH concentration is 1 mM, and the concentration of other interferences is 10 mM.

[0020] Detailed implementation method.

[0021] The following examples further explain and clarify the invention, but the specific examples do not limit the invention in any way.

[0022] Example 1 This embodiment provides a method for preparing a Ti3C2@MnO2 heterostructure material, the steps of which include: Preparation of S1.Ti3C2; First, 10 mL of 12 mol / L hydrochloric acid and 10 mL of ultrapure water were mixed, and 1 g of LiF was added. The mixture was stirred evenly for 30 min. Then, 0.2 g of Ti3AlC2 was weighed and added to the reaction vessel in small batches. After stirring evenly, the mixture was placed in a constant temperature water bath at 40 ℃ and reacted for 24 h. After the reaction was completed, the solution was removed and washed three times alternately with ultrapure water and anhydrous ethanol. When the pH of the supernatant was >6, washing was stopped, and the supernatant was not removed. The solution was then directly sonicated for 30 min. Finally, the supernatant was removed by centrifugation and then freeze-dried for 8 h to obtain Ti3C2 powder.

[0023] Preparation of S2.Ti3C2@MnO2 heterostructure materials; Mix 0.1 g Ti3C2 and 0.1 g KMnO4 with 10 mL of ultrapure water. Then place the mixture in a microwave oven and react at 1000 W for 10 min. After the solution has cooled to room temperature, centrifuge at 3500 r / min for 5 min, wash the precipitate three times with water and ethanol, and finally dry it in a 70 ℃ oven for 8 h to obtain Ti3C2@MnO2 heterojunction powder.

[0024] (1) Characterization by scanning electron microscopy (SEM) and energy-dispersive X-ray spectroscopy (EDX): such as Figure 1 A and Figure 1 As shown in Figure B, the interlayer spacing of Ti3C2 is significantly larger than that of Ti3AlC2. This is because the Al layer in Ti3AlC2 has been removed. The unique accordion-like multilayer nanosheet structure of Ti3C2 is due to the ultrasonic treatment following the removal of the Al layer. Figure 1 As shown in Figure C, many sheet-like and spherical substances are aggregated on the surface of Ti3C2@MnO2. This is because Ti3C2 undergoes an oxidation reaction with KMnO4, and the resulting manganese dioxide nanosheets are aggregated on its surface.

[0025] Figure 1 The EDX mapping diagram of Ti3C2@MnO2 shown in Figure D indicates that Ti3C2@MnO2 is mainly composed of C, O, Ti and Mn elements.

[0026] (2) X-ray diffraction (XRD) characterization: Figure 2 As shown in Figure A, the XRD curve of Ti3AlC2 is in 2... θThe X-ray diffraction peaks at 19.1°, 34.0°, 38.9°, 41.8°, 48.6°, 56.7°, and 60.2° correspond to (006), (101), (104), (105), (107), (109), and (110) diffraction peaks, respectively. In Ti3C2, the (004) peak broadens, and the disappearance of the (006) and (104) characteristic peaks indicates that Al atoms in the material have been completely removed. According to JCPDS No. 44-0141 card, the X-ray diffraction peaks at 38.1° and 59.0° belong to the (310) and (330) crystal planes of α-MnO2, indicating the formation of MnO2 nanolayers.

[0027] (3) Characterization by UV-Vis diffuse reflectance spectroscopy and fluorescence spectroscopy: such as Figure 2 As shown in Figure B, the absorption wavelength range of the Ti3C2@MnO2 composite material is significantly wider than that of Ti3AlC2. Figure 2 As shown in Figure C, after obtaining the fluorescence intensities of Ti3AlC2, Ti3C2, and Ti3C2@MnO2, the fluorescence intensity of Ti3C2@MnO2 is lower than that of Ti3C2 and Ti3AlC2. This is because the photon-induced electrons of Ti3C2@MnO2 have difficulty returning to the ground state, indicating that Ti3C2@MnO2 exhibits lower electronic activity. The hole-to-recombination ratio was optimized, resulting in excellent photoelectrochemical activity.

[0028] (4) Fourier transform infrared spectroscopy (FT-IR) characterization: such as Figure 2 As shown in D, 3460 cm -1 The peak at 1618-1383 cm⁻¹ is attributed to the stretching vibration absorption peak of the -OH band. -1 There are strong spectral bands within the range, which is consistent with C=O and CC.

[21] It is related to the stretching vibration.

[0029] Example 2 This embodiment is based on the preparation process of Example 1, and optimizes the Ti3C2 synthesis time, the mass ratio of Ti3C2 to KMnO4, and the reaction time parameters.

[0030] (1) Keeping the amounts of LiF and HCl constant, Ti3C2 was synthesized at different times, such as Figure 3 As shown in Figure A, the Ti3C2@MnO2 / TMB system synthesized for 24 h exhibits the highest absorbance at 652 nm, indicating that the Ti3C2@MnO2 composite synthesized for 24 h demonstrates the strongest catalytic oxidation ability of TMB. Therefore, the optimal synthesis time for Ti3C2 is 24 h.

[0031] (2) The synthesis time of Ti3C2 was controlled to be 24 h, the microwave time of Ti3C2@MnO2 was 5 min, and different mass ratios of Ti3C2 to KMnO4 were set. For example... Figure 3 As shown in Figure B, when the mass ratio of Ti3C2 to KMnO4 is 1:1, the Ti3C2@MnO2 / TMB system exhibits the highest absorbance at 652 nm. Therefore, the Ti3C2@MnO2 composite with a mass ratio of 1:1 demonstrates a stronger catalytic oxidation ability of TMB. (3) The synthesis time of Ti3C2 was fixed at 24 h, the mass ratio was 1:1, and different microwave reaction times were set. For example... Figure 3 As shown in Figure C, the Ti3C2@MnO2 / TMB system exhibits the highest absorbance at 652 nm when the reaction time is 10 min, indicating that the Ti3C2@MnO2 composite with a reaction time of 10 min has the strongest catalytic oxidation ability of TMB.

[0032] Example 3 This embodiment provides a colorimetric sensor for glutathione detection, the steps of which include: First, 40 μL of Ti3C2@MnO2 (0.1 mg / mL) was diluted into 3.91 mL of acetate-sodium acetate buffer solution (0.2 mol / L, pH=4.0), and 50 μL of TMB (16 mM) was added. After reacting at room temperature for 5 min, the UV-Vis spectrum was recorded using a UV-Vis spectrometer, and the absorbance value at 652 nm was recorded.

[0033] Take 40 μL of Ti3C2@MnO2 (0.1 mg / mL), 3.87 mL of acetate-sodium acetate buffer solution (0.2 mol / L, pH=4.0), 50 μL of TMB (16 mM) and 40 μL of GSH solutions of different concentrations and mix them.

[0034] Finally, the mixed solution was reacted at room temperature for 5 min, and the absorbance value at 652 nm was measured.

[0035] like Figure 4 As shown in Figure A, without the addition of a catalyst, TMB cannot be oxidized by dissolved oxygen in water, and the absorbance of the reaction solution at 652 nm remains almost constant within 30 min. Upon addition of the Ti3C2@MnO2 composite, the absorbance of the reaction solution at 652 nm increases significantly, reaching its maximum value within 10 min, and then remains constant. After adding GSH solution to the Ti3C2@MnO2 reaction system, the absorbance of the reaction solution at 652 nm decreases significantly, reaching its minimum value at 5 min, and then remains constant.

[0036] The reactions of the TMB+Ti3C2@MnO2 system under solution conditions filled with saturated nitrogen, saturated oxygen, and air were respectively carried out, as follows: Figure 4 As shown in Figure B, the colorimetric system exhibits the highest absorbance under saturated oxygen conditions, indicating that dissolved oxygen in the solution adsorbs onto the catalyst surface, generating free radicals. These free radicals subsequently oxidize TMB to oxTMB, causing the solution to gradually change from gray to blue-green. When GSH is added to the TMB+Ti3C2@MnO2 system, a redox reaction occurs due to the reducing effect of GSH. oxTMB is reduced to TMB by GSH, and GSH is oxidized to oxidized glutathione (GSSH). The decrease in the oxTMB content in the system leads to a gradual decrease in the absorbance of the solution at 652 nm, resulting in a lighter solution color. Therefore, the UV absorbance of oxTMB can be measured to detect GSH.

[0037] Example 4 This embodiment is based on Example 3 and optimizes the parameters of pH, reaction time, temperature and TMB concentration.

[0038] (1) The effect of pH on the detection system: such as Figure 5 As shown in Figure A, the absorbance (Abs.) at 652 nm reaches its maximum at pH 4.0. This is because Ti3C2@MnO2 exhibits excellent oxidase-like activity under weakly acidic conditions. Therefore, the optimal pH is 4.0.

[0039] (2) Effect of reaction time on the detection system: The effect of different reaction times between 0 and 10 min on UV absorbance was investigated, with an interval of 2 min. The experimental results are as follows: Figure 5 As shown in Figure B, after adding GSH to the system and reacting at room temperature for 5 minutes, the UV absorbance of the system at 652 nm dropped to its lowest point, indicating that the optimal reaction time after adding GSH is 5 minutes.

[0040] (3) The effect of reaction temperature on the detection system: such as Figure 5 As shown in Figure C, the UV absorbance increases with increasing temperature. At higher temperatures, the solution color gradually deepens, indicating that the inhibition of the reaction of TMB catalyzed by GSH on Ti3C2@MnO2 weakens.

[0041] (4) The effect of TMB concentration on the detection system: such as Figure 5 As shown in D, the absorbance of the reaction system at 652 nm increases with the increase of TMB concentration when the amount of fixed enzyme catalyst is increased, and the absorbance no longer increases when TMB is completely converted to oxTMB.

[0042] Example 5 This embodiment provides the performance of GSH detection based on Ti3C2@MnO2 colorimetric sensor. Under optimal conditions, different concentrations of GSH were added to monitor A at 652 nm. Figure 6 As shown in A (where A 0 means no GSH is added; A (The absorbance of oxTMB is 652 nm, which is the absorbance of the added GSH). As the GSH content in the system increases, the absorbance of oxTMB gradually decreases, and the solution gradually changes from blue to colorless.

[0043] like Figure 6 As shown in Figure B, when the GSH concentration is within the range of 5-45 µmol / L, the absorbance of the system shows a linear relationship with the GSH concentration, and the linear regression equation is: y = 0.01822x + 0.02786 R 2 =0.996 Where y is the absorbance at 652 nm; x is the concentration of GSH. In this embodiment, the detection limit for GSH is 1.55 µmol / L (S / N=3). S and N are defined as signal intensity and background signal intensity, respectively. The LOD is estimated using a baseline noise method with a signal-to-noise ratio (S / N) of 3. The response values ​​of the material to GSH shown in Table 1 demonstrate that Ti3C2@MnO2 has acceptable sensitivity.

[0044] Table 1

[0045] Example 6 This embodiment provides a photoelectric sensor for glutathione detection, the steps of which include: First, 5 mg of Ti3C2@MnO2 heterojunction was mixed with 1 mL of ultrapure water and sonicated for 30 min to disperse it. Then, 50 μL of the mixed solution was transferred by pipette and dropped onto fluorine-doped SnO2 transparent conductive glass (FTO), and dried under an infrared lamp. The dropping was repeated 3 times.

[0046] The prepared FTO was then used as the working electrode in the photoelectric experiment, with an illumination area of ​​approximately 1 cm². 2 Saturated Ag / AgCl and Pt electrodes were used as the reference and counter electrodes, respectively. The electrolyte was a 0.2 mol / L sodium sulfate solution, and a 300 W LED lamp was used to provide a visible light source. After the current stabilized, the response was recorded in both the "on" and "off" states of the laser.

[0047] Finally, GSH of different concentrations with the same volume (40 μL) was added to the electrolyte, and the changes in photocurrent signal were recorded.

[0048] like Figure 4 As shown in C, in the photoelectric experiment, the prepared electrode was used as the working electrode. Different concentrations of GSH solution were gradually added to the 0.2 mol / L sodium sulfate electrolyte. The photocurrent density with added GSH solution was significantly higher than that without added GSH solution. Therefore, GSH can be detected by constructing a photoelectric sensor.

[0049] Electrochemical impedance spectroscopy (EIS) measurements were performed on Ti3C2 and Ti3C2@MnO2 composites, such as... Figure 7 As shown in Figure A, the arc radius of the Ti3C2@MnO2 composite modified electrode is smaller than that of the Ti3C2 modified electrode. This indicates that the Ti3C2@MnO2 composite exhibits the most efficient charge transfer. Furthermore, the PEC responses of different modified electrodes (Ti3C2 / FTO and Ti3C2@MnO2 composite / FTO) were measured. Figure 7 As shown in Figure B, the Ti3C2@MnO2 composite / FTO electrode exhibits the largest photocurrent under visible light irradiation compared to the Ti3C2 / FTO electrode. This is because the Ti3C2@MnO2 composite / FTO electrode can transfer photogenerated electrons and generate electron-hole pairs under visible light irradiation, resulting in the maximum photocurrent signal. Therefore, the Ti3C2@MnO2 composite possesses excellent charge separation and efficient electron transfer capabilities, thus achieving superior photoelectrochemical performance.

[0050] Example 7 This embodiment is based on the photoelectric sensor used in Embodiment 6 to detect the performance of GSH. For example... Figure 8 As shown in A (where I 0 and I (These are the photocurrent values ​​with and without GSH, respectively.) As the GSH content in the system increases, the photocurrent gradually increases. Figure 8 As shown in Figure B, when the GSH concentration ranges from 40 to 280 µmol / L, the absorbance of the system exhibits a linear relationship with the GSH concentration. The linear regression equation is as follows: y = 0.04159x + 0.00191 R 2 =0.978 Where y is the photocurrent density and x is the concentration of GSH.

[0051] Example 8 This embodiment provides an interference and selectivity experiment based on colorimetry. GSH concentration was 1 mM, and K was tested at all concentrations of 10 mM. + Na + Mg 2+ Ca 2+ Fe 3+Selective responses to lysine, histidine, ascorbic acid, and glucose. The interference test for GSH detection by colorimetric method is as follows: Ti3C2@MnO2 complex (0.1 mg / mL), TMB (0.2 mM), GSH (1 mM), and different interfering substances (10 mM) were added to an acetate-sodium acetate buffer solution (0.2 mol / L, pH 4.0). After the mixture was incubated at 25 °C for 5 min, the change in Abs. value at 652 nm was monitored by a UV-Vis spectrophotometer.

[0052] like Figure 9 As shown in Figure A, the changes in Abs. between the addition and absence of interfering substances are not significantly different, therefore it can be said that these interfering substances have little impact on GSH. The selectivity test for GSH is the same as the interference test, except that the solution does not contain GSH. Although the content of other substances is 10 times higher than that of GSH, as... Figure 9 As shown in Figure B, the Abs. of the solution with added GSH decreased significantly, while the Abs. value of the solution without added GSH was not much different from that of the original solution. Therefore, this method has high selectivity and can be used for the detection of real samples.

[0053] Example 9 This embodiment uses a spiking method to examine the practicality of the constructed method. Experimental results are shown in Table 2. Method A, using a colorimetric sensor, determined the amount of GSH in the diluted serum sample to be 12.11 µM. Method B, using a photoelectric sensor constructed with a Ti3C2@MnO2 heterostructure for glutathione detection, determined the amount of GSH in serum to be 54.05 µM. The recovery rate of GSH obtained by the spiking method in Method A was between 100.2% and 105.2%, while the recovery rate in Method B was between 94.96% and 100.99%. Therefore, the colorimetric and photoelectric sensors based on the Ti3C2@MnO2 heterostructure that we proposed can be successfully used for the detection of GSH in serum.

[0054]

[0055] Obviously, the above embodiments of the present invention are merely examples for clearly illustrating the present invention, and are not intended to limit the implementation of the present invention. Those skilled in the art can make other variations or modifications based on the above description. It is neither necessary nor possible to exhaustively describe all embodiments here. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of the present invention should be included within the scope of protection of the claims of the present invention.

Claims

1. A method for preparing a Ti3C2@MnO2 heterostructure material, characterized in that the steps include... include: S1. Add LiF to hydrochloric acid solution and disperse evenly, then add Ti3AlC2 and stir evenly. React in a water bath at 38~42℃ for 10~36h. After washing and drying, obtain Ti3C2 powder. S2. Disperse Ti3C2 and KMnO4 in water at a mass ratio of 1:0.5~4, react at microwave power for 2~16 min, and then wash and dry to obtain Ti3C2@MnO2 heterostructure material.

2. The preparation method of the Ti3C2@MnO2 heterostructure material according to claim 1, characterized in that, The mass ratio of LiF to Ti3AlC2 is 5:

1.

3. The method for preparing the Ti3C2@MnO2 heterostructure material according to claim 1, characterized in that, The mass ratio of LiF to hydrochloric acid solution is 1:20~25, and the concentration of hydrochloric acid solution is 5~6 mol / L.

4. A Ti3C2@MnO2 heterostructure material, characterized in that, It is obtained by the preparation method described in any one of claims 1 to 3.

5. The Ti3C2@MnO2 heterostructure material according to claim 4, characterized in that, The Ti3C2@MnO2 heterostructure material is used for glutathione detection.

6. A colorimetric sensor for glutathione detection, characterized in that, The Ti3C2@MnO2 heterostructure material according to claim 4 is constructed by the following steps: mixing the Ti3C2@MnO2 heterostructure material with an acetate-sodium acetate buffer solution, then adding a TMB solution and glutathione solutions of different concentrations to react, measuring the absorbance value of the system at 652 nm, and constructing a colorimetric sensor based on the absorbance values ​​of different concentrations.

7. The colorimetric sensor for glutathione detection according to claim 6, characterized in that, The pH value of the acetate-sodium acetate buffer solution is 2 to 6.

8. The colorimetric sensor for glutathione detection according to claim 6, characterized in that, The concentration of the TMB solution is 150~200 μmol / L.

9. The colorimetric sensor for glutathione detection according to claim 6, characterized in that, The reaction temperature is 10~30℃ and the reaction time is 2~12min.

10. A photoelectric sensor for glutathione detection, characterized in that, The Ti3C2@MnO2 heterostructure material according to claim 4 is constructed by the following steps: dispersing an aqueous solution of the Ti3C2@MnO2 heterostructure material onto a conductive glass, drying it under an infrared lamp, and using it as a working electrode; using an Ag / AgCl electrode and a Pt electrode as a reference electrode and a counter electrode, respectively; using sodium sulfate as an electrolyte; adding the same volume of glutathione at different concentrations to the electrolyte; stabilizing the current under visible light; recording the changes in the photocurrent signal under laser light; and constructing a photoelectric sensor based on the different current signals.

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