A three-in-one multifunctional MoSe2@Pt nanosheet, its preparation method and application

Abstract

The application relates to a three-in-one multifunctional MoSe2@Pt nanosheet and a preparation method and application thereof. The three-in-one multifunctional MoSe2@Pt nanosheet simultaneously has peroxidase catalytic performance, fluorescence quenching performance and photothermal performance; the three-in-one multifunctional MoSe2@Pt nanosheet has an ultrathin sheet structure, a diameter of 150-200 nm, a thickness of 2-5 nm, a specific surface area of 0.21-0.51 nm ‑1 .

Description

Technical Field

[0001] This invention belongs to the field of nanomaterial design and virus detection, specifically relating to a three-in-one multifunctional MoSe2@Pt nanosheet, its preparation method, and its application in RSV virus detection. Background Technology

[0002] Respiratory syncytial virus (RSV) is a common airborne RNA virus that is a major cause of lower respiratory tract infections and bronchiolitis in children, and a significant cause of morbidity and death in the elderly and those with weakened immune systems. RSV infection not only places enormous pressure on medical resources but also seriously threatens people's lives and health, becoming a pressing global public health security issue that needs to be addressed.

[0003] As is well known, rapid diagnosis of the cause of an illness is crucial for implementing the correct treatment plan and alleviating patient suffering. Currently, the main detection technologies for RSV include enzyme-linked immunosorbent assay (ELISA), loop-mediated isothermal amplification (LAM), real-time PCR, virus isolation and culture, and colloidal gold-based immunochromatography. Among these, colloidal gold-based immunochromatography has received widespread attention due to its advantages of simple operation, rapid detection, and low cost. However, because single-modality colorimetric techniques are easily affected by external environmental and human factors, they suffer from low sensitivity and poor accuracy, limiting the application of colloidal gold technology in practical detection. Therefore, developing an immunochromatographic technique that can achieve multimodal and highly sensitive detection of RSV is of great significance. Summary of the Invention

[0004] To address the aforementioned technical challenges, the present invention aims to provide a three-in-one multifunctional MoSe2@Pt nanosheet, its preparation method, and its applications. This invention selects MoSe2, which possesses high specific surface area, excellent photothermal properties, and good biocompatibility, as the research object. Two-dimensional ultrathin MoSe2 nanosheets were prepared by ultrasonic exfoliation, and modified with Pt particles to successfully prepare MoSe2@Pt nanosheets with excellent peroxidase activity, fluorescence quenching ability, and photothermal properties. Furthermore, these nanosheets were applied to immunochromatographic detection, achieving highly sensitive detection of RSV using a three-modal approach: catalytic colorimetry, fluorescence, and photothermal analysis.

[0005] In a first aspect, the present invention provides a three-in-one multifunctional MoSe2@Pt nanosheet, which simultaneously possesses peroxidase catalytic performance, fluorescence quenching performance and photothermal performance; The described three-in-one multifunctional MoSe2@Pt nanosheets have an ultrathin sheet-like structure with a diameter of 150-200 nm, a thickness of 2-5 nm, and a specific surface area of ​​0.21-0.51 nm. -1 .

[0006] Preferably, based on the total mass of the three-in-one multifunctional MoSe2@Pt nanosheets as 100%, the mass percentage of MoSe2 is 70-90%, and the mass percentage of Pt is 10-30%.

[0007] Secondly, the present invention provides a method for preparing the above-mentioned three-in-one multifunctional MoSe2@Pt nanosheets, the preparation method comprising the following steps: S1. Molybdenum selenide powder was dissolved in chitosan aqueous solution to form a mixed solution and then ultrasonically crushed. The product was collected to obtain MoSe2 nanosheets. S2. Dissolve the MoSe2 nanosheets in deionized water, add Pt solution and stir. After centrifugation and washing, obtain the three-in-one multifunctional MoSe2@Pt nanosheets.

[0008] Preferably, the concentration of the chitosan aqueous solution is 0.2-1.5 mg / mL, more preferably 0.8 mg / mL; and the concentration of MoSe2 in the mixed solution is 10-20 mg / mL. The ultrasonic crushing power is 500W, and the ultrasonic crushing time is 6-15h.

[0009] Preferably, the method for collecting the product is as follows: first, centrifuge at a rate of 2000-5000 r / min to collect the supernatant, then centrifuge again at a rate of 6000-10000 r / min to collect the precipitate, and wash the precipitate alternately with ethanol and deionized water to obtain the MoSe2 nanosheets. The mass ratio of MoSe2 nanosheets to Pt is 1:(0.1-0.3).

[0010] Thirdly, the present invention provides an application of the above-mentioned three-in-one multifunctional MoSe2@Pt nanosheets in high-sensitivity immunochromatographic detection of RSV catalytic colorimetric-fluorescence-photothermal three-modal methods for non-disease diagnosis and treatment purposes.

[0011] Preferably, the application includes the following steps: First, the above-mentioned three-in-one multifunctional MoSe2@Pt nanosheets were dissolved in a buffer solution, then RSV-labeled antibodies were added, and the nanosheets were blocked with bovine serum albumin. The three-in-one multifunctional MoSe2@Pt immunoprobe for RSV detection was obtained by electrostatic adsorption. Then, the RSV virus solution to be tested was mixed with the three-in-one multifunctional MoSe2@Pt immunoprobe and placed in a multi-well plate. The lateral flow immunochromatographic test strip for RSV multimodal detection was inserted into the well for chromatography. After chromatography, the peroxidase catalytic performance, fluorescence quenching performance and photothermal conversion performance of the three-in-one multifunctional MoSe2@Pt nanosheets were utilized, and the colorimetric, fluorescence and temperature signals on the T line of the test strip were recorded in real time by the instrument to complete the highly sensitive immunochromatographic detection of RSV virus in three modalities of catalysis, colorimetry, fluorescence and photothermal.

[0012] Preferably, the mass ratio of RSV-labeled antibody to the three-in-one multifunctional MoSe2@Pt nanosheet is (0.01-0.05):1, and the mass ratio of RSV-labeled antibody to BSA is (0.3-1.7):1.

[0013] Preferably, the lateral flow immunochromatographic test strip for RSV multimodal detection has an RSV-coated antibody modified with CdSe / ZnS quantum dots coated on the T line and a goat anti-mouse IgG antibody coated on the C line; the streaking rates of the T line and the C line are 0.8 mg / mL and 1 mg / mL, respectively.

[0014] Preferably, the preparation process of the CdSe / ZnS quantum dot-modified RSV-coated antibody includes the following steps: (1) CdSe / ZnS quantum dots were collected by centrifugation and dispersed in MES buffer solution to obtain solution A; (2) Add EDC and NHS solutions to the above solution A and activate it by ultrasound to obtain solution B; (3) Add RSV-coated antibody to solution B, shake at room temperature, and add BSA for blocking; (4) The product was collected by centrifugation and dispersed in a PBS solution containing trehalose to obtain the CdSe / ZnS quantum dot modified RSV coated antibody.

[0015] Beneficial effects This invention selects MoSe2, which has a high specific surface area, excellent photothermal properties, and good biocompatibility, as the research object. Two-dimensional ultrathin MoSe2 nanosheets were prepared by ultrasonic exfoliation and modified with Pt particles to successfully prepare MoSe2@Pt nanosheets with excellent peroxidase activity, fluorescence quenching ability, and photothermal properties. The prepared materials were then applied to immunochromatography to prepare a catalytic colorimetric-fluorescence-photothermal multimodal immunochromatographic test strip for RSV virus detection. Compared with traditional colloidal gold technology, the sensitivity of catalytic colorimetric, fluorescence, and photothermal detection modes was improved by 5 times, 10 times, and 100 times, respectively, and all three detection modes could be completed within 20 minutes. Compared with single-modal detection technology, multimodal detection technology greatly improves the accuracy, reliability, and flexibility of detection. Attached Figure Description

[0016] Figure 1 The image shows the XRD pattern of the three-in-one multifunctional MoSe2@Pt nanosheets prepared in Example 1 of this invention. Figure 2 This is a TEM image of the three-in-one multifunctional MoSe2@Pt nanosheets prepared in Example 1 of this invention; Figure 3 The EDS spectrum of the three-in-one multifunctional MoSe2@Pt nanosheets prepared in Example 1 of this invention; Figure 4 The image shows the enzyme catalytic performance of the three-in-one multifunctional MoSe2@Pt nanosheets prepared in Example 2 of this invention. Figure 5 The image shows the photothermal properties of the three-in-one multifunctional MoSe2@Pt nanosheets prepared in Example 2 of this invention. Figure 6 The images show the immunoassay performance of the three-in-one multifunctional MoSe2@Pt nanosheets prepared in Example 2 of this invention; where (a) is the immunochromatographic result of RSV at concentrations of 0-100 ng / mL, (b) is the signal amplification result of the chromatographic color development using enzyme catalysis, (c) is the fluorescence effect of the T line of the test strips for different concentrations of RSV, and (d) is the photothermal effect of the T line of the test strips for different concentrations of RSV. Figure 7 The graph shows the detection performance of the commercial colloidal gold test strip in Comparative Example 1 for RSV. Detailed Implementation

[0017] The present invention will be further illustrated by the following embodiments. It should be understood that the following embodiments are for illustrative purposes only and are not intended to limit the present invention.

[0018] First, this invention provides a three-in-one multifunctional MoSe2@Pt nanosheet. The three-in-one multifunctional MoSe2@Pt nanosheet simultaneously possesses peroxidase catalytic activity, fluorescence quenching activity, and photothermal activity.

[0019] In some embodiments, the three-in-one multifunctional MoSe2@Pt nanosheets have an ultrathin sheet-like structure, with Pt particles uniformly distributed on the surface of the MoSe2 nanosheets, having a diameter of 150-200 nm, a thickness of 2-5 nm, and a specific surface area (surface area / volume) of 0.21-0.51 nm. -1 .

[0020] In some embodiments, with the total mass of the three-in-one multifunctional MoSe2@Pt nanosheets as 100%, the mass percentage of MoSe2 can be 70-90%, and the mass percentage of Pt can be 10-30%. The introduction of Pt particles plays a crucial role in achieving excellent peroxidase activity in the MoSe2@Pt nanosheets. If the mass percentage of Pt is too small, insufficient catalytic sites will result in poor peroxidase activity of the MoSe2@Pt nanosheets; if the mass percentage of Pt is too large, aggregation will occur on the surface of MoSe2, reducing the exposed catalytic sites and also leading to poor peroxidase activity of the MoSe2@Pt nanosheets.

[0021] The three-in-one multifunctional MoSe2@Pt nanosheets prepared by this invention possess excellent peroxidase activity, fluorescence quenching ability, and photothermal properties, simultaneously providing catalytic colorimetric, fluorescence, and photothermal signals. Furthermore, their high specific surface area and ultrathin nature facilitate protein adsorption and probe flow, further enhancing detection sensitivity. The three-in-one multifunctional MoSe2@Pt nanosheets obtained through the preparation method provided by this invention can be applied to the highly sensitive three-modal immunochromatographic detection of RSV (Reactive Virus) using catalytic colorimetry, fluorescence, and photothermal methods.

[0022] The following exemplarily describes a method for preparing the three-in-one multifunctional MoSe2@Pt nanosheets provided by the present invention. The method for preparing the three-in-one multifunctional MoSe2@Pt nanosheets may include the following steps: S1. Molybdenum selenide powder was dissolved in chitosan aqueous solution to form a mixed solution and then ultrasonically crushed. The product was collected to obtain MoSe2 nanosheets. S2. Dissolve the MoSe2 nanosheets in deionized water, add Pt solution and stir. After centrifugation and washing, obtain the three-in-one multifunctional MoSe2@Pt nanosheets.

[0023] In some embodiments, the concentration of the chitosan aqueous solution can be 0.2-1.5 mg / mL, preferably 0.8 mg / mL; the concentration of MoSe2 in the mixed solution can be controlled at 10-20 mg / mL. The chitosan aqueous solution provides good dispersibility and stability to MoSe2, preventing sedimentation. When the concentration of the chitosan aqueous solution is too low, it has almost no effect on improving the dispersibility of MoSe2; when the concentration of the chitosan aqueous solution is too high, the dispersibility of MoSe2 is not further improved. Furthermore, the concentration of MoSe2 has a significant impact on the yield and ultrasonic effect. When the concentration of MoSe2 is too low, the product yield is extremely low, which is not conducive to practical applications; when the concentration of MoSe2 is too high, incomplete ultrasonication occurs, resulting in nanosheets with larger sizes and thicknesses.

[0024] In some embodiments, the ultrasonic breaking power can be 500W, and the ultrasonic breaking time can be 6 to 15 hours, in order to obtain ultrathin nanosheets.

[0025] In some embodiments, the product collection method may be as follows: first, centrifuge at a rate of 2000-5000 r / min (e.g., 3000 r / min) to collect the supernatant, then centrifuge again at a rate of 6000-10000 r / min (e.g., 8000 r / min) to collect the precipitate, and wash the precipitate alternately with ethanol and deionized water to obtain the MoSe2 nanosheets.

[0026] In some embodiments, the diameter of the MoSe2 nanosheets can be 150–200 nm, and the thickness can be 2–5 nm. If the diameter and thickness of the MoSe2 nanosheets are too large, membrane jamming may occur in subsequent immunochromatographic experiments; if the diameter and thickness of the MoSe2 nanosheets are too small, the surface area and specific surface area of ​​the material will be small, which is not conducive to the adsorption of antibodies and proteins, and both will affect the final detection sensitivity.

[0027] In some embodiments, the Pt solution may be an aqueous solution of Pt particles.

[0028] In some embodiments, the mass ratio of the MoSe2 nanosheets to Pt can be controlled to be 1:(0.1 to 0.3).

[0029] In some embodiments, the centrifugation speed in S2 can be 6000-10000 r / min, preferably 8000 r / min, and the centrifugation time can be 20 min.

[0030] The following exemplifies the application of the three-in-one multifunctional MoSe2@Pt nanosheets provided by the present invention in highly sensitive three-modal immunochromatographic detection of RSV for non-disease diagnosis and treatment purposes, using colorimetric-fluorescence-photothermal methods. The application of immunochromatographic detection may include the following steps: First, the above-mentioned three-in-one multifunctional MoSe2@Pt nanosheets were dissolved in a buffer solution, then RSV-labeled antibodies were added, and the nanosheets were blocked with bovine serum albumin (BSA). The three-in-one multifunctional MoSe2@Pt immunoprobe for RSV detection was obtained by electrostatic adsorption. Then, the RSV virus solution to be tested was mixed with the three-in-one multifunctional MoSe2@Pt immunoprobe and placed in a multi-well plate. The lateral flow immunochromatography (LFIA) test strip for RSV multimodal detection was inserted into the well for chromatography. After chromatography, the peroxidase catalytic performance, fluorescence quenching performance and photothermal conversion performance of the three-in-one multifunctional MoSe2@Pt nanosheets were utilized. Combined with a smartphone, portable spectrometer and handheld infrared thermal imager, the changes in colorimetric, fluorescence and temperature signals on the T line of the test strip were recorded in real time to complete the highly sensitive immunochromatographic detection of RSV virus in three modalities: catalytic colorimetric-fluorescence-photothermal.

[0031] In some embodiments, the mass ratio of RSV-labeled antibody to the three-in-one multifunctional MoSe2@Pt nanosheets can be (0.01-0.05):1, and the mass ratio of RSV-labeled antibody to BSA can be (0.3-1.7):1. Immunoprobes prepared within this range exhibit excellent detection sensitivity. Below this range, insufficient sensitivity may occur due to incomplete virus capture; above this range, non-specific adsorption may occur, resulting in false positive signals during detection.

[0032] In some embodiments, the lateral flow immunochromatographic (LFIA) test strip for RSV multimodal detection may include: a PVC base plate, and a sample pad, a nitrocellulose membrane, and an absorbent pad sequentially disposed adjacent to the PVC base plate, wherein a detection line (T line) and a control line (C line) are provided on the nitrocellulose membrane; preferably, the interface between the sample pad and the nitrocellulose membrane overlaps by 2 mm, and the interface between the nitrocellulose membrane and the absorbent pad overlaps by 2 mm.

[0033] In some embodiments, the T line is coated with an RSV-coated antibody modified with CdSe / ZnS quantum dots, and the C line is coated with a goat anti-mouse IgG antibody; the streaking rates of the T line and the C line can be 0.8 mg / mL and 1 mg / mL, respectively.

[0034] As an example, the preparation process of the CdSe / ZnS quantum dot-modified RSV-coated antibody may include the following steps: (1) Collect 1 mL of 100 nM CdSe / ZnS quantum dots by centrifugation and disperse them in 1 mL of MES buffer solution to obtain solution A; (2) Add 5 μL of 100 mM EDC and 10 μL of 100 mM NHS solution to the above solution A, and activate it by sonication for 15 min to obtain solution B; (3) Add 80-200 μg of RSV-coated antibody to solution B, shake at room temperature for 1-2 h, and add 5-10 μg of BSA for blocking for 30 min; (4) The product was collected by centrifugation at 15000 r / min and dispersed in 50 μL of PBS solution containing 2% trehalose to obtain the CdSe / ZnS quantum dot modified RSV coated antibody.

[0035] The three-in-one multifunctional MoSe2@Pt nanosheets prepared using the method provided in this invention can achieve a detection limit of 0.05 ng / mL for RSV virus, which is 100 times higher than the detection sensitivity of traditional colloidal gold, and is expected to realize highly sensitive and rapid home self-testing for RSV.

[0036] This invention selects MoSe2, which possesses high specific surface area, excellent photothermal properties, and good biocompatibility, as the research object. Two-dimensional ultrathin MoSe2 nanosheets were prepared by ultrasonic exfoliation, and then modified with Pt particles to successfully prepare MoSe2@Pt nanosheets with excellent peroxidase activity, fluorescence quenching ability, and photothermal properties. Furthermore, these nanosheets were applied to immunochromatographic detection, achieving highly sensitive detection of RSV using a three-modal approach: catalytic colorimetry, fluorescence, and photothermal detection. Compared with traditional colloidal gold technology, the sensitivity of the catalytic colorimetric, fluorescence, and photothermal detection modes was improved by 5 times, 10 times, and 100 times, respectively. Moreover, all three detection modes can be completed within 20 minutes. Compared with single-modal detection technology, multimodal detection technology greatly improves the accuracy, reliability, and flexibility of detection.

[0037] The following examples further illustrate the present invention in detail. It should also be understood that the following examples are only for further explanation of the present invention and should not be construed as limiting the scope of protection of the present invention. Any non-essential improvements and adjustments made by those skilled in the art based on the above description of the present invention are within the scope of protection of the present invention. The specific process parameters, etc., in the following examples are merely examples within a suitable range; that is, those skilled in the art can make appropriate selections within the range based on the description herein, and are not intended to be limited to the specific values ​​in the examples below. Unless otherwise specified, the technical means used in the examples are conventional means well known to those skilled in the art.

[0038] Example 1

[0039] 1. Preparation of three-in-one multifunctional MoSe2@Pt nanosheets. MoSe2 was used as the raw material, and chitosan aqueous solution was used as the solvent. The mixture was ultrasonically disrupted for 6 hours by controlling the concentration of MoSe2 to be 10 mg / mL and the concentration of chitosan aqueous solution to be 0.8 mg / mL. The supernatant was collected by centrifugation at 3000 rpm, followed by centrifugation at 8000 rpm and washing with alternating ethanol and deionized water to obtain MoSe2 nanosheets. The obtained MoSe2 nanosheets were dissolved in deionized water, and Pt solution was added and stirred, controlling the mass ratio of Pt to MoSe2 to be 0.1:1. The precipitated MoSe2@Pt was collected by centrifugation and repeatedly washed with deionized water and ethanol to obtain three-in-one multifunctional MoSe2@Pt nanosheets for later use. 2. Preparation of a three-in-one multifunctional MoSe2@Pt immunoprobe for RSV detection. 1 mg of the three-in-one multifunctional MoSe2@Pt nanosheets were dissolved in PBST buffer, 10 μg of RSV-labeled antibody was added, and the mixture was blocked with 10 μg of BSA. The three-in-one multifunctional MoSe2@Pt immunoprobe for RSV detection was obtained by electrostatic adsorption. 3. Preparation of lateral flow immunochromatographic (LFIA) test strips for RSV multimodal detection. The lateral flow immunochromatographic (LFIA) test strip for RSV multimodal detection consists of four parts: a PVC plate, a nitrocellulose membrane, an absorbent pad, and a sample pad. The sample pad and the nitrocellulose membrane overlap by 2 mm, and the nitrocellulose membrane and the absorbent pad overlap by 2 mm. A detection line (T line) and a control line (C line) are set on the nitrocellulose membrane. The T line is coated with an RSV-coated antibody modified with CdSe / ZnS quantum dots, and the C line is coated with goat anti-mouse IgG antibody. The streak rates are 0.8 mg / mL and 1 mg / mL, respectively. The preparation steps of the CdSe / ZnS quantum dot-modified RSV-coated antibody coated on the T line include: (1) Collect 1 mL of 100 nM CdSe / ZnS quantum dots by centrifugation and disperse them in 1 mL of MES buffer solution to obtain solution A; (2) Add 5 μL of 100 mM EDC and 10 μL of 100 mM NHS solution to the above solution A, and activate by sonication for 15 min to obtain solution B; (3) Add 80 μg of RSV-coated antibody to solution B, shake at room temperature for 2 h, and add 5 μg of BSA for blocking for 30 min; (4) The product was collected by centrifugation at 15000 r / min and dispersed in 50 μL of PBS solution containing 2% trehalose to obtain the CdSe / ZnS quantum dot modified RSV coated antibody. 4. Using the aforementioned three-in-one multifunctional MoSe2@Pt nanosheets for non-disease diagnosis and treatment purposes, RSV catalytic colorimetric-fluorescence-photothermal three-modal high-sensitivity immunochromatographic detection is performed. Different concentrations of RSV virus were mixed with a three-in-one multifunctional MoSe2@Pt immunoprobe and placed in a 96-well plate. The test strip was inserted into the well for chromatography. After chromatography, the T line and C line of the test strip were observed. The appearance of the C line indicated that the test strip was working properly, and the signal on the T line could then be read. Because the probe used has excellent peroxidase activity, adding a H2O2 / TMB mixed solution to the T line of the test strip can make the T line appear blue, thereby amplifying the colorimetric signal. Utilizing the probe's excellent fluorescence quenching ability, detection can be performed by observing the change in fluorescence intensity of the T line under 365nm ultraviolet light. At the same time, utilizing the probe's photothermal activity, the temperature signal on the T line at different RSV concentrations can be recorded with a handheld infrared thermal imager for highly sensitive detection.

[0040] Figure 1 The image shows the XRD pattern of the three-in-one multifunctional MoSe2@Pt nanosheets prepared in Example 1 of this invention. As can be seen from the image, the MoSe2@Pt composite contains not only the diffraction peaks of the main component MoSe2, but also the diffraction peaks of Pt. However, due to the low Pt content, the diffraction peaks are weaker. These results indicate the successful preparation of MoSe2@Pt.

[0041] Figure 2 This is a TEM image of the three-in-one multifunctional MoSe2@Pt nanosheets prepared in Example 1 of this invention. As can be seen from the image, the prepared MoSe2@Pt composite has a sheet-like structure, with Pt particles uniformly loaded on the surface of the MoSe2 nanosheets, and the diameter of the nanosheets is 150-200 nm.

[0042] Figure 3 The image shows the EDS spectrum of the three-in-one multifunctional MoSe2@Pt nanosheets prepared in Example 1 of this invention. As can be seen from the image, Mo, Se, and Pt elements are uniformly distributed.

[0043] Example 2

[0044] Referring to Example 1, the main difference is: In step 1, the concentration of MoSe2 was controlled at 15 mg / mL, the crushing time was 8 h, and the mass ratio of Pt to MoSe2 was controlled at 0.2:1. In step 2, 20 μg of RSV-labeled antibody was added, and the mixture was blocked with 20 μg of BSA. In step 3, in the preparation step (3) of the CdSe / ZnS quantum dot modified RSV coated antibody coated on the T line, 150 μg of RSV coated antibody is added to solution B.

[0045] Figure 4 The figure shows the enzyme catalytic performance of the three-in-one multifunctional MoSe2@Pt nanosheets prepared in Example 2 of this invention. As can be seen from the figure, the MoSe2@Pt nanosheets exhibit significantly enhanced absorption at 652 nm, indicating that the MoSe2@Pt nanosheets possess excellent peroxidase activity.

[0046] Figure 5 The figure shows the photothermal performance of the three-in-one multifunctional MoSe2@Pt nanosheets prepared in Example 2 of this invention. As can be seen from the figure, under irradiation by an 808nm laser, the temperature of the MoSe2@Pt nanosheet aqueous solution rises by approximately 45°C within 6 minutes, while the temperature of pure water changes by only about 2°C under the same conditions, indicating that the MoSe2@Pt nanosheets possess excellent photothermal properties.

[0047] Figure 6 The images show the immunoassay performance of the three-in-one multifunctional MoSe2@Pt nanosheets prepared in Example 2 of this invention. (a) shows the immunochromatographic results of RSV at concentrations of 0-100 ng / mL; (b) shows the signal amplification results of the chromatographic colorimetric results using enzyme catalysis; (c) shows the fluorescence effect of the T-line on test strips with different concentrations of RSV; and (d) shows the photothermal effect of the T-line on test strips with different concentrations of RSV. As can be seen from the images, the visual detection limit is 5 ng / mL, the catalytic detection limit is 0.5 ng / mL, and the photothermal detection limit is 0.05 ng / mL.

[0048] Example 3

[0049] Referring to Example 1, the main difference is: In step 1, the concentration of MoSe2 is controlled at 20 mg / mL, the crushing time is 10 h, and the mass ratio of Pt to MoSe2 is controlled at 0.3:1. In step 2, 30 μg of RSV-labeled antibody was added, and the mixture was blocked with 25 μg of BSA. In step 3, the preparation step (3) of the CdSe / ZnS quantum dot modified RSV coated antibody coated on the T line involves adding 100 μg of RSV coated antibody to solution B, shaking at room temperature for 1.5 h, and adding 8 μg of BSA for blocking.

[0050] Example 4

[0051] Referring to Example 1, the main difference is: In step 1, the concentration of MoSe2 is controlled at 15 mg / mL, the crushing time is 15 h, and the mass ratio of Pt to MoSe2 is controlled at 0.2:1. In step 2, 20 μg of RSV-labeled antibody was added, and the mixture was blocked with 20 μg of BSA. In step 3, in the preparation step (3) of the CdSe / ZnS quantum dot modified RSV coated antibody coated on the T line, 150 μg of RSV coated antibody is added to solution B.

[0052] Example 5

[0053] Referring to Example 1, the main difference is: In step 1, the concentration of MoSe2 is controlled at 20 mg / mL, the crushing time is 10 h, and the mass ratio of Pt to MoSe2 is controlled at 0.3:1. In step 2, 50 μg of RSV-labeled antibody was added, and the mixture was blocked with 30 μg of BSA. In step 3, the preparation of the CdSe / ZnS quantum dot modified RSV coated antibody coated on the T line is as follows: 200 μg of RSV coated antibody is added to solution B, shaken at room temperature for 1.5 h, and 10 μg of BSA is added for blocking.

[0054] Comparative Example 1

[0055] Referring to Example 2, the main difference is that RSV samples of different concentrations are dropped onto colloidal gold test strips for detection.

[0056] Figure 7 The graph shows the detection performance of the commercial colloidal gold test strip in Comparative Example 1 for RSV. As can be seen from the graph, the visual detection limit is 5 ng / mL.

[0057] Comparative Example 2

[0058] Referring to Example 2, the main difference is that the mass ratio of Pt to MoSe2 is controlled to be 0.8:1.

[0059] The test results show that the nanosheets prepared in Comparative Example 2 have a visual colorimetric detection limit of 5 ng / mL, a catalytic colorimetric detection limit of 1 ng / mL, and a photothermal detection limit of 0.1 ng / mL for RSV.

[0060] Comparative Example 3

[0061] Referring to Example 2, the main difference is that in step 2, 20 μg of RSV-labeled antibody is added and blocked with 10 μg of BSA.

[0062] The test results show that the nanosheets prepared in Comparative Example 3 have a visual colorimetric detection limit of 1 ng / mL for RSV, a catalytic colorimetric detection limit of 1 ng / mL, and a photothermal detection limit of 0.5 ng / mL.

[0063] Comparative Example 4

[0064] Referring to Example 2, the main difference is that in step 3, in the preparation step (3) of the RSV-coated antibody modified by CdSe / ZnS quantum dots coated on the T line, 300 μg of RSV-coated antibody is added to solution B.

[0065] The test results show that the nanosheets prepared in Comparative Example 3 have a visual colorimetric detection limit of 1 ng / mL for RSV, a catalytic colorimetric detection limit of 1 ng / mL, and a photothermal detection limit of 0.5 ng / mL.

[0066] Although the present invention has been described in detail through the preferred embodiments above, it should be understood that the above description should not be considered as a limitation of the present invention. Various modifications and substitutions to the present invention will be apparent to those skilled in the art after reading the above description. Therefore, the scope of protection of the present invention should be defined by the appended claims.

Claims

1. An application of a catalytic colorimetric-fluorescence-photothermal multimodal MoSe2@Pt immunoprobe for RSV virus detection, characterized in that, The MoSe2@Pt immunoprobe is formed by electrostatic adsorption of MoSe2@Pt nanosheets, RSV-labeled antibody, and bovine serum albumin. The MoSe2@Pt nanosheets simultaneously possess peroxidase catalytic properties, fluorescence quenching properties, and photothermal properties. The MoSe2@Pt nanosheets have a sheet-like structure with a diameter of 150-200 nm, a thickness of 2-5 nm, and a surface area / volume ratio of 0.21-0.51 nm. -1 ; The preparation method of the MoSe2@Pt nanosheets includes the following steps: S1. Molybdenum selenide powder was dissolved in chitosan aqueous solution to form a mixed solution and then ultrasonically crushed. The product was collected to obtain MoSe2 nanosheets. S2. Dissolve the MoSe2 nanosheets in deionized water, add Pt solution and stir. After centrifugation and washing, obtain the MoSe2@Pt nanosheets.

2. The application according to claim 1, characterized in that, Based on the total mass of the MoSe2@Pt nanosheets being 100%, the mass percentage of MoSe2 is 70-90%, and the mass percentage of Pt is 10-30%.

3. The application according to claim 1, characterized in that, The concentration of the chitosan aqueous solution is 0.2-1.5 mg / mL; the concentration of MoSe2 in the mixed solution is 10-20 mg / mL. The ultrasonic fragmentation power is 500 W, and the ultrasonic fragmentation time is 6 to 15 hours.

4. The application according to claim 1, characterized in that, The method for collecting the product is as follows: first, centrifuge at a rate of 2000-5000 r / min to collect the supernatant, then centrifuge again at a rate of 6000-10000 r / min to collect the precipitate, and wash the precipitate alternately with ethanol and deionized water to obtain the MoSe2 nanosheets. The mass ratio of MoSe2 nanosheets to Pt is 1:(0.1~0.3).

Images