An anti-interference LSPR optical fiber sensing probe and sample detection device

Abstract

The utility model discloses an anti -interference LSPR optical fiber sensing probe and sample detection device relates to optical fiber sensor technical field, including sensor joint, one end of sensor joint is used for connecting detection optical fiber, the other end of sensor joint is equipped with sensor outer tube and sensor capillary, sensor outer tube sets up in the outside of sensor capillary, be equipped with sample anti -interference layer on the outer wall of sensor capillary, be equipped with sample detection layer on the inner wall of sensor capillary, the one end of sensor capillary away from sensor joint is installed with mirror surface, the mirror surface can carry out the reflection to the light signal with detection information, the one end of sensor outer tube away from sensor joint is liquid inlet, be equipped with liquid outlet on the lateral wall of sensor joint. The utility model discloses be equipped with sample anti -interference layer, can effectively improve the measurement accuracy.

Description

Technical Field

[0001] This utility model relates to the field of fiber optic sensor technology, and in particular to an anti-interference LSPR fiber optic sensing probe and sample detection device. Background Technology

[0002] Surface plasmon resonance (SPR) sensors, an optical-based detection technology, achieve high-sensitivity detection by exciting electromagnetic waves at the metal-dielectric interface. This technology can monitor minute changes in the refractive index of a metal surface medium in real time, enabling precise analysis of parameters such as liquid composition, gas concentration, and biomolecular interactions. Compared to traditional sensing technologies, SPR sensors offer significant advantages in detection sensitivity, response speed, and stability, and have been widely applied in fields such as biomedicine and environmental monitoring.

[0003] Although prism-type SPR sensors have been commercialized abroad, their complex structure, large size, and high manufacturing cost limit their widespread adoption in industrial applications. In contrast, fiber optic sensors, with their miniaturization, flexibility, and resistance to electromagnetic interference, have become an important development direction for portable sensing technology. In recent years, localized surface plasmon resonance (LSPR) sensors based on gold nanobiconical structures have shown great potential in low-concentration detection due to their excellent temperature stability and ultra-high sensitivity, and have gradually become a research hotspot in the field of fiber optic sensing.

[0004] However, existing fiber optic LSPR sensors have limited detection accuracy due to their poor anti-interference capabilities.

[0005] Therefore, there is an urgent need in this field for a novel anti-interference LSPR fiber optic sensing probe and sample detection device to solve the above problems. Utility Model Content

[0006] The purpose of this invention is to provide an anti-interference LSPR fiber optic sensing probe and sample detection device to solve the problems existing in the prior art and achieve high detection accuracy.

[0007] To achieve the above objectives, this utility model provides the following solution:

[0008] This utility model discloses an anti-interference LSPR fiber optic sensing probe, including a sensor connector. One end of the sensor connector is used to connect to a detection fiber, and the other end of the sensor connector is provided with a sensor outer tube and a sensor capillary. The sensor outer tube is disposed outside the sensor capillary. A sample anti-interference layer is provided on the outer wall of the sensor capillary, and a sample detection layer is provided on the inner wall of the sensor capillary. A reflective mirror is installed at the end of the sensor capillary away from the sensor connector. The reflective mirror can reflect the light signal carrying detection information. The end of the sensor outer tube away from the sensor connector is a liquid inlet, and a liquid outlet is provided on the side wall of the sensor connector.

[0009] Preferably, the sample anti-interference layer comprises gold nanospheres; the sample detection layer comprises gold nanobipyramidal particles.

[0010] Preferably, the sensor capillary is a quartz capillary.

[0011] Preferably, the reflective mirror is a silver film with a thickness of 100 nm.

[0012] Preferably, the end faces of the detection optical fiber and the sensor capillary are both planar structures.

[0013] Preferably, the cross-sectional diameter of the detection optical fiber is larger than the cross-sectional diameter of the sensor capillary.

[0014] This utility model discloses a detection device, namely the above-mentioned anti-interference LSPR fiber optic sensing probe.

[0015] It also includes a light source generating device, an input optical fiber, an optical fiber coupler, an output optical fiber, and a signal analysis device. The light source generating device is connected to the first interface of the optical fiber coupler through the input optical fiber. The second interface of the optical fiber coupler is connected to the anti-interference LSPR optical fiber sensing probe. The third interface of the optical fiber coupler is connected to the signal analysis device through the output optical fiber.

[0016] Preferably, the light source generating device is a broadband light source.

[0017] Preferably, the signal analysis device is a fiber optic spectrometer.

[0018] Preferably, the signal analysis device is electrically connected to a computer.

[0019] The present invention achieves the following technical advantages over the prior art:

[0020] In this invention, a sample anti-interference layer is provided on the outer wall of the sensor capillary, and a sample detection layer is provided on the inner wall of the sensor capillary. The data information of the sample anti-interference layer is used to compensate and correct the interference data information detected by the sample detection layer, thereby improving the measurement accuracy of the device. Attached Figure Description

[0021] To more clearly illustrate the technical solutions in the embodiments of this utility model or the prior art, the drawings used in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this utility model. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0022] Figure 1 This is a schematic diagram of the anti-interference LSPR fiber optic sensing probe in Example 1;

[0023] Figure 2 This is a diagram showing the internal structure of the sensor outer tube in the anti-interference LSPR fiber optic sensing probe of Example 1;

[0024] Figure 3 This is a cross-sectional view of the anti-interference LSPR fiber optic sensing probe of Example 1;

[0025] Figure 4 This is a schematic diagram of the sample detection device in Example 2;

[0026] In the diagram: 1-Sensor connector; 2-Detection fiber optic cable; 3-Sensor outer tube; 4-Sensor capillary; 5-Sample anti-interference layer; 6-Sample detection layer; 7-Reflective mirror; 8-Liquid inlet; 9-Liquid outlet; 10-Light source generator; 11-Input fiber optic cable; 12-Fiber optic coupler; 13-Output fiber optic cable; 14-Signal analysis device; 15-Computer; 16-Detection sample; 17-Fiber optic curing adhesive. Detailed Implementation

[0027] The technical solutions of the present utility model will be clearly and completely described below with reference to the accompanying drawings of the embodiments. Obviously, the described embodiments are only some embodiments of the present utility model, and not all embodiments. Based on the embodiments of the present utility model, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the protection scope of the present utility model.

[0028] The purpose of this invention is to provide an anti-interference LSPR fiber optic sensing probe and sample detection device to solve the problems existing in the prior art and achieve high detection accuracy.

[0029] To make the above-mentioned objectives, features and advantages of this utility model more apparent and understandable, the utility model will be further described in detail below with reference to the accompanying drawings and specific embodiments.

[0030] Example 1

[0031] like Figures 1-3 As shown, this utility model provides an anti-interference LSPR fiber optic sensing probe, including a sensor connector 1. One end of the sensor connector 1 is used to connect to a detection fiber 2, and the other end of the sensor connector 1 is provided with a sensor outer tube 3 and a sensor capillary tube 4. It should be noted that although the other end of the sensor connector 1 is provided with a sensor capillary tube 4, the sensor connector 1 is actually connected to the sensor outer tube 3, and the sensor outer tube 3 and the sensor capillary tube 4 are relatively fixed. The sensor connector 1 is a plastic shell or other structure that can simultaneously connect the detection fiber 2 and the sensor outer tube 3. Both ends of the sensor connector 1 are provided with through-hole structures that are respectively connected to the detection fiber 2 and the sensor outer tube 3, so that the detection fiber 2 and the sensor outer tube 3 can be connected to the corresponding through-hole structures, and the through-hole structures on both sides can ensure that the axes of the detection fiber 2 and the sensor outer tube 3 are collinear. The sensor outer tube 3 is located outside the sensor capillary tube 4, and the sensor capillary tube 4 is located at the center of the sensor outer tube 3. The sensor capillary tube 4 and the sensor outer tube 3 are fixedly connected by fiber optic curing adhesive 17. A sample anti-interference layer 5 is provided on the outer wall of the sensor capillary 4, and a sample detection layer 6 is provided on the inner wall of the sensor capillary 4. A reflective mirror 7 is installed at the end of the sensor capillary 4 away from the sensor connector 1. Since the sensor capillary 4 has a tubular structure, the reflective mirror 7 has a ring structure. The reflective mirror 7 can reflect the light signal carrying the detection information, thereby reflecting the light signal transmitted from the detection optical fiber 2 back. The end of the sensor outer tube 3 away from the sensor connector 1 is a liquid inlet 8, and a liquid outlet 9 is provided on the side wall of the sensor connector 1. The liquid outlet 9 is located on the side of the sensor outer tube 3 close to the sensor connector 1.

[0032] When the anti-interference LSPR fiber optic sensing probe is connected to the sample detection device, the optical signal from the detection fiber 2 can be transmitted to the sensor capillary 4 and move along the sensor capillary 4 towards the reflecting mirror 7. When the optical signal reaches the reflecting mirror 7, it is reflected and returns to the detection fiber 2 along the same path. During the movement of the optical signal along the sensor capillary 4, a portion of the light passes through the sensor capillary 4 and undergoes total internal reflection at the wall of the sensor capillary 4, contacting the sample detection layer 6 and the sample anti-interference layer 5 respectively and exciting the NIR-LSPR effect and the VIS-LSPR effect. At the same time, due to the function of the liquid outlet 9, the sample 16 will enter from the liquid inlet 8 of the sensor outer tube 3 under the capillary action of the sensor capillary 4. The sample 16 enters both the inner and outer sides of the sensor capillary 4, and there is a space between the outer wall of the sensor capillary 4 and the sensor outer tube 3 that allows the sample to flow through. During the flow of sample 16, the NIR-LSPR effect is used to detect sample information, and the VIS-LSPR effect is used to compensate for the interference information caused by the volume refractive index in the sample information. These two data are then transmitted to the sample detection device, and more accurate detection results can be obtained through compensation and correction.

[0033] In this embodiment, the sample anti-interference layer 5 includes gold nanospheres. These gold nanospheres are fixed to the outer wall of the sensor capillary 4 through layer-by-layer self-assembly. Layer-by-layer self-assembly is a surface modification technique that uses alternating deposition of materials with opposite charges or complementary forces to construct multilayer films. This is a mature existing technology, and therefore the specific processing steps will not be further described here. The gold nanospheres are used to excite the VIS-LSPR effect for self-compensation calibration. The VIS-LSPR effect (visible light localized surface plasmon resonance) is a physical phenomenon in which the free electrons on the surface of metal nanoparticles oscillate collectively under visible light excitation.

[0034] Similarly, the sample detection layer 6 includes gold bipyramidal nanoparticles, which are fixed to the inner wall of the sensor capillary 4 through layer-by-layer self-assembly. These nanoparticles are used to excite the near-infrared LSPR (NIR-LSPR) effect. The NIR-LSPR effect (near-infrared localized surface plasmon resonance) is a phenomenon where conduction electrons of metal or semiconductor nanostructures oscillate collectively under near-infrared light (700-2500 nm) excitation. Furthermore, the assembled gold bipyramidal nanoparticles are chemically modified by sequentially immersing them in PDDA solution, PSS solution, and PAH solution, each solution for 15 minutes. Afterward, the gold bipyramidal nanoparticles are fixed to the sensor capillary 4, thereby modifying their surface with detection molecules associated with the sample to be tested, thus achieving sample-specific detection.

[0035] In this embodiment, the sensor capillary 4 is a quartz capillary. Because quartz capillary has high spectral transmittance, it is also called a light-guiding capillary. Using a quartz capillary can effectively meet the working requirements of light transmission.

[0036] In this embodiment, the reflective mirror 7 is a silver film with a thickness of 100 nm. Specifically, a silver film with a thickness of 100 nm or more can be deposited on one end face of the sensor capillary 4 using magnetron sputtering technology to reflect light.

[0037] In this embodiment, the end faces of the detection fiber 2 and the sensor capillary 4 are both planar structures. Specifically, existing fiber polishing sandpaper can be used to polish the end faces of the detection fiber 2 and the sensor capillary 4 to make them flat, thereby improving the light transmission efficiency.

[0038] In this embodiment, the cross-sectional diameter of the detection optical fiber 2 is larger than the cross-sectional diameter of the sensor capillary 4. The purpose of this arrangement is to ensure that the light emitted from the detection optical fiber 2 can be transmitted to the sensor capillary 4.

[0039] Example 2

[0040] like Figure 4 As shown, this embodiment provides a detection device, including the anti-interference LSPR fiber optic sensing probe disclosed in Embodiment 1.

[0041] In this embodiment, the device further includes a light source generating device 10, an input optical fiber 11, an optical fiber coupler 12, an output optical fiber 13, and a signal analysis device 14. The optical fiber coupler 12 is a conventional 1x2 optical fiber coupler. The light source generating device 10 is connected to the first interface of the optical fiber coupler 12 via the input optical fiber 11. The second interface of the optical fiber coupler 12 is connected to an anti-interference LSPR optical fiber sensing probe. Specifically, the second interface of the optical fiber coupler 12 is connected to the sensor connector 1 in the anti-interference LSPR optical fiber sensing probe via the detection optical fiber 2. The third interface of the optical fiber coupler 12 is connected to the signal analysis device 14 via the output optical fiber 13.

[0042] In practical use, the light source generator 10 emits an optical signal, which is transmitted to the anti-interference LSPR fiber optic sensing probe through the input fiber optic cable 11 and the fiber optic coupler 12. This signal is then used to detect the sample 16 in the anti-interference LSPR fiber optic sensing probe. The anti-interference LSPR fiber optic sensing probe then transmits the corresponding detection signal to the signal analysis device 14 through the fiber optic coupler 12 and the output fiber optic cable 13. This signal is then used to analyze and calibrate the detection data from the anti-interference LSPR fiber optic sensing probe.

[0043] In this embodiment, the light source generating device 10 is a broadband light source. A broadband light source is an optical device with a wide spectral range (covering hundreds of nanometer wavelengths) and low temporal coherence, which can provide stable and uniform illumination or signal excitation for high-precision optical systems.

[0044] In this embodiment, the signal analysis device 14 is a fiber optic spectrometer, which is capable of performing spectral analysis on the light being measured transmitted through the output fiber optic cable 13.

[0045] In this embodiment, the signal analysis device 14 is electrically connected to the computer 15 via a USB data cable, thereby transmitting the analysis results of the fiber optic spectrometer to the computer 15, so that the user can understand the detection information in a timely manner.

[0046] In the description of this utility model, it should be understood that the terms "longitudinal," "lateral," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," and "outer," etc., indicating orientation or positional relationships, are based on the orientation or positional relationships shown in the accompanying drawings and are only for the convenience of describing this utility model. They do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation on this utility model. Furthermore, the terms "first," "second," and "third," etc., are used for descriptive purposes only and should not be construed as indicating or implying relative importance. Thus, features defined with "first," "second," etc., may explicitly or implicitly include one or more of that feature. In the description of this utility model, unless otherwise stated, "a plurality of" means two or more.

[0047] In the description of this utility model, unless otherwise explicitly specified and limited, the terms "installation," "connection," and "joining" should be interpreted broadly. For example, they can refer to fixed connections, detachable connections, or integral connections; they can refer to mechanical connections or electrical connections; they can refer to direct connections or indirect connections through an intermediate medium; and they can refer to the internal communication between two components. Those skilled in the art can understand the specific meaning of the above terms in this application based on the specific circumstances.

[0048] If this utility model discloses or relates to mutually fixedly connected parts or structural components, then, unless otherwise stated, a fixed connection can be understood as: a detachable fixed connection (e.g., using bolts or screws), or a non-detachable fixed connection (e.g., riveting, welding). Of course, mutually fixed connections can also be replaced by an integral structure (e.g., manufactured using a casting process) (except where it is obviously impossible to use an integral forming process).

[0049] In addition, unless otherwise stated, the terms used in any of the technical solutions disclosed in this utility model to indicate positional relationships or shapes include states or shapes that are similar to, close to, or approximate with those states or shapes.

[0050] Any component provided by this utility model can be assembled from multiple individual components, or it can be a single component manufactured by a one-piece molding process.

[0051] It should be noted that the structures, proportions, sizes, etc., depicted in the accompanying drawings of this specification are only for the purpose of assisting those skilled in the art in understanding and reading the content disclosed in the specification, and are not intended to limit the conditions under which this utility model can be implemented. Therefore, they have no substantial technical significance. Any modifications to the structure, changes in the proportions, or adjustments to the size, without affecting the effects and objectives that this utility model can produce, should still fall within the scope of the technical content disclosed in this utility model.

[0052] It should also be noted that in the embodiments of this application, the same reference numerals are used to denote the same component or the same part.

[0053] Any adaptive changes made according to actual needs are within the protection scope of this utility model.

[0054] This utility model uses specific examples to illustrate its principles and implementation methods. The above description of the embodiments is only for the purpose of helping to understand the method and core idea of ​​this utility model. At the same time, for those skilled in the art, there will be changes in the specific implementation methods and application scope based on the idea of ​​this utility model. In summary, the content of this specification should not be construed as a limitation of this utility model.

Claims

1. An anti-interference LSPR fiber optic sensing probe, characterized in that: The sensor includes a sensor connector (1), one end of which is used to connect to a detection optical fiber (2). The other end of the sensor connector (1) is provided with a sensor outer tube (3) and a sensor capillary (4). The sensor outer tube (3) is located on the outside of the sensor capillary (4). The outer wall of the sensor capillary (4) is provided with a sample anti-interference layer (5). The inner wall of the sensor capillary (4) is provided with a sample detection layer (6). A reflective mirror (7) is installed at the end of the sensor capillary (4) away from the sensor connector (1). The reflective mirror (7) can reflect light signals carrying detection information. The end of the sensor outer tube (3) away from the sensor connector (1) is a liquid inlet (8). A liquid outlet (9) is provided on the side wall of the sensor connector (1).

2. The anti-interference LSPR fiber optic sensing probe according to claim 1, characterized in that: The sample anti-interference layer (5) includes gold nanospheres; the sample detection layer (6) includes gold nanobiconical particles.

3. The anti-interference LSPR fiber optic sensing probe according to claim 1, characterized in that: The sensor capillary (4) is a quartz capillary.

4. The anti-interference LSPR fiber optic sensing probe according to claim 1, characterized in that: The reflective mirror (7) is a silver film with a thickness of 100 nm.

5. The anti-interference LSPR fiber optic sensing probe according to claim 1, characterized in that: The end faces of both the detection optical fiber (2) and the sensor capillary (4) are planar structures.

6. The anti-interference LSPR fiber optic sensing probe according to claim 1, characterized in that: The cross-sectional diameter of the detection optical fiber (2) is larger than the cross-sectional diameter of the sensor capillary (4).

7. A sample detection device, characterized in that: Includes the interference-resistant LSPR fiber optic sensing probe as described in any one of claims 1-6; It also includes a light source generating device (10), an input optical fiber (11), an optical fiber coupler (12), an output optical fiber (13), and a signal analysis device (14). The light source generating device (10) is connected to the first interface of the optical fiber coupler (12) through the input optical fiber (11), the second interface of the optical fiber coupler (12) is connected to the anti-interference LSPR optical fiber sensing probe, and the third interface of the optical fiber coupler (12) is connected to the signal analysis device (14) through the output optical fiber (13).

8. The sample detection device according to claim 7, characterized in that: The light source generating device (10) is a broadband light source.

9. The sample detection device according to claim 7, characterized in that: The signal analysis device (14) is a fiber optic spectrometer.

10. The sample detection device according to claim 7, characterized in that: The signal analysis device (14) is electrically connected to the computer (15).

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