A transmission type multi-channel localized surface plasmon resonance bio-chemical analyzer

Abstract

The application discloses a transmission type multi-channel local area surface plasmon resonance biochemical analyzer and a LSPR extinction spectrum absorption peak real-time positioning algorithm based on a polynomial curve fitting, and relates to the technical field of biochemical analysis. The analyzer comprises a multi-channel spectral imaging and LSPR sensing system and a spectral data acquisition and analysis processing system. The multi-channel spectral imaging and LSPR sensing system is composed of a microfluid control and LSPR sensing system and a multi-channel spectral imaging system. The microfluid control and LSPR sensing system comprises an LSPR sensing chip, a flow cell, liquid inlet and outlet conduits, a valve, a sample inlet pump and a sensing chip stage. The multi-channel spectral imaging system comprises a light source, a collimating lens, a focusing lens, a slit, a flat-field concave grating and a plane array CCD sensor. The spectral data acquisition and analysis processing system comprises a plane array CCD sensor driving circuit, an analog-digital conversion circuit, an FPGA control circuit and an upper computer. The analyzer is compact, portable, low in cost and easy to operate.

Description

Technical Field

[0001] This invention relates to the field of biochemical analysis, and in particular to a transmission-type multichannel local surface plasmon resonance (LSPR) biochemical analyzer. It enables label-free, real-time, and rapid detection of target samples using LSPR technology. Applications include biochemical detection, disease diagnosis, environmental monitoring, and food safety. Background Technology

[0002] Biosensors play a vital role in natural sciences, including medical diagnostics, drug detection, food safety, and environmental monitoring. They convert weak interactions between biomolecules into quantifiable signal outputs, such as electrical or optical signals. Optical biosensors, in particular, offer significant advantages such as superior sensitivity, strong resistance to electromagnetic interference, miniaturization, and portability. When receptor molecules (antibodies, oligonucleotides, enzymes, etc.) interact with target analytes, real-time monitoring of molecular interactions can be achieved by measuring changes in the optical properties (intensity, wavelength, refractive index, polarization, absorption) of the output light signal from the optical biosensor. Compared to other biosensors, surface plasmon resonance (SPR)-based biosensors exhibit extremely high refractive index sensitivity, rapid response, real-time detection, and label-free operation. Localized surface plasmon resonance (LSPR) is a plasmon resonance optical phenomenon occurring on the surface of noble metal nanoparticles. In the visible light range, when incident light irradiates noble metal nanoparticles, if the incident wavelength is larger than the diameter of the metal's conduction electrons, the conduction electrons will undergo collective oscillation. When the frequency of collective electron oscillation matches the frequency of incident photons, nanoparticles will strongly absorb photon energy, causing localized surface plasmon resonance.

[0003] Traditional SPR sensors based on wavelength or angle modulation technology require complex optical structures and are significantly affected by external factors such as temperature and light source stability when detecting biological reactions. Even the BIACORE series SPR analyzers produced by GE, which has a very high market share, are mainly targeted at research institutions such as university laboratories. Their complex components, large size, and high operating costs make them unsuitable for point-of-care testing (POCT) applications.

[0004] Compared to SPR sensors, LSPR excitation does not require optical components such as prisms, thus LSPR detection systems have lower manufacturing costs and more compact structures. When biomolecules adsorb onto metal nanoparticles on an LSPR sensor chip, their surface refractive index changes, causing a shift in the absorption peak of the LSPR extinction spectrum. The change in the peak wavelength or intensity of the absorption peak is typically used as an indicator of the sensor chip's response. LSPR-based biochemical analysis systems, with their advantages of being label-free, highly resistant to interference, having high spatial resolution, and providing real-time rapid response, have become common tools for studying biomolecular interactions and are a hot research area in biochemistry, disease diagnosis, and environmental monitoring. Developing a portable, high-throughput, multi-channel localized surface plasmon resonance biochemical analyzer for real-time multi-component analysis is of significant practical importance. Summary of the Invention

[0005] The purpose of this invention is to provide a transmission-type multi-channel localized surface plasmon resonance (LSPR) biochemical analyzer, which has advantages such as temperature insensitivity, high spatial resolution, compact sensing platform, and low cost. It solves the problems of traditional SPR detection instruments, such as significant influence from temperature and buffer refractive index, complex optical structure, high operating cost, and poor anti-interference capability. The biochemical analyzer detects changes in the refractive index of the sensor chip surface by measuring the shift of the absorption peak in the LSPR extinction spectrum of metal nanoparticles. The detection optical path for the extinction spectrum is a multi-channel incident and spectral imaging coaxial optical path. Multi-channel, high-throughput detection can be achieved without moving the sensing unit, thus solving the technical difficulties of existing LSPR-based sensing systems, such as complex composition, long analysis and detection time, and low throughput.

[0006] To solve the above-mentioned technical problems, the technical solution adopted by the present invention is as follows:

[0007] A transmission-type multichannel local surface plasmon resonance biochemical analyzer includes a multichannel spectral imaging and LSPR sensing system and a spectral data acquisition and analysis processing system; the multichannel spectral imaging and LSPR sensing system consists of a microfluidic control and LSPR sensing system and a multichannel spectral imaging system.

[0008] The microfluidic control and LSPR sensing system includes an LSPR sensing chip, a flow cell, inlet and outlet conduits, valves, a sample pump, and a sensing chip stage.

[0009] The multi-channel spectral imaging system includes a light source, a collimating lens, a focusing lens, a slit, a flat concave grating, and a CCD sensor array.

[0010] The spectral data acquisition and analysis system includes a CCD sensor driving circuit, an analog-to-digital conversion circuit, an FPGA control circuit, and a host computer.

[0011] The light source is collimated by a collimating lens and shines perpendicularly onto the flow cell and the LSPR sensor chip. Stray light is then blocked by the sensor chip stage. The outgoing light passes through the collimating lens and then the focusing lens, converging at the slit. It then enters the etched area of ​​the flat-field concave grating, and after being split by the flat-field concave grating, it is focused and imaged on the area array CCD sensor. The spectral signal acquired by the area array CCD sensor is converted into an electrical signal by the area array CCD sensor driving circuit, and then transmitted to the host computer for spectral data acquisition and analysis after analog-to-digital conversion.

[0012] Preferably, the LSPR sensing chip is a metal nanoparticle array chip with a transparent glass substrate.

[0013] Preferably, the LSPR sensing chip includes a transparent glass substrate, a metal nanoparticle array, and a porous structure material; the metal nanoparticle array is directly modified on the surface of the glass substrate or first modified inside the porous structure material, and the porous structure can be a three-dimensional spatial structure formed by graphene, polydimethylsiloxane (PDMS), or hydrogel.

[0014] Preferably, the metal nanoparticles are spherical, star-shaped, columnar, or triangular in shape, and the array distribution of the metal nanoparticles is either a single distribution of one particle shape or a mixed distribution of two or more particle shapes; the diameter of the metal nanoparticles is 20-100 nm, and the material of the metal nanoparticles is gold or silver or a mixture of gold and silver.

[0015] Preferably, the light source first shines perpendicularly onto the flow cell and the LSPR sensor chip through a collimating lens, and then stray light is blocked by the sensor chip stage, allowing only the light from the two microchannel regions at the bottom of the flow cell to pass through. The outgoing light passes through the collimating lens and then converges at the slits through two focusing lenses, and then enters the flat-field concave grating etched area. After being split by the flat-field concave grating, it is focused and imaged on the area array CCD sensor, appearing as two straight spectral lines. The two microchannels at the bottom of the flow cell and the corresponding two light-transmitting channels, focusing lenses, and slits on the sensor chip stage are all located on the coaxial optical path, with the same center height.

[0016] Preferably, the flow cell covers the LSPR sensor chip structure, and the inlet / outlet conduits connect the flow cell, the injection pump, and the experimental reagents; the injection pump enables automatic injection and discharge of the experimental reagents; the sensor chip stage is made of black opaque material, allowing light to pass through only the microchannel region of the flow cell, which is used to block stray light, improve the signal-to-noise ratio, and fix the position of the LSPR sensor chip; the experimental reagents flow through the microchannels across the surface of the LSPR sensor chip; the two microchannels of the flow cell are connected, and the opening or closing of the valve selects one channel or simultaneously opens or closes both channels; the two microchannels can serve as two independent detection channels, or one channel can be used as a reference channel and the other as a detection channel; by performing differential processing on the acquired spectral results, the influence of factors such as temperature and non-specific adsorption on the detection results can be eliminated; increasing the light transmission and spectral imaging channels of the multi-channel spectral imaging system can further extend multi-component, high-throughput LSPR detection.

[0017] Preferably, the spectral signal is converted into an electrical signal by a CCD driving circuit, and after analog-to-digital conversion, the spectral data is transmitted to the host computer through a communication interface. The host computer preprocesses the spectral data to obtain the LSPR extinction spectrum, and then extracts the absorption peak wavelength or intensity information by a real-time localization algorithm for the absorption peak of the LSPR extinction spectrum based on polynomial curve fitting. This enables rapid and accurate detection of changes in the refractive index of the sensor chip surface, achieving real-time and rapid detection of biomolecular interaction processes.

[0018] Preferably, the real-time localization algorithm for the LSPR extinction spectrum absorption peak based on polynomial curve fitting includes the following steps:

[0019] Step 1: Connect the various components of the LSPR analyzer and collect the dark spectrum when there is no light input;

[0020] Step 2: Collect the reference spectrum of the blank glass substrate when the light source is outputting normally;

[0021] Step 3: Install the LSPR sensor chip and collect the real-time spectrum of the chip when the light source is outputting normally;

[0022] Step 4: Preprocess the spectral data using the spectral data acquisition and analysis system, and calculate the absorbance to obtain the LSPR extinction spectrum;

[0023] Step 5: Perform peak splitting and truncation processing on the obtained LSPR extinction spectrum to obtain discrete spectral data points near the target absorption peak;

[0024] Step 6: Perform polynomial fitting on this part of the spectral curve, and obtain the best-fit polynomial based on the least squares method.

[0025] Step 7: Find the extreme points of the fitted curve, i.e., the positions of the absorption peaks, by taking the derivative;

[0026] Step 8: Substitute the extreme points into the polynomial to obtain the peak wavelength and intensity of the extinction spectrum absorption peak, and acquire and display the position information of the absorption peak in real time.

[0027] The beneficial effects of adopting the above technical solution are as follows:

[0028] 1. The instrument is compact, portable, low-cost, and easy to operate. It requires no labeling, has high spatial resolution, requires a small amount of sample, and is less affected by external factors, making it suitable for POCT applications.

[0029] 2. By blocking stray light through the sensor chip stage, only the incident light transmitted through the effective sensing area of ​​the chip is retained, thus improving the detection signal-to-noise ratio. Through the coaxial optical path design of multi-channel incident and spectral imaging, multi-channel LSPR extinction spectrum detection can be achieved without moving the sensing unit. The detection channels can be easily expanded to achieve higher throughput multi-component LSPR parallel detection.

[0030] 3. A real-time localization algorithm for LSPR extinction spectrum absorption peaks based on polynomial curve fitting is proposed. This algorithm solves the problem of real-time localization of the peak wavelength or intensity of the extinction spectrum absorption peaks of the sensor chip, and can quickly and accurately detect changes in the refractive index of the sensor chip surface, realizing real-time and rapid detection of biomolecular interaction processes such as antigen-antibody binding and nucleic acid hybridization. Attached Figure Description

[0031] Figure 1 This is a schematic diagram of the components of a transmission-type multichannel local surface plasmon resonance biochemical analyzer;

[0032] Figure 2 This is a schematic diagram of the spectral imaging and LSPR sensing system of a multi-channel local surface plasmon resonance biochemical analyzer;

[0033] Figure 3 This is a schematic diagram of a microfluidic system and a sensor chip structure;

[0034] Figure 4 This is another schematic diagram of a microfluidic system and sensor chip structure;

[0035] Figure 5 This is a schematic diagram of microfluidic control and multi-channel LSPR sensing;

[0036] Figure 6 This is a flowchart of the real-time localization algorithm for the absorption peak of the LSPR extinction spectrum;

[0037] Figure 7 The characteristic spectral curves of light sources in different wavelength bands are measured using a multi-channel localized surface plasmon resonance biochemical analyzer.

[0038] Figure 8 It is the extinction spectrum change curve when the ambient medium of the sensor chip changes from air to water;

[0039] Figure 9 It is a real-time curve showing the change in peak wavelength and intensity of the LSPR absorption peak when the ambient medium of the sensor chip changes from air to water;

[0040] In the figure: 1. Light source; 2. First collimating lens; 3. Flow cell; 4. LSPR sensor chip; 5. Sensor chip stage; 6. Second collimating lens; 7. First focusing lens; 8. Second focusing lens; 9. First slit; 10. Second slit; 11. Flat concave grating; 12. Area array CCD sensor; 13. First microchannel; 14. Second microchannel; 15. First light transmission channel; 16. Second light transmission channel; 17. Liquid inlet conduit; 18. First liquid outlet conduit; 19. Metal nanoparticle array; 20. Transparent glass substrate; 21. Porous structural material; 22. First valve; 23. Second valve; 24. Second liquid outlet conduit. Detailed Implementation

[0041] The technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, and not all embodiments. Based on the embodiments of this application, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the scope of protection of this application.

[0042] like Figure 1 As shown, this invention designs a transmission-type multi-channel local surface plasmon resonance biochemical analyzer, including a multi-channel spectral imaging and LSPR sensing system and a spectral data acquisition and analysis processing system. The multi-channel spectral imaging and LSPR sensing system consists of a microfluidic control and LSPR sensing system and a multi-channel spectral imaging system.

[0043] Figure 2 This is a schematic diagram of a multi-channel spectral imaging and LSPR sensing system. Light source 1 is perpendicularly irradiated onto flow cell 3 and LSPR sensing chip 4 by a first collimating lens 2. Stray light from non-sensing areas is then blocked by the sensing chip stage 5. The incident light passes through the first microchannel 13 and the second microchannel 14 at the bottom of flow cell 3 and the LSPR sensing chip 4, and exits through the first light transmission channel 15 and the second light transmission channel 16, respectively. The exiting light passes through the second collimating lens 6 and then converges at the first slit 9 and the second slit 10 by the first focusing lens 7 and the second focusing lens 8, respectively. It then enters the etched area of ​​the flat-field concave grating 11, and after being split by the grating, is focused and imaged as two clear spectral lines on the area array CCD sensor 12.

[0044] Light source 1 is a wide-wavelength light source in the visible and near-infrared bands, and can be a halogen tungsten lamp or a high-power LED. The first microchannel 13 of the flow cell 3 and the first light-transmitting channel 15, first focusing lens 7, and first slit 9 of the sensor chip stage 5 are located on the coaxial optical path, with their center heights aligned. The second microchannel 14 and the second light-transmitting channel 16, second focusing lens 8, and second slit 10 of the sensor chip stage 5 are also located on the coaxial optical path. The sensor chip stage 5 is made of black opaque material, allowing only incident light from the microchannel region of the flow cell 3 to pass through, thus blocking stray light, improving the signal-to-noise ratio, and fixing the position of the sensor chip. The first microchannel 13 and the second microchannel 14 at the bottom of the flow cell 3 are independent detection channels, through which reagents flow across the surface of the sensor chip.

[0045] The CCD drive circuit of the spectral data acquisition and analysis system converts the spectral signals acquired by the area array CCD into electrical signals. After analog-to-digital conversion, the spectral data is transmitted to the host computer via a communication interface. The host computer preprocesses the spectral data to obtain the LSPR extinction spectrum, and then extracts the absorption peak wavelength or intensity information using a real-time absorption peak localization algorithm based on polynomial curve fitting. This allows for rapid and accurate detection of changes in the refractive index of the sensor chip surface.

[0046] like Figure 3 As shown, the LSPR sensor chip 4 has a two-layer structure: a transparent glass substrate 20 and a metal nanoparticle array 19, from bottom to top. The chip structure is a two-dimensional planar structure. The metal nanoparticle array 19 is applied to the transparent glass substrate 20. The metal nanoparticles are spherical, star-shaped, columnar, or triangular in shape. The distribution of the metal nanoparticle array 19 can be a single distribution of one particle shape or a mixed distribution of two or more particle shapes. The diameter of the metal nanoparticles is 20-100 nm, and the material of the metal nanoparticles is gold, silver, or a mixture of both.

[0047] As a further improvement to the LSPR sensor chip structure, such as Figure 4As shown, the LSPR sensor chip 4 has a three-layer structure, from bottom to top: a transparent glass substrate 20, a metal nanoparticle array 19, and a porous material 21. The chip structure is a three-dimensional structure. The metal nanoparticle array 19 is modified inside the porous material 21, which can be graphene, polydimethylsiloxane (PDMS), hydrogel, etc. Compared with planar structures, the porous structure has a larger specific surface area, which can bind more metal nanoparticles and effectively improve the adsorption capacity for target biomolecules, thereby improving the sensing performance and detection signal-to-noise ratio of the LSPR chip. The flow cell 3 covers the LSPR sensor chip 4 structure. Experimental reagents are driven by a sample pump, entering the first microchannel 13 of the flow cell 3 from the inlet conduit 17, flowing through the surface of the sensor chip 4, and finally exiting from the first outlet conduit 18.

[0048] like Figure 5 As shown, the first microchannel 13 and the second microchannel 14 of the flow cell 3 are connected by tubing. By opening or closing the first valve 22 and the second valve 23, one channel can be selected, or both channels can be opened or closed simultaneously. When the first valve 22 is opened and the second valve 23 is closed, the experimental reagent enters the first microchannel 13 from the inlet conduit 17 and exits from the first outlet conduit 18. When the second valve 23 is opened and the first valve 22 is closed, the experimental reagent enters the second microchannel 14 from the inlet conduit 17 and exits from the second outlet conduit 24. In this case, the two microchannels can function as two independent detection channels.

[0049] When monitoring biomolecular interactions such as antigen-antibody binding, one channel can be used as a reference channel and the other as a detection channel. Introducing a reference channel can eliminate the influence of factors such as temperature and non-specific adsorption on the detection results. First, the first valve 22 and the second valve 23 are opened simultaneously, and an activation reagent is injected through the inlet conduit 17. The reagent is discharged through the first outlet conduit 18 and the second outlet conduit 24. Then, the second valve 23 is closed, and the first valve 22 is opened, injecting a ligand reagent through the inlet conduit 17. The ligand is fixed on the surface of the chip sensing area corresponding to the first microchannel 13 through a biochemical reaction, and the reagent is discharged through the first outlet conduit 18. Next, the first valve 22 and the second valve 23 are opened simultaneously, injecting a blocking reagent to block the activation sites on the surface of the LSPR sensing chip 4, preventing non-specific binding. Finally, the first valve 22 and the second valve 23 are opened simultaneously, injecting a target molecule reagent. The absorption peak wavelength or intensity information is obtained through a real-time localization algorithm based on polynomial curve fitting of the LSPR extinction spectrum absorption peak, thereby quickly and accurately detecting the change in refractive index on the sensing chip surface caused by the binding of the ligand and the target molecule. The first microchannel 13 serves as the detection channel, and the microchannel 14 serves as the reference channel. The wavelength or intensity data of the absorption peaks corresponding to the first microchannel 13 and the first microchannel 14 are differentially processed to obtain the final detection result. This can eliminate the influence of factors such as temperature and non-specific adsorption on the detection result. As a further extension of multi-component, high-throughput LSPR detection, the transmission and spectral imaging channels of the multi-channel spectral imaging system can be increased.

[0050] like Figure 6 The algorithm shown is a real-time localization algorithm for the absorption peak of the LSPR extinction spectrum based on polynomial curve fitting. It includes the following steps:

[0051] Step 1: Connect the various components of the LSPR analyzer and collect the dark spectrum when there is no light input;

[0052] Step 2: Collect the reference spectrum of the blank glass substrate when the light source is outputting normally;

[0053] Step 3: Install the LSPR sensor chip and collect the real-time spectrum of the chip when the light source is outputting normally;

[0054] Step 4: Preprocess the spectral data using the spectral data acquisition and analysis system, and calculate the absorbance to obtain the LSPR extinction spectrum;

[0055] Step 5: Perform peak splitting and truncation processing on the obtained LSPR extinction spectrum to obtain discrete spectral data points near the target absorption peak;

[0056] Step 6: Perform polynomial fitting on this part of the spectral curve, and obtain the best-fit polynomial based on the least squares method.

[0057] Step 7: Find the extreme points of the fitted curve, i.e., the positions of the absorption peaks, by taking the derivative;

[0058] Step 8: Substitute the extreme points into the polynomial to obtain the peak wavelength and intensity of the extinction spectrum absorption peak, and acquire and display the position information of the absorption peak in real time.

[0059] This algorithm can solve the problem of real-time positioning of the peak wavelength or intensity of the extinction spectrum absorption peak of the sensor chip, and can quickly and accurately detect changes in the refractive index of the sensor chip surface.

[0060] Figure 7 These are characteristic spectral curves obtained by using a multi-channel local surface plasmon resonance biochemical analyzer when light sources of different wavelengths are used as incident light. The spectral intensity signals were normalized for easier comparison.

[0061] Researchers used this invention to measure the changes in the LSPR extinction spectrum and the real-time changes in the position and intensity of the absorption peaks when the ambient medium of the sensor chip changed from air (refractive index n=1) to water (refractive index n=1.333). First, a blank transparent glass substrate without metal nanoparticle modification was mounted on the sensor chip stage. Deionized water was injected into the microchannel of the flow cell using a sample pump, and the dark spectrum without light source input was collected and saved. Then, a halogen tungsten lamp was turned on, and the transmission spectrum of the blank substrate was collected as a reference spectrum. The blank substrate was removed, and an LSPR sensor chip modified with a metal nanoparticle array was installed. The real-time spectrum when the ambient medium of the sensor chip was air was measured. The spectral data was preprocessed using a spectral data acquisition and analysis system, and the absorbance was calculated to obtain the LSPR extinction spectrum of the sensor chip. After a period of time, deionized water was injected into the microchannel of the flow cell via a sample injection pump. Similarly, the LSPR extinction spectrum was obtained when the ambient medium of the sensor chip was water. Using a real-time LSPR extinction spectrum absorption peak localization algorithm, the peak wavelength and intensity change curves of the sensor chip's absorption peaks could be obtained as the ambient medium changed from air to water. The results are as follows: Figure 8 , Figure 9 As shown.

[0062] The spectral data acquisition and analysis system can acquire information on the peak wavelength or intensity changes of the absorption peak of the sensor chip in real time, thereby quickly and accurately detecting changes in the refractive index of the sensor chip surface and realizing real-time rapid detection of biomolecular interaction processes.

[0063] The above are merely preferred embodiments of the present invention, but the scope of protection of the present invention is not limited thereto. Any equivalent substitutions or modifications made by those skilled in the art within the scope of the technology disclosed in the present invention, based on the technical solution and inventive concept of the present invention, should be covered within the scope of protection of the present invention.

Claims

1. A transmission-type multi-channel localized surface plasmon resonance biochemical analyzer, characterized in that, It includes a multi-channel spectral imaging and LSPR sensing system and a spectral data acquisition and analysis system. The multi-channel spectral imaging and LSPR sensing system consists of a microfluidic control and LSPR sensing system and a multi-channel spectral imaging system. The microfluidic control and LSPR sensing system includes an LSPR sensing chip, a flow cell, inlet and outlet conduits, valves, a sample pump, and a sensing chip stage. The multi-channel spectral imaging system includes a light source, a collimating lens, a focusing lens, a slit, a flat concave grating, and a CCD sensor array. The spectral data acquisition and analysis system includes a CCD sensor driving circuit, an analog-to-digital conversion circuit, an FPGA control circuit, and a host computer. The light source is collimated by a collimating lens and shines perpendicularly onto the flow cell and the LSPR sensor chip. Stray light is then blocked by the sensor chip stage. The outgoing light passes through the collimating lens and then the focusing lens, converging at the slit before entering the etched area of ​​the flat-field concave grating. After being split by the flat-field concave grating, the light is focused onto the area CCD sensor for imaging. The spectral signal acquired by the area CCD sensor is converted into an electrical signal by the area CCD sensor driving circuit, and then transmitted to the host computer for spectral data acquisition and analysis after analog-to-digital conversion. The two microchannels at the bottom of the flow cell, the corresponding two light-transmitting channels on the sensor chip stage, the focusing lens, and the slit are all located on the coaxial optical path with the same center height. The two microchannels of the flow cell are connected, and the opening or closing of the valve selects one channel or opens or closes both channels simultaneously.

2. The transmission-type multi-channel localized surface plasmon resonance biochemical analyzer according to claim 1, characterized in that, The LSPR sensing chip is a metal nanoparticle array chip with a transparent glass substrate.

3. The transmission-type multi-channel localized surface plasmon resonance biochemical analyzer according to claim 1, characterized in that, The LSPR sensing chip includes a transparent glass substrate, a metal nanoparticle array, and a porous structure material. The metal nanoparticle array is directly modified on the surface of the glass substrate or first modified inside the porous structure material. The porous structure is a three-dimensional spatial structure formed by graphene, polydimethylsiloxane (PDMS), and hydrogel.

4. A transmission-type multi-channel localized surface plasmon resonance biochemical analyzer according to claim 2 or 3, characterized in that, The metal nanoparticles are spherical, star-shaped, columnar, or triangular in shape, and the metal nanoparticle array is distributed as a single distribution of one particle shape or a mixed distribution of two or more particle shapes; the diameter of the metal nanoparticles is 20-100 nm, and the material of the metal nanoparticles is gold or silver or a mixture of gold and silver.

5. A transmission-type multi-channel localized surface plasmon resonance biochemical analyzer according to claim 1, characterized in that, The light source first shines perpendicularly onto the flow cell and LSPR sensor chip through a collimating lens. Then, stray light is blocked by the sensor chip stage, allowing only the light from the two microchannel regions at the bottom of the flow cell to pass through. After passing through the collimating lens, the outgoing light is converged at the slits by two focusing lenses, and then incident on the flat concave grating etched area. After being split by the flat concave grating, the light is focused and imaged on the area array CCD sensor, appearing as two straight spectral lines.

6. The transmission-type multi-channel localized surface plasmon resonance biochemical analyzer according to claim 1, characterized in that, The flow cell covers the LSPR sensor chip structure, and the inlet / outlet conduits connect the flow cell, the injection pump, and the experimental reagents. The injection pump enables automatic injection and discharge of the experimental reagents. The sensor chip stage is made of a black, opaque material, allowing light to pass through only the microchannel region of the flow cell. This serves to block stray light, improve the signal-to-noise ratio, and fix the position of the LSPR sensor chip. The experimental reagents flow through the microchannels across the surface of the LSPR sensor chip. The two microchannels serve as two independent detection channels, or one channel can be used as a reference channel and the other as a detection channel. Differential processing of the acquired spectral results eliminates the influence of temperature and non-specific adsorption factors on the detection results. Adding transmittance and spectral imaging channels to the multi-channel spectral imaging system further extends multi-component, high-throughput LSPR detection.

7. A transmission-type multi-channel localized surface plasmon resonance biochemical analyzer according to claim 1, characterized in that, The spectral signal is converted into an electrical signal by the CCD driving circuit. After analog-to-digital conversion, the spectral data is transmitted to the host computer through the communication interface. The host computer preprocesses the spectral data to obtain the LSPR extinction spectrum. Then, the absorption peak wavelength or intensity information is extracted by the real-time localization algorithm of the LSPR extinction spectrum absorption peak based on polynomial curve fitting. This allows for rapid and accurate detection of changes in the refractive index of the sensor chip surface, enabling real-time and rapid detection of biomolecular interaction processes.

8. A transmission-type multi-channel localized surface plasmon resonance biochemical analyzer according to claim 7, characterized in that, The real-time localization algorithm for the LSPR extinction spectrum absorption peak based on polynomial curve fitting includes the following steps: S1: Connects to the various components of the LSPR analyzer to collect dark spectra when there is no light input; S2: Collect the reference spectrum of the blank glass substrate when the light source is outputting normally; S3: Install an LSPR sensor chip to collect the chip's real-time spectrum when the light source is outputting normally; S4: The spectral data is preprocessed through the spectral data acquisition and analysis system, and the absorbance is calculated to obtain the LSPR extinction spectrum; S5: Perform peak segmentation and amplitude truncation on the acquired LSPR extinction spectrum to obtain discrete spectral data points near the target absorption peak; S6: Perform polynomial fitting on this part of the spectral curve, and obtain the best-fit polynomial by solving the least squares method. S7: Find the extreme points of the fitted curve, i.e., the positions of the absorption peaks, by taking the derivative; S8: Substitute the extreme points into the polynomial to obtain the peak wavelength and intensity of the extinction spectrum absorption peak, and acquire and display the position information of the absorption peak in real time.

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