Virus detection optical fiber sensor and preparation method and application thereof

Abstract

The invention belongs to the technical field of biochemical optical fiber sensing, and particularly relates to a virus detection optical fiber sensor and a preparation method and application thereof. The virus detection optical fiber sensor comprises a broadband light source, an optical fiber circulator, a functional micro optical fiber structure and a spectrum analyzer; the broadband light source, the functional micro optical fiber structure and the spectrum analyzer are respectively connected with three ports of the optical fiber circulator; the functionalized micro-optical fiber structure comprises a micro-optical fiber structure with a hydrophobic protein film deposited on the surface and a biotin-modified DNA aptamer, and the biotin-modified DNA aptamer is adsorbed on the hydrophobic protein film on the surface of the micro-optical fiber structure through streptavidin. When the functionalized micro-optical fiber structure is inserted into a sample to be detected, the virus is specifically combined with the DNA aptamer, so that the effective refractive index of the end face of the functionalized micro-optical fiber structure is changed, the resonant wavelength of a reflection spectrum drifts, and then the virus concentration is detected. When the sensor is used for virus detection, the operation is simple, the detection is quick, and the specificity is strong.

Description

Technical Field

[0001] The present invention belongs to the technical field of biochemical optical fiber sensing, and in particular relates to an optical fiber sensor for virus detection, a preparation method thereof, and an application thereof. Background Art

[0002] Viruses, such as influenza and coronavirus, are the root causes of many infectious diseases. They can easily infect people and cause related illnesses, posing a serious threat to human health. Viruses can come from a wide range of sources, including water, food, and air.

[0003] Currently, viral detection methods primarily include real-time fluorescence quantitative PCR (polymerase chain reaction), genetic testing, and immunoassays. However, genetic testing and immunoassays are complex and time-consuming, requiring 1 to 8 hours. PCR, on the other hand, carries a high risk of contamination and poor specificity, making it prone to false positives. Therefore, there is an urgent need to develop a rapid and highly specific viral detection method to enable early diagnosis of the disease, establish an effective monitoring system, implement timely preventive measures, improve public health protection, and reduce the impact of viruses on human health. Summary of the Invention

[0004] In view of this, the object of the present invention is to provide a virus detection optical fiber sensor and its preparation method and application. The virus detection optical fiber sensor of the present invention has rapid detection, good specificity and accurate detection results.

[0005] The present invention provides a virus detection optical fiber sensor, comprising a broadband light source, an optical fiber circulator, a functionalized micro-optical fiber structure, and a spectrum analyzer;

[0006] The broadband light source, the functionalized micro-fiber structure, and the spectrum analyzer are respectively connected to the three ports of the optical fiber circulator;

[0007] The functionalized micro-fiber structure comprises a micro-fiber structure with a hydrophobin film deposited on the surface and a biotin-modified DNA aptamer. The biotin-modified DNA aptamer is adsorbed on the hydrophobin film on the surface of the micro-fiber structure through streptavidin.

[0008] Preferably, the micro-fiber structure includes an introduced single-mode fiber, a C-type fiber, and a single-mode fiber connected in sequence, and the micro-fiber structure is a Fabry-Perot interference structure.

[0009] Preferably, the micro-fiber structure includes the following three end faces: a first end face where the single-mode fiber is connected to the C-type fiber, a second end face where the single-mode fiber is connected to the C-type fiber, and a third end face on the other side of the single-mode fiber.

[0010] Preferably, the introduced single-mode optical fiber and the single-mode optical fiber are Corning SMF-28, with a refractive index of 1.444 at 1550 nm, a cladding diameter of 125 μm, and a core diameter of 8.2 μm.

[0011] Preferably, the C-type optical fiber is formed by side-throwing a hollow optical fiber with an outer diameter of 125 μm and an inner diameter of 50 μm.

[0012] The present invention also provides a method for preparing the virus detection optical fiber sensor described in the above technical solution, comprising the following steps:

[0013] The microfiber structure is sequentially immersed in a hydrophobin solution, a streptavidin solution, and a biotin-modified DNA aptamer solution to obtain a functionalized microfiber structure.

[0014] The functionalized micro-fiber structure, broadband light source and spectrum analyzer are respectively connected to the three ports of the optical fiber circulator to obtain a virus detection optical fiber sensor.

[0015] Preferably, the hydrophobin in the hydrophobin solution includes type I hydrophobin; the concentration of the hydrophobin solution is 100 to 300 μg / mL, and the first immersion time is 20 to 40 minutes.

[0016] Preferably, the concentration of the streptavidin solution is 25 to 75 μg / mL, and the second immersion time is 20 to 40 minutes.

[0017] Preferably, the concentration of the biotin-modified DNA aptamer solution is 5-10 μg / mL, the temperature of the third immersion is 2-6° C., and the time is 1-3 hours.

[0018] The present invention also provides the use of the virus detection optical fiber sensor described in the above technical solution or the virus detection optical fiber sensor obtained by the preparation method described in the above technical solution in virus detection for non-disease diagnosis and treatment purposes.

[0019] Compared with the prior art, the present invention has the following beneficial effects:

[0020] The present invention provides a virus detection optical fiber sensor, comprising a broadband light source, an optical fiber circulator, a functionalized micro-optical fiber structure, and a spectrum analyzer; the broadband light source, the functionalized micro-optical fiber structure, and the spectrum analyzer are respectively connected to three ports of the optical fiber circulator; the functionalized micro-optical fiber structure comprises a micro-optical fiber structure with a hydrophobin film deposited on the surface and a biotin-modified DNA aptamer; the biotin-modified DNA aptamer is adsorbed on the hydrophobin film on the surface of the micro-optical fiber structure via streptavidin.

[0021] The present invention utilizes DNA aptamers modified with hydrophobin, streptavidin, and biotin to functionalize a microfiber structure. The DNA aptamers specifically bind to viruses, altering the resonant wavelength of the functionalized microfiber structure and enabling highly sensitive and specific viral sensing. The virus-detecting fiber optic sensor of the present invention effectively improves the specificity of virus detection and can complete virus detection within 30 minutes, significantly shortening detection time.

[0022] Furthermore, the present invention utilizes C-shaped optical fibers to construct a highly sensitive microfiber structure with a vernier effect. This structure is compact, integrated, and capable of in-situ detection. The present invention utilizes an end-face-reflective microfiber structure, effectively increasing the area of ​​interaction between light and matter, thereby enhancing the sensitivity of virus detection. Using the sensor of the present invention for virus detection offers the advantages of simple operation, rapid detection, and high specificity, providing a novel approach for virus detection. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the following briefly introduces the drawings required for use in the embodiments. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.

[0024] Figure 1 Schematic diagram of the structure of the virus detection optical fiber sensor of the present invention, wherein 11 is a spectrum analyzer, 12 is a broadband light source, 13 is an optical fiber circulator, 14 is a micro-fiber structure, and 15 is an end face of a C-type optical fiber in the micro-fiber structure;

[0025] Figure 2 Schematic diagram of the micro-fiber structure in the virus detection optical fiber sensor of the present invention, wherein 21 is an introduction single-mode optical fiber, 22 is a C-type optical fiber, and 23 is a single-mode optical fiber;

[0026] Figure 3 This is a flow chart of the functionalization of the micro-fiber structure in the virus detection fiber optic sensor of the present invention;

[0027] Figure 4 This is a graph showing changes in the resonance peak of the reflection spectrum in deionized water after different concentrations of viruses bind to the DNA aptamer in Example 1;

[0028] Figure 5 The figure is the fitting curve of the resonance peak of the reflection spectrum of different concentrations of virus in Example 1. DETAILED DESCRIPTION

[0029] The present invention provides a virus detection optical fiber sensor, comprising a broadband light source, an optical fiber circulator, a functionalized micro-optical fiber structure, and a spectrum analyzer;

[0030] The broadband light source, the functionalized micro-fiber structure, and the spectrum analyzer are respectively connected to the three ports of the optical fiber circulator;

[0031] The functionalized micro-fiber structure comprises a micro-fiber structure with a hydrophobin film deposited on the surface and a biotin-modified DNA aptamer. The biotin-modified DNA aptamer is adsorbed on the hydrophobin film on the surface of the micro-fiber structure through streptavidin.

[0032] In the present invention, unless otherwise specified, the materials and equipment used are commercially available products in the art.

[0033] Figure 1 This is a schematic diagram of the structure of the virus detection fiber optic sensor of the present invention, which includes a spectrum analyzer 11, a broadband light source 12, a fiber circulator 13, and a functionalized micro-fiber structure 14. The optical signal emitted by the broadband light source 12 is input into port 1 of the fiber circulator 13. The optical signal is transmitted to the functionalized micro-fiber structure 14 through port 2 of the fiber circulator. The reflected light signal returned from the functionalized micro-fiber structure 14 is output through port 3 of the fiber circulator 13 and transmitted to the spectrum analyzer 11 for analysis of changes in the interference spectrum.

[0034] In the present invention, the wavelength band of the broadband light source is preferably 1250 to 1640 nm.

[0035] In the present invention, the optical fiber circulator includes three ports, which are mainly used for directional transmission of optical signals and processing of reflected signals.

[0036] In the present invention, the micro-fiber structure includes an introduced single-mode fiber, a C-type fiber, and a single-mode fiber connected in sequence, and the micro-fiber structure is a Fabry-Perot interferometer (FPI) structure;

[0037] The micro-fiber structure preferably includes the following three end faces: a first end face where the single-mode fiber is introduced into the connection between the single-mode fiber and the C-type fiber, a second end face where the single-mode fiber is connected to the C-type fiber, and a third end face on the other side of the single-mode fiber;

[0038] The introduced single-mode fiber and single-mode fiber are preferably Corning SMF-28, with a refractive index of 1.444 at 1550 nm, a cladding diameter of 125 μm, and a core diameter of 8.2 μm. The C-type fiber is preferably formed by side-polishing a hollow-core fiber with an outer diameter of 125 μm and an inner diameter of 50 μm, preferably using a grinding wheel, until the hollow core is exposed. The length of both the C-type fiber and the single-mode fiber is preferably 200 μm.

[0039] The introduced single-mode optical fiber, the C-type optical fiber and the single-mode optical fiber are preferably welded by an optical fiber fusion splicer, and the optical fiber fusion splicer is preferably Furukawa, S178A, Japan.

[0040] Figure 2 The schematic diagram of the micro-fiber structure of the present invention includes the introduction of a single-mode fiber 21, a C-type fiber 22, and a single-mode fiber 23, wherein the end face of the C-type fiber 22 is as shown in FIG. Figure 1 As shown in 15 in . Three reflectors are formed, namely the end face M1 for introducing the single-mode optical fiber 21, the left end face M2 and the right end face M3 of the single-mode optical fiber 23. The refractive index sensing sensitivity of the micro-fiber structure can be higher than 8000nm / RIU. The use of an end-face reflective micro-fiber structure can effectively increase the area of ​​interaction between light and matter and improve the ability to detect viruses. When the functionalized micro-fiber structure is inserted into the sample to be tested, the virus specifically binds to the DNA aptamer, causing the effective refractive index of the end faces M1, M2, and M3 to change, and thus the resonant wavelength of the reflection spectrum will drift.

[0041] In the functionalized micro-fiber structure, a single-mode optical fiber is introduced and hydrophobic protein is deposited on the end face of the single-mode optical fiber. A DNA aptamer that specifically recognizes the virus is attached. The virus specifically binds to the DNA aptamer, and the concentration of the virus is detected by changing the effective refractive index of the end face of the functionalized micro-fiber structure.

[0042] The present invention also provides a method for preparing the virus detection optical fiber sensor described in the above technical solution, comprising the following steps:

[0043] The microfiber structure is sequentially immersed in a hydrophobin solution, a streptavidin solution, and a biotin-modified DNA aptamer solution to obtain a functionalized microfiber structure.

[0044] The functionalized micro-fiber structure, broadband light source and spectrum analyzer are respectively connected to the three ports of the optical fiber circulator to obtain a virus detection optical fiber sensor.

[0045] The present invention sequentially immerses the micro-fiber structure in a hydrophobin solution, a streptavidin solution, and a biotin-modified DNA aptamer solution to obtain a functionalized micro-fiber structure.

[0046] In the present invention, the first soaking preferably further includes: washing the micro-fiber structure; the washing agent is preferably deionized water.

[0047] In the present invention, the hydrophobin in the hydrophobin solution preferably comprises type I hydrophobin, the solvent of the hydrophobin solution is preferably PBS buffer, and the pH value of the PBS buffer is preferably 7.4. The protein film formed by the self-assembly of the hydrophobin in the present invention is highly insoluble.

[0048] In the present invention, the concentration of the hydrophobin solution is preferably 100-300 μg / mL, and the first immersion time is preferably 20-40 minutes, specifically 30 minutes. After the first immersion, a hydrophobin film is formed on the surface of the micro-fiber structure, which is a nano-scale thin film.

[0049] In the present invention, after the first soaking, the method preferably further comprises: washing the obtained micro-optical fiber structure with the hydrophobin film deposited on the surface; the washing reagent is preferably deionized water.

[0050] In the present invention, the concentration of the streptavidin solution is preferably 25 to 75 μg / mL, specifically 25 μg / mL, 50 μg / mL, or 75 μg / mL. The second soaking time is preferably 20 to 40 minutes, specifically 30 minutes. The solvent of the streptavidin solution is preferably PBS buffer, and the pH value of the PBS buffer is preferably 7.4. After the second soaking, streptavidin is adsorbed on the surface of the hydrophobin membrane, and the hydrophobin membrane and streptavidin are non-covalently bound.

[0051] In the present invention, the second soaking preferably further comprises: washing the micro-fiber structure with streptavidin adsorbed on the surface, and then soaking it in a bovine serum albumin (BSA) solution, and washing the micro-fiber structure with bovine serum albumin adsorbed on the surface. The mass fraction of the bovine serum albumin solution is preferably 1% to 3%, and the soaking time is preferably 20 to 40 minutes, specifically 30 minutes; the solvent of the bovine serum albumin solution is preferably PBS buffer, and the pH value of the PBS buffer is preferably 7.4. The role of soaking in the bovine serum albumin solution is to block the hydrophobic protein binding sites that are not adsorbed with streptavidin. The reagents for both washes are preferably deionized water.

[0052] In the present invention, the concentration of the biotin-modified DNA aptamer solution is preferably 5-10 μg / mL, more preferably 7.5 μg / mL; the temperature of the third soaking is preferably 2-6°C, specifically 4°C, and the duration is preferably 1-3 hours, specifically 2 hours; the solvent of the biotin-modified DNA aptamer solution is preferably PBS buffer, and the pH value of the PBS buffer is preferably 7.4. After the third soaking, streptavidin binds to the biotin-modified DNA aptamer, functionalizing the microfiber structure; the biotin-modified DNA aptamer in the functionalized microfiber structure can specifically recognize viruses.

[0053] In the present invention, the biotin-modified DNA aptamer in the biotin-modified DNA aptamer solution is preferably modified with biotin at the 5' end of the DNA aptamer sequence. Different types of viruses can be identified according to the DNA aptamer sequence. The viruses preferably include dengue virus, SARS coronavirus or influenza virus, and the influenza virus preferably includes influenza A virus.

[0054] The present invention constructs a DNA aptamer that specifically recognizes viruses on the end face of a micro-fiber structure, which can realize the specific recognition of viruses by an optical fiber sensor. Figure 3 This is a flow chart for functionalizing the microfiber structure in the present invention's virus detection fiber optic sensor. The method first allows hydrophobic proteins to self-assemble into a film, altering the hydrophilicity and hydrophobicity of the microfiber structure's surface, forming a dense protein nanofilm. Streptavidin is then adsorbed onto the surface of the hydrophobin film (a BSA solution can be used to block hydrophobin binding sites not adsorbed with streptavidin). Biotin binds to streptavidin with high affinity and specificity, allowing the biotin-modified DNA aptamer to be fixed to the end face of the microfiber structure.

[0055] After obtaining the functionalized micro-fiber structure, the present invention connects the functionalized micro-fiber structure, a broadband light source, and a spectrum analyzer to three ports of a fiber optic circulator to obtain a virus detection fiber optic sensor.

[0056] The present invention has no special requirements for the connection, and common methods used by those skilled in the art can be used.

[0057] The present invention also provides the use of the virus detection optical fiber sensor described in the above technical solution or the virus detection optical fiber sensor obtained by the preparation method described in the above technical solution in virus detection for non-disease diagnosis and treatment purposes.

[0058] In the present invention, the virus detection preferably includes dengue virus detection, SARS coronavirus detection or influenza virus detection.

[0059] The present invention sequentially deposits hydrophobin, streptavidin, and a biotin-modified DNA aptamer on the end faces M1, M2, and M3 (circular end faces) of the microfiber structure 14 to form a specific recognition membrane. The hydrophobin self-assembles into a membrane, altering the hydrophilicity and hydrophobicity of the microfiber structure 14's surface, forming a dense protein nanofilm. This protein membrane efficiently adsorbs biomolecules. Streptavidin is adsorbed onto the surface of the hydrophobin membrane. Due to the high affinity and specificity of biotin binding to streptavidin, the biotin-modified DNA aptamer is fixed to the end faces M1, M2, and M3 of the microfiber structure 14, thereby functionalizing the microfiber structure 14.

[0060] This invention inserts the functionalized microfiber structure into a sample to detect viruses in water. A broadband light source emits signal light, which is then introduced through single-mode fiber, C-type fiber, and single-mode fiber. Fresnel reflection occurs at the end face of the introduced single-mode fiber and at both ends of the single-mode fiber. The reflected signal is coupled to a spectrum analyzer via a fiber circulator. When viruses specifically bind to DNA aptamers, the effective refractive index of the microfiber structure's end face changes, shifting the resonant wavelength. This shift in wavelength allows the spectrometer to quantitatively determine the virus concentration.

[0061] The specific principles are as follows:

[0062] Light from the broadband light source 12 enters the functionalized microfiber structure 14 through the fiber circulator 13, forming three reflectors, namely the end face M1 of the introduced single-mode fiber 21, the left end face M2 of the single-mode fiber 23, and the right end face M3. The end face M1 of the introduced single-mode fiber 21 and the left end face M2 of the single-mode fiber 23 form a double-beam interference, denoted as FPI1. Similarly, the left end face M2 and the right end face M3 of the single-mode fiber 23 form a double-beam interference, denoted as FPI2. When the free spectral ranges of FPI1 and FPI2 are close, an optical vernier effect is generated, which can effectively improve the sensitivity of refractive index measurement, thereby improving the sensitivity of virus detection.

[0063] The reflected light intensity Ir can be expressed as:

[0064]

[0065] Among them A 2 、B 2 、C 2 Represent the reflected light intensity of M1, M2 and M3 respectively, Represent the phase offset of FPI1 and FPI2 respectively, and the formula is as follows:

[0066]

[0067] Where λ is the wavelength of the input light, L1 and L2 are the cavity lengths of FPI1 and FPI2 respectively, and Δn eff In order to detect the changes in the effective refractive index of the front and rear end faces M1, M2, and M3 of the virus, the virus content in the sample to be tested can be demodulated.

[0068] To further illustrate the present invention, the virus detection optical fiber sensor provided by the present invention, its preparation method and application are described in detail below with reference to the accompanying drawings and examples, but they should not be construed as limiting the scope of protection of the present invention.

[0069] Example 1 Dengue virus detection:

[0070] according to Figure 1The structure diagram of the virus detection fiber optic sensor is assembled, including a spectrum analyzer 11, a broadband light source 12, a fiber circulator 13, and a functionalized micro-fiber structure 14. The broadband light source 12 emits light with a wavelength of 1250 to 1640 nm into the functionalized micro-fiber structure 14. The micro-fiber structure 14 detects changes in the external environment by measuring changes in the interference signal. Since the surface of the functionalized micro-fiber structure 14 has a DNA aptamer that specifically recognizes viruses, during the binding process between the virus and the DNA aptamer, the end faces M1, M2, and M3 ( Figure 2 ) changes, and the virus concentration information in the sample is demodulated in the spectrum analyzer 11.

[0071] (1) Use deionized water to clean the micro-fiber structure, Figure 2 The schematic diagram of the micro-fiber structure is a Fabry-Perot type fiber interference structure. Single-mode fiber 21, C-type fiber 22, and single-mode fiber 23 are introduced and welded in sequence using a fiber fusion splicer (Furukawa, S178A, Japan). The C-type fiber 22 is polished by a hollow fiber grinding wheel, and the end face is as shown in FIG. Figure 1 15. The length of the C-type optical fiber 22 and the single-mode optical fiber 23 are both 200 μm, the cladding diameter of the single-mode optical fiber is 125 μm, and the core diameter is 8.2 μm.

[0072] (2) The microfiber structure was immersed in a PBS buffer solution containing 8 kDa hydrophobin (HGFⅠ) at a concentration of 300 μg / mL for 30 minutes. A nanoscale protein film was formed at the interface between the two phases of the microfiber structure by self-assembly.

[0073] (3) After cleaning with deionized water, the microfiber structure was immersed in a 25 μg / mL streptavidin PBS buffer solution for 30 min.

[0074] (4) After cleaning with deionized water, the microfiber structure was immersed in a bovine serum albumin (BSA) PBS buffer solution (concentration of 1 wt%) for 30 min to block the hydrophobic protein binding sites that were not adsorbed with streptavidin.

[0075] (5) After washing with deionized water, the microfiber structure was immersed in a PBS buffer solution of a modified biotin DNA aptamer with a concentration of 7.5 μg / mL at 4°C for 2 h. The DNA aptamer sequence is: 5'-biotin-ACTAGGTTGCAGGGGACTGCTCGGGATTGCGGATCAACCTAGTTG CTTCTCTCGTATGAT-3' (SEQ ID No. 1), which can specifically recognize the dengue virus marker NS1 protein.

[0076] (6) After washing with deionized water, the functionalized microfiber structure obtained in step (5) was inserted into a dengue virus marker NS1 protein solution with a concentration of 10 ng / mL for 30 min to allow it to fully bind to the DNA aptamer. It was then immersed in deionized water to record the reflection spectrum to ensure that the optical fiber sensor was in the same background refractive index environment.

[0077] (7) Repeat the above step (6) to measure dengue virus marker NS1 protein solutions with concentrations of 30 ng / mL and 50 ng / mL respectively.

[0078] Figure 4 The following is a graph showing the detection data of different concentrations of the dengue virus marker NS1 protein. The horizontal axis is the continuous sampling time in deionized water after the dengue virus marker NS1 protein fully binds to the DNA aptamer to ensure the same background refractive index; the vertical axis is the data plotted with the resonant wavelength of the reflectance spectrum envelope, which shows that the detection is stable. The standard curve obtained after fitting is as follows: Figure 5 As shown, the functional relationship of the standard curve is obtained according to the standard curve, y=0.158x+1549.36; the virus liquid to be tested is detected by the method of step (6), the resonant wavelength y' of the reflection spectrum envelope is measured, and y' is substituted into the functional relationship to obtain the concentration of the virus in the virus liquid to be tested.

[0079] The present invention provides a hydrophobin-functionalized virus detection fiber optic sensor. DNA aptamers are modified on a microfiber structure for virus detection. Streptavidin is bound to the surface of a self-assembled hydrophobin membrane on the fiber end face, followed by a biotin-modified DNA aptamer, to form a specific virus detection fiber optic biochemical sensor. The binding reaction between the virus and the DNA aptamer causes a change in the effective refractive index of the fiber end face, altering the resonant wavelength of the fiber optic sensor and thereby determining the virus concentration. This hydrophobin-functionalized virus detection fiber optic sensor meets the low detection limit requirements in environmental monitoring and medicine, and has potential applications.

[0080] Although the above embodiments provide a detailed description of the present invention, they are only part of the embodiments of the present invention, not all of the embodiments. People can also obtain other embodiments based on the embodiments of the present invention without creative work, and these embodiments all fall within the scope of protection of the present invention.

Claims

1. A virus detection optical fiber sensor, characterized in that: Including broadband light sources, fiber circulators, functionalized micro-fiber structures and spectrum analyzers; The broadband light source, the functionalized micro-fiber structure, and the spectrum analyzer are respectively connected to the three ports of the optical fiber circulator; The functionalized micro-fiber structure comprises a micro-fiber structure with a hydrophobin film deposited on the surface and a biotin-modified DNA aptamer. The biotin-modified DNA aptamer is adsorbed on the hydrophobin film on the surface of the micro-fiber structure through streptavidin.

2. The virus detection optical fiber sensor according to claim 1, characterized in that: The micro-fiber structure includes an introduction single-mode fiber, a C-type fiber, and a single-mode fiber connected in sequence, and the micro-fiber structure is a Fabry-Perot interference structure.

3. The virus detection optical fiber sensor according to claim 2, characterized in that: The micro-fiber structure includes the following three end faces: a first end face where the single-mode fiber is connected to the C-type fiber, a second end face where the single-mode fiber is connected to the C-type fiber, and a third end face on the other side of the single-mode fiber.

4. The virus detection optical fiber sensor according to claim 2 or 3, characterized in that: The introduced single-mode optical fiber and the single-mode optical fiber are Corning SMF-28, with a refractive index of 1.444 at 1550 nm, a cladding diameter of 125 μm, and a core diameter of 8.2 μm.

5. The virus detection optical fiber sensor according to claim 2 or 3, characterized in that: The C-type optical fiber is formed by side-throwing a hollow optical fiber with an outer diameter of 125 μm and an inner diameter of 50 μm.

6. The method for preparing the virus detection optical fiber sensor according to any one of claims 1 to 5, characterized in that: The following steps are involved: The microfiber structure is sequentially immersed in a hydrophobin solution, a streptavidin solution, and a biotin-modified DNA aptamer solution to obtain a functionalized microfiber structure. The functionalized micro-fiber structure, broadband light source and spectrum analyzer are respectively connected to the three ports of the optical fiber circulator to obtain a virus detection optical fiber sensor.

7. The preparation method according to claim 6, characterized in that The hydrophobin in the hydrophobin solution includes type I hydrophobin; the concentration of the hydrophobin solution is 100 to 300 μg / mL, and the first immersion time is 20 to 40 minutes.

8. The preparation method according to claim 6, characterized in that The concentration of the streptavidin solution is 25 to 75 μg / mL, and the second soaking time is 20 to 40 minutes.

9. The preparation method according to claim 6, characterized in that The concentration of the biotin-modified DNA aptamer solution is 5 to 10 μg / mL, the temperature of the third immersion is 2 to 6° C., and the time is 1 to 3 hours.

10. Use of the virus detection optical fiber sensor according to any one of claims 1 to 5 or the virus detection optical fiber sensor obtained by the preparation method according to any one of claims 6 to 9 in virus detection for non-disease diagnosis and treatment purposes.

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