Optical fiber signal sensing immunodetection device and detector thereof

Abstract

The utility model belongs to the technical field of immunodetection equipment, and discloses an optical fiber signal sensing immunodetection device which comprises an optical fiber signal sensing immunodetection instrument and a sensing optical fiber, the optical fiber signal sensing immunodetector comprises a box body and a laser; the laser is arranged on the box body; the box body is provided with an embedding groove for inserting a mobile terminal; a first end of the sensing optical fiber is detachably connected with the laser, a second end of the sensing optical fiber detachably extends into the embedding groove and is used for transmitting an optical fiber signal to an optical sensor of the mobile terminal, and a bare fiber section is arranged on the sensing optical fiber and is coupled with an antigen or an antibody corresponding to the target protein to be detected. The optical fiber signal sensing immunodetection device can be applied to quantitative and qualitative detection of target protein, and has the characteristics of convenience in detection, accurate result and convenience in carrying.

Description

Technical Field

[0001] This utility model belongs to the technical field of immune detection equipment, specifically relating to an optical fiber signal sensing immune detection device and its detector. Background Technology

[0002] Currently, the detection of acute myocardial infarction (AMI) mainly relies on electrocardiography (ECG), coronary angiography, and specific biomarker testing. Although ECG is used for AMI diagnosis, its early concealment and nonspecificity make it difficult to diagnose in over 50% of ST-segment elevation myocardial infarction (STEMI) patients. While coronary angiography can visually observe coronary artery morphology and blood flow, its invasiveness and complexity limit rapid diagnosis, and it is also expensive and requires professional operation. Specific biomarker tests such as ELISA and CLIA have shown high sensitivity and accuracy in the quantitative measurement of myocardial injury markers, but the equipment is expensive, requires strict operating conditions, and has a long testing time. These limitations make widespread application difficult in resource-constrained primary healthcare units, especially in rural areas. Therefore, portable, simple, and sensitive point-of-care testing (POCT) devices are key to solving this problem.

[0003] To address this issue, portable and integrated point-of-care testing (POCT) devices are gaining increasing attention. Among them, light-initiated chemiluminescence assay (LICA) is a novel chemiluminescence analysis method that has been gradually accepted and applied in clinical laboratories. This technology differs from electrochemiluminescence, direct chemiluminescence, and enzyme-catalyzed chemiluminescence by employing two types of labeling: luminescent material and photoactive substance. The luminescent material is distributed on the surface of luminescent microspheres, and the photoactive substance is distributed on the surface of photosensitive microspheres, exhibiting "dual labeling" and "dual-sphere" characteristics. The two types of microspheres bind via antigen-antibody binding, enabling the transfer of high-energy reactive oxygen species and inducing a photoexcitation chemiluminescence process. This achieves homogeneous immunoassay without separation, offering excellent performance characteristics such as ease of operation, high analytical efficiency, and low instrument failure rate, making it popular in clinical laboratories. Despite its ease of operation and speed, it has some significant drawbacks in the detection of cardiac troponin. First, LICA results are susceptible to interference. Because it relies on an immune reaction on a nitrocellulose membrane, it is easily affected by other components in the sample or environmental factors, leading to reduced accuracy. Second, LICA exhibits poor stability in quantitative detection. Although results are obtained quickly, its repeatability and consistency are low, a significant drawback for clinical applications requiring precise measurement of cardiac troponin concentration. Furthermore, LICA typically only performs qualitative or semi-quantitative detection, making it difficult to provide accurate numerical results, and its devices are bulky, inconvenient for portability and field use.

[0004] The widespread adoption and powerful functionality of smartphones have brought new ideas to point-of-care testing (POCT) technology, leading to the development of various POCT platforms by combining smartphones with traditional detection techniques. However, smartphones still face challenges in detecting myocardial injury biomarkers, such as camera variations and environmental interference. Smartphone transmittance sensors (TLS) offer advantages such as a wide spectral response range, strong anti-interference capabilities, and low cost. By calculating the absorbance of metal antibodies based on absorbance analysis principles, direct detection of cardiac troponin can be achieved. Although smartphone TLS has shown potential in biochemical detection, there is currently no dedicated portable point-of-care testing device specifically designed for smartphones that can rapidly perform qualitative and quantitative detection. Utility Model Content

[0005] The purpose of this invention is to provide a portable fiber optic signal sensing immunoassay device that can detect protein samples instantly, quickly, qualitatively, and quantitatively.

[0006] The following technical solutions are used to achieve the above objectives.

[0007] The first aspect of this utility model provides an optical fiber signal sensing immunodetection device, which includes an optical fiber signal sensing immunodetector and a sensing optical fiber.

[0008] The fiber optic signal sensing immunoassay analyzer includes a housing and a laser; the laser is disposed on the housing; the housing is provided with an embedding slot for inserting a mobile terminal;

[0009] The first end of the sensing optical fiber is detachably connected to the laser, and the second end of the sensing optical fiber is detachably inserted into the embedding slot and used to transmit the optical fiber signal to the photosensor of the mobile terminal. The sensing optical fiber is provided with bare fiber segments, and the bare fiber segments are coupled with antigens or antibodies corresponding to the target protein to be detected.

[0010] In some embodiments, the fiber optic signal sensing immunoassay device further includes gold oxide platinum iron nanoparticles, which are coupled with antigens or antibodies corresponding to the target protein to be detected.

[0011] In some embodiments, the bare fiber segment of the sensing fiber is embedded in a capillary tube;

[0012] The box body is provided with a support member on the side opposite to the embedding groove. The support member has a receiving groove. The receiving groove has an opening structure at both ends along the extension direction of the box body. The capillary tube is detachably installed in the receiving groove.

[0013] In some embodiments, the support member includes a bottom plate, a side plate, and a top plate. A first end of the bottom plate is connected to the box body, a second end of the bottom plate is connected to the bottom end of the side plate, a top end of the side plate is connected to the top plate, and a gap is formed between the top end of the top plate away from the side plate and the box body. The bottom plate, side plate, and top plate cooperate to form the receiving groove with openings at both ends and at the top.

[0014] In some embodiments, the carrier has a notch in the middle so that the carrier forms a segmented arrangement on the box.

[0015] In some embodiments, the sensing optical fiber is wound around the outer peripheral wall of the housing.

[0016] In some embodiments, the outer peripheral wall of the housing is provided with a groove, and the sensing optical fiber is detachably accommodated in the groove.

[0017] In some embodiments, the output end of the laser is provided with a first fiber optic connector, and the first end of the sensing fiber is detachably connected to the first fiber optic connector.

[0018] In some embodiments, the housing is provided with a second optical fiber connector communicating with the embedded slot, and the second end of the sensing optical fiber is detachably connected to the second optical fiber connector.

[0019] In some embodiments, the housing has a first fixing plate and a second fixing plate extending outward from the position corresponding to the embedding slot. The first fixing plate and the second fixing plate are arranged opposite to each other, and a slot is formed on the opposite side of the first fixing plate and the second fixing plate. The mobile terminal is inserted into the embedding slot along the slot.

[0020] The second aspect of this utility model provides a fiber optic signal sensing immunoassay analyzer, which includes a housing and a laser; the laser is disposed on the housing; the housing is provided with an embedding slot for inserting a mobile terminal, and one side of the housing is provided with a carrier for supporting a reaction container; the output end of the laser is provided with a first fiber optic connector for detachable connection with a sensing fiber optic cable; the housing is provided with a second fiber optic connector communicating with the embedding slot for detachable connection with the sensing fiber optic cable.

[0021] In this invention, the fiber optic signal sensing immunoassay device has an embedded slot in the housing for inserting a mobile terminal. The first end of the sensing fiber is detachably connected to a laser, and the second end is detachably inserted into the embedded slot to transmit the fiber optic signal to the photosensor of the mobile terminal. The sensing fiber has bare fiber segments coupled with antigens or antibodies corresponding to the target protein to be detected. Therefore, this fiber optic signal sensing immunoassay device can be applied to the quantitative and qualitative detection of target proteins. The antigens or antibodies coupled to the bare fiber segments of the sensing fiber can bind with the target protein in the test sample to form an antibody sandwich structure, thereby affecting the light transmission of the sensing fiber. Therefore, by detecting the difference in light intensity signals received by the ambient light sensor of the smartphone, the protein sample can be quickly qualitatively and quantitatively detected. Thus, it can achieve the advantages of convenient detection, accurate results, and portability. After completing one test, other protein samples can be qualitatively and quantitatively detected by replacing the sensing fiber. Attached Figure Description

[0022] Figure 1 This is a schematic diagram of the overall structure of the fiber optic signal sensing immunoassay analyzer according to an embodiment of this utility model.

[0023] Figure 2 yes Figure 1 A partial structural diagram of the fiber optic signal sensing immunoassay analyzer from another angle.

[0024] Figure 3 yes Figure 2 A schematic diagram of the exploded structure of a fiber optic signal sensing immunoassay analyzer.

[0025] Figure 4 This is a graph showing the results of light intensity difference detection for standard solutions of different concentrations.

[0026] Figure 5 This is a graph showing the optical power detection results of standard solutions of different concentrations.

[0027] Figure 6 This is a graph showing the correlation between the light intensity difference detection results and the light power detection results.

[0028] Figure 7 It uses a fiber optic signal sensing immunoassay device to detect the SD and CV values ​​of standards at different concentrations.

[0029] Figure 8 This is a graph showing the test results of a clinical sample detected using a fiber optic signal sensing immunoassay device.

[0030] Explanation of reference numerals in the attached figures:

[0031] 1. Box body; 11. Embedded groove; 12. Supporting component; 121. Receiving groove; 122. Bottom plate; 123. Side plate; 124. Top plate; 125. Notch; 13. Groove; 14. First fixing plate; 15. Second fixing plate; 2. Reaction vessel; 3. Laser; 4. Sensing fiber; 5. First fiber optic connector; 6. Second fiber optic connector; 7. Power supply. Detailed Implementation

[0032] To facilitate understanding of this utility model, a more comprehensive description will be provided below. This utility model can be implemented in many different forms and is not limited to the embodiments described herein. Rather, these embodiments are provided to provide a more thorough and complete understanding of the disclosure of this utility model.

[0033] Unless otherwise specified, experimental methods in the following examples are generally performed under standard conditions or as recommended by the manufacturer. All commonly used chemical reagents used in the examples are commercially available products.

[0034] Unless otherwise defined, all technical and scientific terms used in this invention have the same meaning as commonly understood by one of ordinary skill in the art to which this invention pertains. The terminology used in this specification is for the purpose of describing particular embodiments only and is not intended to limit the invention. The term "and / or" as used in this invention includes any and all combinations of one or more of the associated listed items.

[0035] This utility model provides an optical fiber signal sensing immune detection device, such as... Figures 1 to 3As shown, the fiber optic signal sensing immunodetection device includes a fiber optic signal sensing immunodetector and a sensing fiber 4; the fiber optic signal sensing immunodetector includes a housing 1 and a laser 3; the laser 3 is disposed on the housing 1; the housing 1 is provided with an embedding slot 11 for inserting a mobile terminal.

[0036] The first end of the sensing fiber 4 is detachably connected to the laser 3, and the second end of the sensing fiber 4 is detachably inserted into the embedding slot 11 and used to transmit the fiber optic signal to the photosensor of the mobile terminal. The sensing fiber 4 is provided with a bare fiber segment, and the bare fiber segment is coupled with an antigen or antibody corresponding to the target protein to be detected.

[0037] The fiber optic signal sensing immunoassay device features an embedded slot 11 in the housing 1 for inserting a mobile terminal. The first end of the sensing fiber 4 is detachably connected to a laser 3, and the second end is detachably inserted into the embedded slot 11 to transmit the fiber optic signal to the mobile terminal's photosensor. The sensing fiber 4 has bare fiber segments coupled with antigens or antibodies corresponding to the target protein. Therefore, this fiber optic signal sensing immunoassay device can be used for quantitative and qualitative detection of target proteins. The antigens or antibodies coupled to the bare fiber segments of the sensing fiber 4 can bind to the target protein in the test sample, forming an antibody sandwich structure that affects the light transmission of the sensing fiber 4. Thus, the protein sample can be qualitatively and quantitatively detected based on the light intensity signal received by the smartphone's ambient light sensor. After completing one test, other protein samples can be repeatedly tested by replacing the sensing fiber 4. When applied to target protein detection, it features high detection sensitivity, convenient detection, accurate results, and portability.

[0038] In some embodiments, the fiber optic signal sensing immunoassay device further includes gold-platinum-iron oxide nanoparticles, which are coupled with an antigen or antibody corresponding to the target protein to be detected. Specifically, a test sample, such as serum, is injected into the reaction container 2. This test sample has been pre-incubated with gold-platinum-iron oxide nanoparticles coupled with the antigen or antibody corresponding to the target protein (antibody two). A bare fiber segment of the sensing fiber 4, coupled with the antigen or antibody corresponding to the target protein to be detected (antibody one), is placed in the reaction container 2, forming a double-antibody sandwich structure of antibody one, target protein to be detected, and antibody two coupled with gold-platinum-iron oxide nanoparticles. At this time, a portion of the 625nm emitted light through the sensing area of ​​the sensing fiber 4 is absorbed by the gold-platinum-iron oxide nanoparticles. Therefore, by inserting a mobile terminal, such as a smartphone, into the embedding slot 11, the sample can be qualitatively and quantitatively detected by performing differential analysis using the smartphone's ambient light sensor application.

[0039] In some embodiments, the reaction container 2 is a capillary tube, and the bare fiber segment of the sensing optical fiber 4 is embedded within the capillary tube. Specifically, by setting the reaction container 2 as a capillary tube, the test sample can be drawn up using other capillaries or micro-syringes, and the test sample can be conveniently injected into the capillary tube by connecting the interfaces of the two, effectively preventing the test sample from flowing out of the reaction container 2 under natural conditions. The bare fiber segment of the sensing optical fiber 4 is obtained by stripping a 2-2.5 cm bare fiber segment from the middle of the optical fiber using optical fiber stripping pliers. Then, the optical fiber is fixed on a manual tapering platform, and the bare fiber segment is burned using a flame torch to taperize the optical fiber to obtain the bare fiber segment. That is, the core diameter of the bare fiber segment is smaller than the core diameter of other areas, so as to be embedded in the inner cavity of the capillary tube for reaction.

[0040] In some embodiments, such as Figure 2 As shown, a support member 12 is provided on the side of the box body 1 opposite to the embedding groove 11. The support member 12 has a receiving groove 121, and the receiving groove 121 has openings at opposite ends along the extension direction of the box body 1. Specifically, the support member 12 is arranged along the length of the back of the box body 1, and the support member 12 has these openings at opposite ends along the length direction of the box body 1. The openings at opposite ends of the support member 12 facilitate the insertion of a reaction container 2, such as a capillary tube, through these openings, and also facilitate the removal of the capillary tube when it is replaced, allowing the capillary tube to be detachably placed in the receiving groove 121. Furthermore, it also facilitates the connection of other capillary tubes or micro-syringes to the capillary tube interface after drawing up the test sample, thereby injecting the test sample into the reaction container 2.

[0041] Specifically, in the embodiments, such as Figure 2 As shown, the support member 12 includes a bottom plate 122, a side plate 123, and a top plate 124. The first end of the bottom plate 122 is connected to the box body 1, the second end of the bottom plate 122 is connected to the bottom end of the side plate 123, the top end of the side plate 123 is connected to the top plate 124, and a gap is formed between the end of the top plate 124 away from the side plate 123 and the box body 1. The bottom plate 122, the side plate 123, and the top plate 124 cooperate to form the receiving groove 121 with openings at both ends and the top.

[0042] In some embodiments, the carrier 12 has a notch 125 in the middle, so that the carrier 12 forms a segmented arrangement structure on the housing 1. By forming the notch 125 in the middle of the carrier 12, the middle part of the capillary is exposed outside the carrier 12. An operator can quickly replace the capillary by applying external force to the exposed capillary on the carrier 12, causing it to extend from the end opening.

[0043] In some embodiments, such as Figure 1As shown, the sensing fiber 4 is wound around the outer peripheral wall of the housing 1. Specifically, the laser 3 is disposed inside the housing 1, wherein the embedding slot 11 is disposed at the front end of the housing 1 facing the operator, the carrier 12 is disposed at the back end of the housing 1, the laser 3 is disposed laterally inside the housing 1, and the output end of the laser 3 is disposed on the left side of the housing 1. Therefore, the sensing fiber 4 has a relatively long length because it needs to extend from the position of the laser 3 to the reaction container 2 at the carrier 12 and then terminate at the mobile terminal at the embedding slot 11. By winding the sensing fiber 4 around the outer peripheral wall of the housing 1, the laser 3, the reaction container 2 and the mobile terminal can be well connected together, which facilitates assembly and makes the wiring more organized, avoiding messy lines.

[0044] Specifically, in the embodiments, such as Figure 1 As shown, the outer peripheral wall of the housing 1 is provided with a groove 13, and the sensing optical fiber 4 is detachably accommodated in the groove 13. The sensing optical fiber 4 is secured in the groove 13, which can better fix the sensing optical fiber 4 on the housing 1, further improving the stability of the sensing optical fiber 4, and also has the characteristics of easy assembly and disassembly.

[0045] In some embodiments, such as Figure 1 As shown, the output end of the laser 3 is provided with a first fiber optic connector 5, and the housing 1 is provided with a second fiber optic connector 6 communicating with the embedding slot 11. The first end of the sensing fiber 4 is detachably connected to the first fiber optic connector 5, and the second end is detachably connected to the second fiber optic connector 6. The first fiber optic connector 5 and the second fiber optic connector 6 are conventional fiber optic connectors, which can securely and detachably connect the sensing fiber 4 to the laser 3 and the housing 1 at preset positions. By fixing the first fiber optic connector 5 at the output end of the laser 3 and providing the second fiber optic connector 6 at the embedding slot 11, the sensing fiber 4 can be quickly, accurately, and detachably assembled.

[0046] In some embodiments, such as Figure 1 As shown, the housing 1 has a first fixing plate 14 and a second fixing plate 15 extending outward from the position corresponding to the embedding slot 11. The first fixing plate 14 and the second fixing plate 15 are arranged opposite to each other, and each of the first fixing plate 14 and the second fixing plate 15 has a slot on its opposite side. The mobile terminal is inserted into the embedding slot 11 along the slot. The first fixing plate 14 and the second fixing plate 15 limit the opposite sides of the mobile terminal, such as a smartphone, and the embedding slot 11 limits the head end of the smartphone, so that the smartphone can be accurately inserted into the embedding slot 11, and the smartphone's light sensor can be accurately aligned with the second end of the sensing optical fiber 4, so that the light signal of the sensing optical fiber 4 can be accurately transmitted to the smartphone's light sensor for result detection.

[0047] In some embodiments, the laser 3 is capable of emitting 625nm laser light.

[0048] In some embodiments, such as Figure 3 As shown, the box 1 is also equipped with a power supply 7, which is used to supply power to the laser 3 and has a charging and energy storage function.

[0049] In some embodiments, the housing 1 is further provided with a power control device for controlling the power of the laser 3. The control knob of the power controller is aligned with and engaged with the knob opening of the housing 1 for power control of the laser 3.

[0050] In some embodiments, the housing 1 is also provided with conventional components such as a microcontroller and a switch. The microcontroller is located at the bottom of the housing 1, and the switch is located on the surface of the housing 1. The microcontroller is connected to the laser 3, the power controller, and the switch to control the working state of each component.

[0051] This utility model embodiment also provides a fiber optic signal sensing immunoassay analyzer, which includes a housing 1 and a laser 3; the laser 3 is disposed on the housing 1; the housing 1 is provided with an embedding slot 11 for inserting a mobile terminal, and one side of the housing 1 is provided with a support member 12 for supporting a reaction container 2; the output end of the laser 3 is provided with a first fiber optic connector 5 for detachable connection with a sensing fiber 4; the housing 1 is provided with a second fiber optic connector 6 that communicates with the embedding slot 11 and is detachably connected with the sensing fiber 4.

[0052] The present invention will now be described in conjunction with specific embodiments.

[0053] Example 1: Construction of a method for detecting cardiac troponin I

[0054] The fiber optic signal sensing immunoassay device is based on the principle of immunoadsorption technology and includes the following:

[0055] The sensing fiber and fiber optic signal sensing immunoassay analyzer are assembled, and a smartphone is inserted into the mounting slot of the housing. Serum samples are then coupled with a signal probe (gold oxide platinum iron nanoparticles coupled with cTnI antibody, Fe...). x O y @Au α Pt β-dAb) mixed incubation, after which approximately 1 / 2 dAb sample was drawn up using a capillary tube or microsyringe and injected into a glass reaction dish. The sensing region of the sensing fiber coupled with cTnI antibody-1 (16A11cc antibody) was mixed with the sample in the glass reaction dish for incubation. Then the switch was turned on, the power controller current was adjusted to 2A, and the light intensity signal received by the ambient light sensor of the smartphone was immediately recorded as the initial value, denoted as Δ1. If cardiac troponin I is present in the serum, it will react with Fe x O y @Au α Pt β The -dAb signal probe binds to the 16A11cc capture probe on the optical fiber, forming a double-antibody sandwich structure of "gold oxide platinum iron nanoparticle-labeled cTnI antibody II - cardiac troponin I - cTnI antibody I". At this point, a portion of the 625nm emitted light from the sensing region of the sensing fiber is absorbed by the gold oxide platinum iron nanoparticles. After incubation for a period, the serum is removed using a capillary glass tube or a micro-syringe, and the light intensity signal received by the smartphone's ambient light sensor is recorded as the final value, denoted as Δ2. Differential analysis is performed using the smartphone's ambient light sensor application, and the difference between the final and initial values ​​(Δ2-Δ1) is selected as the analytical value. Δ2-Δ1 represents the light intensity absorbed by the gold oxide platinum iron nanoparticles. The concentration of cardiac troponin I in the analyte is defined in real-time by calculating the light intensity absorbed by the gold oxide platinum iron nanoparticles.

[0056] 1.1 The experimental reagents are shown in the table below.

[0057] Table 1 Experimental Reagents

[0058]

[0059]

[0060] 1.2 Preparation of the main solution

[0061] (1) Prepare phosphate buffer (PBS, 1×) 0.015 mol / L pH=7.0, 0.1 mol / L pH=7.0 MES buffer, 10 mg / mL EDC solution (ready to use), 10 mg / mL NHS solution (ready to use), and 10% (w / v) BSA solution according to conventional methods.

[0062] (2) The preparation of the labeling complex solution is shown in Table 2.

[0063] Table 2. Reconstitution Solution Formulations

[0064]

[0065]

[0066] The solutions prepared above, including the EDC solution and NHS solution, should be used immediately and not stored for extended periods. Except for 1XPBS, all others should be stored at 4°C.

[0067] 1.3 Preparation of Gold Oxide Platinum Iron Nanoparticle Suspension

[0068] (1) Prepare a HAuCl4 solution with a concentration of 24 mmol / L and an H2PtCl6 solution with a concentration of 24 mmol / L, and mix them in a 1:1 ratio to obtain a 0.5 ml mixture;

[0069] (2) Add the mixture to 200ml of water and stir continuously. At 300rpm and 25℃, add 500μL of 0.5% ammonia water quickly to the mixture and stir continuously for 2min.

[0070] (3) Prepare 3 mL of 0.5 mol / L FeCl2 solution, add it quickly to the mixture, and stir continuously for 20 min;

[0071] (4) Centrifuge at 8000 rpm for 10 min;

[0072] (5) Wash the product three times with 50 mL of H2O;

[0073] (6) The resulting product was redissolved in 6 mL of H₂O and named Fe. x O y @Au α Pt β -NPs (2 mg / mL).

[0074] 1.4 Preparation of signal probes

[0075] After preparing the gold oxide platinum iron nanoparticle suspension as described above, before preparing the signal probe with cTnI antibody using microsphere immunolabeling antibody technology, the surface of the gold oxide platinum iron nanoparticles needs to be treated. Under the activation of EDC / NHS, the nanoparticles undergo an amide reaction with the amino groups on the antibody to form stable amide bonds. The specific steps are as follows:

[0076] (1) Fe x O y @Au α Pt β - The NPs suspension was ultrasonically resuspended and mixed (power 5%, on for 2 seconds, off for 3 seconds), repeated 12 times until the precipitate was uniformly dispersed into a solution. Then, 0.5 mL of Fe was aspirated. x O y @Au α Pt β -NPs suspension, diluted to 1 mL of Fe with a concentration of 1 mg / mLx O y @Au α Pt β -NPs suspension;

[0077] (2) Add 1 mL of Fe with a concentration of 1 mg / mL x O y @Au α Pt β - The NPs suspension was mixed with 100 μL of sodium polyacrylate (PAA) and incubated by rotation at room temperature for 2 h.

[0078] (3) Use 1 mL of pure water to incubate the Fe with PAA. x O y @Au α Pt β -NPs were centrifuged at 8000 rpm for 5 min, purified, and dispersed in 2 mL of MES buffer (10 mmol / L, pH = 7.0);

[0079] (4) Add 20 μL of EDC activation solution (concentration of 10 mg / mL) and 20 μL of NHS solution (concentration of 10 mg / mL) to the above solution, vortex mix, and activate at room temperature by rotating in a rotary mixer for 40 min.

[0080] (5) After incubation, add 9.76 μL (4.1 mg / mL) cTnI antibody II (19C7cc antibody), wrap with tin foil to protect from light at room temperature, and incubate by rotating in a rotary mixer for 3 hours.

[0081] (6) Add 20 μL of BSA (1%) blocking solution to the above solution, wrap it with tin foil to protect it from light at room temperature, and rotate it in a rotary mixer for 30 min.

[0082] (7) Using 1 mL of pure water at 8000 rpm, Fe x O y @Au α Pt β Centrifuge the -dAb for 5 min and repeat the purification process 3 times.

[0083] (8) Discard the supernatant, add 1 mL of labeled reconstitution solution (5% w / v BSA, 0.5% w / v T-20, 5% w / v sucrose, 20 mmol / L Tris-HCl) to the precipitate, and sonicate to mix thoroughly. This successfully prepares a signal probe (Fe) of gold oxide platinum iron nanoparticles coupled with cTnI antibody. x O y @Au α Pt β Store the dAb at 4°C in a cool, dark place for later use.

[0084] 1.5 Preparation of the capture probe

[0085] (1) Prepare a Corning multimode optical fiber of appropriate length, pre-treat the optical fiber, use optical fiber stripping pliers to strip a bare fiber segment of 2-2.5cm in the middle of the optical fiber, and strip the coating at both ends of the optical fiber. The two ends of the optical fiber with the stripped coating are used for subsequent assembly with the first connector (optical fiber probe) and the second connector (optical fiber probe) of the optical fiber signal sensing immunoassay detector. Then fix the optical fiber on the manual tapering platform, use a flame torch to burn the bare fiber segment, and tape the optical fiber to obtain a bare fiber segment with a tapering length of about 1cm. The total length of the bare fiber segment is about 3-3.5cm.

[0086] (2) Bend the prepared optical fiber at about 90° and fix it to the surface of the glass slide with medical tape. Extend the bare fiber section and fix the glass slide at a suitable height on the iron stand.

[0087] (3) Mix 98% concentrated sulfuric acid and 30% H2O2 in a ratio of 3:1 to prepare a piranha solution. Then place the piranha solution on an iron stand and immerse the bare fiber segment in the piranha solution for 30 minutes to perform hydroxylation treatment on the bare fiber segment (hereinafter referred to as the sensing area).

[0088] (4) Soak the sensing area in pure water for 5 minutes to remove residual solution;

[0089] (5) Prepare a 5% APTES solution by mixing anhydrous ethanol with 3-aminopropyltriethoxysilane (APTES), then place the 5% APTES solution on an iron stand and immerse the sensing area in the 5% APTES solution for 2 hours to generate amino groups.

[0090] (6) Soak the sensing area in pure water for 5 minutes to remove residual solution;

[0091] (7) Prepare a 5% glutaraldehyde solution by mixing PBS with glutaraldehyde. Then place the 5% APTES solution on an iron stand and immerse the sensing area in the 5% APTES solution for 30 min. The amino group of the fiber reacts with one aldehyde group of glutaraldehyde, while the other aldehyde group of glutaraldehyde can bind to the amino group of cTnI antibody in the next step.

[0092] (8) Clean the sensing area three times with pure water;

[0093] (9) Prepare an antibody solution by mixing PBS with cTnI antibody-16A11cc antibody. Use about 2 μg of antibody per optical fiber. Place the antibody solution on an iron stand and immerse the sensing area in the antibody solution for 4 hours to successfully fix cTnI-16A11cc antibody on the surface of the sensing area.

[0094] (10) Wash the unreacted antibody with pure water;

[0095] (11) Immerse the optical fiber in 1% BSA solution for 30 min to block the unreacted aldehyde groups on the fiber surface and obtain the capture probe (sensing optical fiber coupled with 16A11cc antibody).

[0096] 1.6 Structure of the Fiber Optic Signal Sensing Immunoassay Analyzer

[0097] like Figures 1 to 3 As shown, the fiber optic signal sensing immunoassay analyzer includes a housing 1, a carrier 12, a microcontroller, a 625nm laser 3, a power controller, a switch, a battery 7, a capillary tube, a first fiber optic connector 5, and a second fiber optic connector 6. The capillary tube, serving as the reaction container, is interlocked with the bare fiber segment of the sensing fiber 4. The sensing fiber 4 is used for the detection and sensing of cardiac troponin I. The microcontroller is used for power supply and laser conversion. The 625nm laser 3 is used for optical signal emission. The power controller controls the power of the battery 7, which provides power to the fiber optic signal sensing immunoassay analyzer. The switch controls the state of the fiber optic signal sensing immunoassay analyzer. A 625nm laser 3 is disposed inside the housing 1. A smartphone is inserted into the embedding slot 11 of the housing 1. A capillary tube is supported on a carrier 12. The first end of the sensing fiber 4 is connected to the laser 3 through a first fiber optic connector 5. The second end of the sensing fiber 4 extends into the embedding slot 11 through a second fiber optic connector 6 and is used to transmit the fiber optic signal to the photosensitive sensor of the mobile terminal. The bare fiber segment of the sensing fiber 4 embedded in the capillary tube is coupled with cTnI antibody-16A11cc antibody.

[0098] The detection steps of this fiber optic signal sensing immunoassay analyzer are as follows:

[0099] (1) Take 100 μL of the sample to be tested and add it into the capillary reaction vessel. Turn on the switch of the fiber optic signal sensing immunoassay analyzer and control the current to 2A. Record the initial value Δ1 measured by the ambient light sensor of the smartphone.

[0100] (2) Remove the sample after 5 min and record the final value Δ2 measured by the smartphone ambient light sensor;

[0101] (3) The difference between the final value and the initial value (Δ2-Δ1) is used as the analysis value.

[0102] 1.7 Preparation of serum

[0103] (1) Freshly collected venous blood (2-5 mL) is placed into a red-capped blood collection tube (without added anticoagulant), and left to stand at room temperature for 30-60 minutes or at 2-8℃ overnight until the blood coagulates;

[0104] (2) Centrifugation: room temperature, 3500 rpm, 5 min;

[0105] (3) Sampling: Extract the upper serum layer for testing;

[0106] (4) Storage: Store at 2-8℃ for 24 hours, or at -15℃ or below for 90 days.

[0107] Example 2: Detection of cardiac troponin I

[0108] (1) Standard product testing

[0109] The three sensing optical fibers prepared in Example 1 were used in conjunction with an optical fiber signal sensing immunoassay analyzer to detect standard solutions of different concentrations (0.1 ng / mL, 0.2 ng / mL, 0.4 ng / mL, 0.8 ng / mL, and 1.6 ng / mL, Shanghai Lingchao Biotechnology, recombinant cardiac troponin I (cTnI) antigen), and the tests were performed three times using a smartphone and an optical power meter.

[0110] The detection method is as follows:

[0111] Smartphone testing procedure: Connect the smartphone to the mounting slot of the fiber optic signal sensor immunoassay analyzer, and mix 100 μL of serum sample with 10 μL of effusion. x O y @Au α Pt β -dAb was mixed and incubated. After incubation, 50 μL of sample was injected into a glass reaction dish using a capillary tube or microsyringe. The switch was then turned on, and the power controller current was adjusted to 2A. The light intensity signal received by the smartphone's ambient light sensor was immediately recorded as the initial value, denoted as Δ1. After incubation for 6 minutes, the serum was removed using a capillary tube or microsyringe, and the light intensity signal received by the smartphone's ambient light sensor was recorded again as the final value, denoted as Δ2. Difference analysis was performed using the smartphone's ambient light sensor application, and the difference between the final value and the initial value (Δ2-Δ1) was selected as the analytical value. The results are as follows: Figure 4 As shown.

[0112] Optical power meter detection operation: The optical power meter is fitted into the slot of the fiber optic signal sensor immunoassay analyzer, and the serum sample is mixed with Fe... x O y @Au α Pt β-dAb was mixed and incubated. After incubation, approximately 100 μL of sample was aspirated using a capillary tube or microsyringe and injected into a glass reaction dish. The switch was then turned on, and the power controller current was adjusted to 2A. The light intensity signal received by the optical power meter was immediately recorded as the initial value, denoted as α1. After 6 minutes of incubation, the serum was removed using a capillary tube or microsyringe, and the light intensity signal received by the optical power meter was recorded again as the final value, denoted as α2. Difference analysis was performed based on the light power results, and the difference between the final value and the initial value (α2-α1) was selected as the analytical value. The results are as follows: Figure 5 As shown.

[0113] Analysis of test results:

[0114] like Figure 6 As shown, by comparing the numerical values ​​of the two signal detection devices, standard solutions of different concentrations were detected using an optical power meter and a smartphone, respectively. Detection curves and fitted standard curves were plotted with the optical power meter values ​​as the X-axis and the smartphone values ​​as the Y-axis. The detection results of the two signal receiving devices showed a high correlation, with the linear range of detection being 0.1-1.6 ng / mL.

[0115] (2) Stability analysis

[0116] The sensing fiber prepared in Example 1, combined with a fiber optic signal sensing immunoassay analyzer, was used to detect the concentrations of three standard solutions (Shanghai Lingchao Biotechnology, recombinant cardiac troponin I (cTnI) antigen) at high, medium, and low concentrations (1.6 ng / mL, 0.8 ng / mL, and 0.2 ng / mL), with each concentration repeated five times. The detection method is as follows:

[0117] Also as shown in Table 3 and Figure 7 As shown, the SD and CV values ​​of the fiber optic sensing standard are within acceptable ranges, and the CV value of this detection method can be controlled within 15%, which meets the requirements of clinical testing.

[0118] Table 3 Stability Analysis

[0119] Group Mean Standard deviation (SD) Coefficient of variation (CV) High value group (1.6 ng / mL) 1.564 ng / mL 0.157 10.02％ Median group (0.8 ng / mL) 0.709 ng / mL 0.050 7.00％ Low value group (0.2 ng / mL) 0.214 ng / mL 0.021 9.68％

[0120] (3) Recovery rate analysis

[0121] The sensing fiber prepared in Example 1 was used in conjunction with a fiber optic signal sensing immunoassay analyzer to detect the concentrations of three standard solutions (Shanghai Lingchao Biotechnology, recombinant cardiac troponin I (cTnI-16A11cc) antigen) at high, medium, and low concentrations, respectively (1.6 ng / mL, 0.8 ng / mL, and 0.2 ng / mL), with each concentration being repeated five times.

[0122] Meanwhile, as shown in Table 4 below, the recovery rate of the fiber optic sensing standard is controlled within 85-115%, which meets the requirements of clinical testing.

[0123] Table 4 Recovery Rate Analysis

[0124]

[0125]

[0126] (4) Clinical sample testing

[0127] Twenty-one clinical samples (from the Second People's Hospital of Guangdong Province) were collected and tested using the sensing fiber optic combined with a fiber optic signal sensing immunoassay analyzer prepared in Example 1. The ambient light sensor of a smartphone was used as the receiving device. The test results are as follows. Figure 8 As shown, the detection limit of this invention is 0.036 ng / mL, and the detection range is 0.08-1.5 ng / mL, which meets the clinical testing requirements.

[0128] In summary, a fiber optic signal sensing immunoassay analyzer was constructed using a 625nm laser signal transmitter and associated components. The power of this analyzer can be freely controlled. By combining the sensing fiber with the analyzer, a fiber optic signal sensing immunoassay device for cardiac troponin was obtained. This device can utilize a double-antibody sandwich method to initiate subsequent analysis processes and uses the ambient light sensor of a smartphone to determine changes in the light signal. This forms a light-signal-based sensing immunoassay device that enables one-step sample addition and one-step reaction, is less susceptible to environmental interference, is cost-effective, and easy to operate. It can be effectively applied in immunoassay and has a wide range of applications.

[0129] The technical features of the above embodiments can be combined in any way. For the sake of brevity, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0130] The embodiments described above are merely illustrative of several implementations of this utility model, and while the descriptions are relatively specific and detailed, they should not be construed as limiting the scope of the utility model patent. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of this utility model, and these all fall within the protection scope of this utility model. Therefore, the protection scope of this utility model patent should be determined by the appended claims.

Claims

1. A fiber optic signal sensing immunoassay device, characterized in that, The fiber optic signal sensing immunodetection device includes a fiber optic signal sensing immunodetector and a sensing fiber optic cable. The fiber optic signal sensing immunoassay analyzer includes a housing and a laser; the laser is disposed on the housing; the housing is provided with an embedding slot for inserting a mobile terminal; The first end of the sensing optical fiber is detachably connected to the laser, and the second end of the sensing optical fiber is detachably inserted into the embedding slot and used to transmit the optical fiber signal to the photosensor of the mobile terminal. The sensing optical fiber is provided with bare fiber segments, and the bare fiber segments are coupled with antigens or antibodies corresponding to the target protein to be detected.

2. The fiber optic signal sensing immunoassay device as described in claim 1, characterized in that, The fiber optic signal sensing immunoassay device also includes gold oxide platinum iron nanoparticles, which are coupled with antigens or antibodies corresponding to the target protein to be detected.

3. The fiber optic signal sensing immunoassay device as described in claim 1, characterized in that, The bare fiber segment of the sensing optical fiber is embedded in the capillary. The box body is provided with a support member on the side opposite to the embedding groove. The support member has a receiving groove. The receiving groove has an opening structure at both ends along the extension direction of the box body. The capillary tube is detachably installed in the receiving groove.

4. The fiber optic signal sensing immunoassay device as described in claim 3, characterized in that, The supporting component includes a bottom plate, a side plate, and a top plate. The first end of the bottom plate is connected to the box body, the second end of the bottom plate is connected to the bottom end of the side plate, the top end of the side plate is connected to the top plate, and a gap is formed between the end of the top plate away from the side plate and the box body. The bottom plate, side plate, and top plate cooperate to form the receiving groove with openings at both ends and the top.

5. The fiber optic signal sensing immunoassay device as described in claim 3, characterized in that, The support member has a notch in the middle so that the support member forms a segmented arrangement on the box body.

6. The fiber optic signal sensing immunoassay device according to any one of claims 1-5, characterized in that, The sensing optical fiber is wound around the outer peripheral wall of the box.

7. The fiber optic signal sensing immunoassay device as described in claim 6, characterized in that, The outer peripheral wall of the box is provided with a groove, and the sensing optical fiber can be detachably accommodated in the groove.

8. The fiber optic signal sensing immunoassay device according to any one of claims 1-5, characterized in that, The laser output end is provided with a first optical fiber connector, and the first end of the sensing optical fiber is detachably connected to the first optical fiber connector; the housing is provided with a second optical fiber connector communicating with the embedded slot, and the second end of the sensing optical fiber is detachably connected to the second optical fiber connector.

9. The fiber optic signal sensing immunoassay device according to any one of claims 1-5, characterized in that, The box body has a first fixing plate and a second fixing plate extending outward from the position corresponding to the embedding slot. The first fixing plate and the second fixing plate are arranged opposite to each other, and a slot is formed on the opposite side of the first fixing plate and the second fixing plate.

10. A fiber optic signal sensing immunoassay analyzer, characterized in that, The fiber optic signal sensing immunoassay analyzer includes a housing and a laser; the laser is disposed on the housing; the housing has an embedding slot for inserting a mobile terminal, and one side of the housing has a support for supporting a reaction container; the output end of the laser is provided with a first fiber optic connector for detachable connection with the sensing fiber; the housing is provided with a second fiber optic connector communicating with the embedding slot for detachable connection with the sensing fiber.

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