Portable double-path optical field detection device and method based on paper chip

Abstract

The invention provides a portable double-path optical field detection device and method based on a paper chip, and the device comprises a hollow portable detection cassette main body, image collection equipment, a colorimetric detection system, a fluorescence detection system, a paper chip fixing device, and a temperature and humidity control device. A hole is formed in a top cover of the portable detection cassette main body and used for being matched with image acquisition equipment, the colorimetric detection system, the fluorescence detection system and the temperature and humidity control device are arranged in the portable detection cassette main body, and the paper chip fixing device is detachably arranged at the bottom of the portable detection cassette main body. According to the invention, the stability problem of color development reaction on the paper chip, the stability problem of image acquisition and the problem of high detection limit are solved, so that an accurate and reliable analysis result is ensured to be obtained.

Description

Technical Field

[0001] This invention belongs to the field of field testing technology and relates to a portable dual-path optical field testing device and method based on paper chips. Background Technology

[0002] On-site detection technology based on paper-based microfluidic chips (μPADs) has shown great application potential in many fields such as disease diagnosis, environmental monitoring, and food safety due to its significant advantages such as low cost, high portability, and rapid response. Currently, this technology mainly relies on analyzing the grayscale values ​​of colorimetric reaction images on the paper chip to achieve quantitative detection. In the entire process from colorimetric reaction to image analysis, the stability of the colorimetric reaction on the paper chip and the standardization and stability of image acquisition are key factors determining the reliability of the quantitative analysis results.

[0003] Currently, most paper-based chips employ an open design, leading to significant variations in colorimetric reaction results under different environmental conditions, severely impacting the stability of the colorimetric reaction. In the image acquisition stage, the mainstream method relies on smartphone photography; however, fluctuations in ambient light intensity, differences in equipment performance, and insufficient standardization of operations all interfere with the stability of the colorimetric images. Furthermore, existing detection methods are relatively limited, often confined to a single method such as colorimetry, fluorescence, or electrochemical methods, resulting in a lack of versatility in overall on-site detection devices and an inability to meet diverse detection needs.

[0004] The solution lies in addressing the issue of poor stability of color development reactions under different environmental conditions caused by the open design of paper-based field testing platforms; eliminating interference from ambient light intensity fluctuations, equipment differences, and insufficient operational standardization during image acquisition on the stability of color images; and simultaneously overcoming the limitations of existing single testing methods to improve the versatility of field testing devices and achieve multi-functional testing. Summary of the Invention

[0005] To address the problems existing in the prior art, this invention provides a portable dual-path optical field inspection device and method based on paper chips. It solves the problems of stability of color development reaction on paper chips, stability of image acquisition, and detection height limit in current field inspection platforms based on paper chips, thereby ensuring accurate and reliable analysis results.

[0006] To achieve the above objectives, the present invention provides the following technical solution: a portable dual-path optical field inspection device based on paper chips, comprising a hollow portable inspection dark box body, an image acquisition device, a colorimetric detection system, a fluorescence detection system, a paper chip fixing device, and a temperature and humidity control device. The top cover of the portable inspection dark box body has a hole for matching the image acquisition device. The colorimetric detection system, the fluorescence detection system, and the temperature and humidity control device are disposed inside the portable inspection dark box body. The paper chip fixing device is detachably disposed at the bottom of the portable inspection dark box body.

[0007] Furthermore, the portable detection cassette body is manufactured using 3D printing, made of black ABS or PLA material, and the inner wall is matte-finished; a sealing strip is provided between the top cover of the portable detection cassette body and the portable detection cassette body; a light-proof baffle is provided inside the portable detection cassette body.

[0008] Furthermore, the image acquisition device is a fixed portable camera, and the shooting distance is a fixed height of the portable detection cassette body. After the portable camera acquires the image, the image data is processed, including grayscale conversion, threshold segmentation and color analysis, to obtain the quantitative analysis results of the analyte. Furthermore, the portable testing cassette has holes on its top cover to serve as a placement area for the camera of the image acquisition device. The shape of the placement area is adapted to accommodate cameras of different shapes, and a rubber gasket is set on the inner side of the placement area.

[0009] Furthermore, the colorimetric detection system includes an illumination source, which is located on the top, side, or bottom of the portable detection cassette body, and the illumination source is an LED light source or an incandescent lamp.

[0010] Furthermore, the geometric center of the lighting source coincides with the center of the paper chip placement area.

[0011] Furthermore, the fluorescence detection system includes a fluorescence excitation source, which is either a uniform fluorescence excitation source or a focused fluorescence excitation source.

[0012] Furthermore, when using a uniform fluorescence excitation source, the fluorescence excitation source is located on the top of the portable detection cassette body and also includes a filter, which is set in front of the camera of the image acquisition device. When used as a focused fluorescence excitation source, the fluorescence excitation source is located on the side of the portable detection cassette body. The source outlet is placed at an angle of 20° to 90° to the bottom of the portable detection cassette body. It also includes two lenses and a filter. The filter size matches the lens. The filter is fixed between the two lenses by a snap-on filter holder. The filter holder can be pulled out and replaced.

[0013] Furthermore, the paper chip fixing device includes a paper chip placement area, the center of which is a solid square for supporting the paper-based microfluidic chip, and a snap-fit ​​structure is provided around the paper chip placement area to fix the paper-based microfluidic chip on the paper chip placement area; The temperature and humidity control device is a temperature and humidity control box, which mainly contains desiccant, humidifier, and temperature control equipment to control the temperature and humidity of the paper chip reaction in the paper chip placement area.

[0014] This invention also provides a portable dual-path optical field inspection method based on paper chips, which employs the aforementioned portable dual-path optical field inspection device based on paper chips, as detailed below: Set the image acquisition device on the top cover of the portable detection cassette and align it with the paper chip placement area. The paper-based microfluidic chip is placed on the paper chip fixing device and fixed to the bottom of the portable detection dark box body; When the concentration of the analyte is high, the colorimetric detection system is turned on, and the image acquisition device acquires the image of the paper-based microfluidic chip detected by colorimetry. The image is then processed to obtain the quantitative analysis results. When the concentration of the analyte is low, the fluorescence detection system is turned on, and the image acquisition device acquires the image of the paper-based microfluidic chip detected by fluorescence method. The image is then processed to obtain the quantitative analysis results.

[0015] Compared with the prior art, the present invention has at least the following beneficial effects: This invention provides a portable dual-path optical on-site inspection device based on paper chips. By creating a hole in the top cover of the portable inspection cassette and matching it with an image acquisition device, and by setting a paper chip fixing device at the bottom of the portable inspection cassette, the image detection distance is kept constant. Furthermore, by setting a colorimetric detection system inside the portable inspection cassette, the light intensity is kept constant, ensuring the stability of colorimetric image acquisition. In addition, this invention also equips the main body with a fluorescence detection system, which, together with the detachable paper chip fixing device at the bottom of the portable inspection cassette, enables dual detection of the paper chip. This overcomes the limitation of existing technologies that can only perform single colorimetric detection, and also solves the problem of height limitation in colorimetric detection, meeting the needs of multi-dimensional detection in different detection scenarios and greatly expanding the application range of the device.

[0016] Furthermore, this invention utilizes a camera to capture images of the paper chip and combines this with built-in parameters to perform precise processing and analysis of the image data, achieving accuracy and real-time performance in colorimetric detection. Simultaneously, the combined use of LED lights and a fluorescent excitation light source further enhances the reliability and accuracy of the detection.

[0017] Furthermore, the paper chip fixing device of the present invention is detachably installed at the bottom of the portable detection dark box body, and the temperature and humidity control area enables precise control of the paper chip reaction environment, which is beneficial to improving the sensitivity and accuracy of detection.

[0018] Furthermore, this invention uses 3D printing to prepare the portable detection cassette body, top cover, and paper chip fixing device. The structure is reasonably designed, and the components fit together tightly, which improves the overall performance and service life of the equipment. Attached Figure Description

[0019] Figure 1 This is a schematic diagram of a portable detection cassette that uses both colorimetric and fluorescence methods for dual-path detection. The fluorescence light source is uniform fluorescence excitation light. Figure 2 This is a schematic diagram of a portable detection cassette that uses both colorimetric and fluorescence methods for dual-channel detection. The fluorescence light source employs focused fluorescence excitation light. Figure 3 This is a schematic diagram of fluorescence detection using a uniformly excited light source; Figure 4 This is a schematic diagram of fluorescence detection using a focused excitation source; Figure 5 These are the results of fluorescence and colorimetric detection; a(1) and a(2) are for a concentration of 10 -2 Images of sodium fluorescein solution (1 mol / L) dropped onto a paper chip under uniform fluorescence excitation and LED bright field conditions; b(1) and b(2) are images of sodium fluorescein solution (1 mol / L) dropped onto a paper chip under uniform fluorescence excitation and LED bright field conditions. - 3 Images of sodium fluorescein solution (mol / L) dropped onto a paper chip under uniform fluorescence excitation and LED bright field conditions; c(1) and c(2) are images of sodium fluorescein solution (mol / L) with a concentration of 10 mol / L. -4 Images of sodium fluorescein solution (mol / L) dropped onto a paper chip under uniform fluorescence excitation light and LED bright field conditions.

[0020] In the figure, 1. Portable detection dark box main body; 2. Image acquisition device; 3. Illumination source; 4. Fluorescent excitation source; 5. Paper-based microfluidic chip; 6. Paper chip placement area; 7. Temperature and humidity control box; 8. Camera; 9. Filter; 10. Lens. Detailed Implementation

[0021] In the following description, only certain exemplary embodiments are briefly described. As those skilled in the art will recognize, the described embodiments can be modified in various ways without departing from the spirit or scope of the invention. Therefore, the drawings and description are considered to be exemplary in nature and not restrictive.

[0022] In the description of this invention, it should be understood that the terms "center," "longitudinal," "lateral," "length," "width," "thickness," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," "outer," "clockwise," "counterclockwise," "axial," "radial," and "circumferential" indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are used only for the convenience of describing this invention and simplifying the description, and 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. Therefore, they should not be construed as limitations on this invention.

[0023] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of indicated technical features. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of that feature. In the description of this invention, "a plurality of" means two or more, unless otherwise explicitly specified.

[0024] In this invention, unless otherwise explicitly specified and limited, the terms "installation," "connection," "linking," and "fixing," etc., should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; they can refer to a mechanical connection, an electrical connection, or a communication connection; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components. Those skilled in the art can understand the specific meaning of the above terms in this invention according to the specific circumstances.

[0025] In this invention, unless otherwise explicitly specified and limited, "above" or "below" the second feature can include direct contact between the first and second features, or contact between the first and second features through another feature between them. Furthermore, "above," "over," and "on top" of the second feature includes the first feature being directly above or diagonally above the second feature, or simply indicates that the first feature is at a higher horizontal level than the second feature. "Below," "below," and "under" the second feature includes the first feature being directly above or diagonally above the second feature, or simply indicates that the first feature is at a lower horizontal level than the second feature.

[0026] The embodiments of the present invention will now be described in detail with reference to the accompanying drawings.

[0027] like Figures 1-2As shown, the present invention provides a portable dual-path optical field inspection device based on paper chips, including a hollow portable inspection dark box body 1, an image acquisition device 2, a colorimetric detection system, a fluorescence detection system, a paper chip fixing device, and a temperature and humidity control device. The portable inspection dark box body 1 has a hole on its top cover for matching the image acquisition device 2. The colorimetric detection system, the fluorescence detection system, and the temperature and humidity control device are disposed inside the portable inspection dark box body 1. The paper chip fixing device is detachably disposed at the bottom of the portable inspection dark box body 1.

[0028] Preferably, the colorimetric detection system includes an illumination source 3, which can be an LED light source or an incandescent lamp. The shape can be ring-shaped or two independent light sources. It is also equipped with diffuse reflection materials such as light-shielding cloth to obtain uniform light. It can be set on the top, side or bottom of the portable detection dark box body 1, as long as the light environment is stable and does not affect the acquisition of raw data by the image acquisition device 2.

[0029] Preferably, the LED light source uses four high-brightness surface-mount LEDs of the same model, which are symmetrically distributed in a square shape on the bottom of the top cover of the portable detection box body 1. The geometric center of the four LEDs coincides with the center of the paper chip placement area 6, ensuring that the light uniformly covers the detection area of ​​the paper-based microfluidic chip 5.

[0030] Preferably, white LEDs (color temperature 5500K-6500K, close to natural light) are selected, with a rated voltage of 3.3V, a rated current of 20mA, and a single LED luminous intensity of ≥80lm. The current is controlled to stabilize by a series current-limiting resistor (resistance value 100Ω) to avoid overexposure of strong light or underexposure of weak light affecting the accuracy of grayscale values ​​of the color image.

[0031] Preferably, the LED light is surface-mounted onto the PCB substrate, and the PCB substrate is fixed with screws in a pre-set groove at the bottom of the top cover (groove depth 2mm, adapted to the thickness of the PCB board), ensuring that the light-emitting surface of the LED light is flush with the bottom of the top cover and there is no light obstruction.

[0032] The fluorescence detection system includes a fluorescence excitation source 4 for fluorescence detection of a paper-based microfluidic chip 5. The fluorescence excitation source 4 is fixed in the portable detection dark box body 1 by a metal bracket, which can rotate around a horizontal axis. Preferably, the fluorescence excitation source 4 provides an excitation source for the fluorescent material on the paper-based microfluidic chip 5. The excitation light is then filtered out by the filter 9. Finally, the fluorescence signal emitted by the fluorescent material is collected by the image acquisition device 2 as the detection basis. According to common fluorescence detection requirements, the fluorescence excitation source 4 can be a uniform fluorescence excitation source or a focused fluorescence excitation source. The two sources require different optical path systems. The uniform excitation source has fewer optical path systems and components and is simpler to operate. However, due to the relatively weak light intensity, the detection limit is higher than that of the focused fluorescence source.

[0033] The optical path system of the uniform fluorescence excitation source is as follows: Figure 3 As shown, the fluorescence excitation source 4 can be located on the top of the portable detection cassette. A filter 9 is placed in front of the camera 8 of the image acquisition device 2 to filter out the light emitted by the excitation source 4, thus obtaining accurate image data. Figure 5 As shown in a.

[0034] The characteristic of a focused fluorescence excitation source is that the intensity is high at the center and weak at the periphery. Therefore, to ensure that the center of the light source precisely illuminates the detection area of ​​the paper-based microfluidic chip 5, a lower detection limit can be obtained. However, this method is more expensive and more difficult to operate than a uniform excitation source. The optical path system of the focused fluorescence excitation source is as follows: Figure 4 As shown, the position of the fluorescence excitation light source 4 should be placed on the side of the portable detection box body 1, and the light source outlet should be placed at an angle of 20°~90° with the bottom of the portable detection box body 1, so that the center of the light source can just illuminate the fluorescent material in the detection area of ​​the paper-based microfluidic chip 5. Then, two lenses 10 and a filter 9 are added in front of the camera 8 of the image acquisition device 2 to obtain the fluorescence signal, so as to obtain the original image data with a lower detection limit.

[0035] Preferably, the size of the filter 9 matches that of the lens 10. The filter 9 is fixed between the two lenses 10 by a snap-on filter holder. The filter holder can be pulled out and replaced, which makes it easy to replace the corresponding filter according to different fluorescent probes and improves the versatility of the device.

[0036] Preferably, lens 10 is a plano-convex lens with a diameter of 15mm and a focal length of 20mm. It is made of optical-grade PMMA (transmittance ≥92%) and has an anti-reflection coating on its surface (for wavelengths between 400nm and 700nm). This coating can focus the divergent fluorescence signal emitted by the paper-based microfluidic chip 5 into parallel light, improving signal intensity. Lens 10 is fixed inside a metal mount, which is then secured to a pre-set lens bracket inside the portable detection cassette body 1 using screws. The central axis of lens 10 is perfectly aligned with the optical axis of camera 8 and the center of the detection area of ​​paper-based microfluidic chip 5 (coaxiality error ≤0.3mm), ensuring that the focused fluorescence signal can fully enter the camera lens.

[0037] Preferably, the filter 9 is a bandpass filter, and the filter parameters are matched according to the wavelength of the excitation source (e.g., a 525nm±15nm bandpass filter corresponds to a 470nm excitation source). This allows the specific wavelength fluorescence signal emitted by the paper-based microfluidic chip 5 to pass through (transmittance ≥85%), while blocking unabsorbed excitation light (cutoff depth OD4, i.e., excitation light transmittance ≤0.01%), thus reducing background interference.

[0038] Preferably, the portable detection box body 1 is provided with a sliding groove at the bottom, and the paper chip fixing device can be slidably fixed to the bottom of the portable detection box body 1 through the sliding groove. The paper chip fixing device is provided with a paper chip placement area 6, which is designed to be a solid square in the middle for holding the paper chip. The paper chip fixing device also includes a snap-fit ​​structure for fixing the paper chip to the paper chip placement area 6.

[0039] The temperature and humidity control device, namely the temperature and humidity control box 7, mainly contains desiccant, humidifier, and temperature control equipment, and is used to control the temperature and humidity of the paper chip reaction in the paper chip placement area 6.

[0040] Preferably, the temperature and humidity control box 7 mainly uses a desiccant and a mini humidifier to regulate the ambient humidity, and ice packs and hand warmers to regulate the ambient temperature. It is selected for use in extreme environmental conditions (ambient relative humidity greater than 60% or less than 20%, temperature below 15℃ or above 30℃).

[0041] Preferably, the temperature and humidity control box 7 controls the paper-based microfluidic chip under test to be kept at a temperature of 15℃-30℃ and a humidity of 20%-80%, resulting in good reproducibility of quantitative analysis results.

[0042] Preferably, the portable detection dark box body 1, the top cover of the portable detection dark box body 1, and the paper chip fixing device are prepared by 3D printing.

[0043] Preferably, the portable detection dark box body 1, the top cover of the portable detection dark box body 1, and the paper chip fixing device can all be made of 3D printing materials such as ABS (acrylonitrile-butadiene-styrene copolymer), PLA (polylactic acid), PETG (polyethylene terephthalate), TPU / TPE (thermoplastic polyurethane / thermoplastic elastomer), nylon (PA), and PC (polycarbonate).

[0044] Preferably, the portable detection dark box body 1 is mainly designed to ensure the stability of the light environment during the detection process. It is 3D printed from black ABS material (3mm wall thickness), and the inner wall is matte-finished (surface roughness Ra≤0.8μm), which can absorb more than 90% of stray light and prevent light from reflecting and forming light spots inside the dark box. A sponge sealing strip (5mm wide and 2mm thick) is set at the connection between the top cover and the portable detection dark box body 1. When closed, it can achieve light sealing, blocking external ambient light (such as indoor lighting and natural light) from entering the dark box. This ensures that the light inside the dark box is provided only by LED lights during colorimetric detection, and the influence of ambient light fluctuations is reduced to within ±2%.

[0045] Preferably, the portable detection cassette body 1 is also equipped with a light shield inside to prevent interference from external light.

[0046] Preferably, the vertical distance from the illumination source 3 to the paper chip placement area 6 is fixed, and the thickness of the paper chip fixing device is fixed, thereby ensuring that the object distance between the camera 8 and the paper chip detection surface remains constant under different detection scenarios, and avoiding differences in image scaling ratio due to changes in distance.

[0047] Preferably, the image acquisition device 2 is a fixed portable camera, and the shooting distance is a fixed height of the portable detection dark box body 1 to ensure the stability of the acquired original image data.

[0048] Preferably, the image acquisition device 2 converts the acquired image data into grayscale information and provides quantitative analysis results, which is accomplished using image analysis and processing software on a smartphone. First, the image is transferred to the smartphone via a data cable or wireless network. The original image acquired by the image acquisition device 2 is then transferred to the smartphone, where the image processing and analysis software or app analyzes it to obtain the corresponding grayscale value and provides quantitative analysis results based on the software's built-in standard curve data.

[0049] This invention addresses the reaction conditions on the paper-based microfluidic chip 5 by proposing the inclusion of a temperature and humidity control box within the portable detection cassette body 1. This controls the environmental conditions for the colorimetric reaction on the paper-based microfluidic chip 5, improving the reproducibility and accuracy of the original data. Secondly, by controlling the intensity and position of the illumination source 3, a stable lighting environment and uniform shooting distance are provided for image data acquisition, avoiding the impact of changes in the lighting environment on the image data during acquisition. Finally, an image acquisition device 2 (portable camera) is used to avoid the influence of different data acquisition devices on the detection results.

[0050] To address the issue of high detection limits in colorimetric methods, this invention proposes a dual-path detection system combining colorimetry and fluorescence detection, and preliminarily verifies the feasibility of this approach. When the analyte concentration is high, the colorimetric detection system is used; when the concentration is low, the fluorescence detection system is employed.

[0051] The steps for colorimetric testing are as follows: Step 1: Place the image acquisition device 2 on the top cover of the portable detection box body 1, and place the camera 8 in the hole on the top cover. Make sure that the camera 8 can be vertically facing the area below, and ensure that the distance between the camera 8 and the paper-based microfluidic chip 5 is consistent during each detection to avoid affecting the stability of image acquisition due to changes in distance. Step 2: Next, prepare the paper-based microfluidic chip 5. Place the paper-based microfluidic chip 5 to be tested stably in the paper chip placement area 6, and gently press the edge of the paper-based microfluidic chip 5 to fix it in place and prevent displacement during the testing process. Then check the closure status of the portable testing box body 1, and tightly close the top cover to ensure that the inside of the box is a closed environment, minimizing the interference of external light on the testing. Step 3: Then turn on the colorimetric detection components and turn on the illumination source 3. The LED light will continuously provide stable illumination, which will evenly illuminate the paper-based microfluidic chip 5, providing a standard light environment for colorimetric detection. Step 4: After the colorimetric reaction on the paper-based microfluidic chip 5 stabilizes, use the fixed camera 8 to capture a colorimetric image of the paper-based microfluidic chip 5. After capturing the image, transmit the image data acquired by the camera 8 to a smartphone APP. In the smartphone APP, the image is first converted into grayscale values, then the grayscale values ​​are further converted into digital form for output. Finally, combined with the built-in colorimetric detection parameters, the quantitative analysis results of the analyte are calculated and displayed.

[0052] The steps for fluorescence detection are as follows: Step 1: Place the image acquisition device 2 on the top cover of the portable detection box body 1, and place the camera 8 in the hole on the top cover. Make sure that the camera 8 can be vertically facing the area below, and ensure that the distance between the camera 8 and the paper-based microfluidic chip 5 is consistent during each detection to avoid affecting the stability of image acquisition due to changes in distance. Step 2: Next, prepare the paper-based microfluidic chip 5. Place the paper-based microfluidic chip 5 to be tested stably in the paper chip placement area 6, and gently press the edge of the paper-based microfluidic chip 5 to fix it in place and prevent displacement during the testing process. Then check the closure status of the portable testing box body 1, and tightly close the top cover to ensure that the inside of the box is a closed environment, minimizing the interference of external light on the testing. Step 3: Then turn on the fluorescence detection components and turn on the fluorescence excitation light source 4. The fluorescence excitation light source 4 continuously excites the fluorescent reaction material on the paper-based microfluidic chip 5. Step 4: After the fluorescence reaction stabilizes, use the fixed camera 8 to capture an image of the paper-based microfluidic chip 5. After capturing the image, transfer the data from the camera 8 to a smartphone app. In the app, the image is first converted to grayscale, then further converted to digital format for output. Finally, combined with the corresponding detection parameters, the quantitative analysis results of the analyte are obtained and displayed.

[0053] like Figure 5 As shown, taking a uniform fluorescence excitation source as an example, when the concentration of sodium fluorescein is 10... -2 At a concentration of mol / L, image data can be acquired using colorimetry, while fluorescence methods result in excessively strong light signals. However, when the concentration of sodium fluorescein is reduced to 10... - 4 At a concentration of mol / L, colorimetry cannot detect the signal, but fluorescence can. Therefore, dual-channel detection can be selected as needed in practical applications.

[0054] The foregoing has shown and described the basic principles, main features, and advantages of the present invention. It will be apparent to those skilled in the art that the invention is not limited to the details of the exemplary embodiments described above, and that the invention can be implemented in other specific forms without departing from its spirit or essential characteristics. Therefore, the embodiments should be considered illustrative and non-limiting in all respects, and the scope of the invention is defined by the appended claims rather than the foregoing description. Thus, all variations falling within the meaning and scope of equivalents of the claims are intended to be included within the scope of the invention. No reference numerals in the claims should be construed as limiting the scope of the claims.

[0055] Furthermore, it should be understood that although this specification describes embodiments, not every embodiment contains only one independent technical solution. This narrative style is merely for clarity. Those skilled in the art should consider the specification as a whole, and the technical solutions in each embodiment can be appropriately combined to form other embodiments that can be understood by those skilled in the art. The above content is only for illustrating the technical concept of the present invention and should not be construed as limiting the scope of protection of the present invention. Any modifications made based on the technical concept proposed in this invention shall fall within the scope of protection of the claims of this invention.

Claims

1. A portable dual-path optical field inspection device based on paper chips, characterized in that, The portable detection box body (1) includes a hollow interior, an image acquisition device (2), a colorimetric detection system, a fluorescence detection system, a paper chip fixing device, and a temperature and humidity control device. The top cover of the portable detection box body (1) has a hole for matching the image acquisition device (2). The colorimetric detection system, the fluorescence detection system, and the temperature and humidity control device are located inside the portable detection box body (1). The paper chip fixing device is detachably located at the bottom of the portable detection box body (1).

2. The portable dual-path optical field inspection device based on paper chips according to claim 1, characterized in that, The portable detection dark box body (1) is made by 3D printing. A sealing strip is provided between the top cover of the portable detection dark box body and the portable detection dark box body (1). A light-proof baffle is provided inside the portable detection dark box body (1).

3. The portable dual-path optical field inspection device based on paper chips according to claim 1, characterized in that, The image acquisition device (2) is a fixed portable camera. The shooting distance is the fixed height of the portable detection box body (1). After the portable camera acquires the image, the image data is processed, including grayscale conversion, threshold segmentation and color analysis, to obtain the quantitative analysis results of the test object.

4. A portable dual-path optical field inspection device based on a paper chip according to claim 3, characterized in that, The portable detection box body (1) has holes on its top cover as a placement area for the camera (8) of the image acquisition device (2). The shape of the placement area is adapted to the placement of cameras (8) of different shapes. A rubber gasket is set on the inner side of the placement area.

5. A portable dual-path optical field inspection device based on a paper chip according to claim 1, characterized in that, The colorimetric detection system includes an illumination source (3), which is located on the top, side or bottom of the portable detection box body (1). The illumination source (3) is an LED light source or an incandescent lamp.

6. A portable dual-path optical field inspection device based on a paper chip according to claim 5, characterized in that, The geometric center of the lighting source (3) coincides with the center of the paper chip placement area (6).

7. A portable dual-path optical field inspection device based on a paper chip according to claim 1, characterized in that, The fluorescence detection system includes a fluorescence excitation source (4), which is either a uniform fluorescence excitation source or a focused fluorescence excitation source.

8. A portable dual-path optical field inspection device based on a paper chip according to claim 7, characterized in that, When the fluorescent excitation source is uniform, the fluorescent excitation source (4) is located on the top of the portable detection box body (1) and also includes a filter (9), which is set in front of the camera (8) of the image acquisition device (2); When the light source is a focused fluorescence excitation source, the fluorescence excitation source (4) is located on the side of the portable detection box body (1). The light source outlet is placed at an angle of 20° to 90° to the bottom of the portable detection box body (1). It also includes two lenses (10) and a filter (9). The size of the filter (9) matches that of the lens (10). The filter (9) is fixed between the two lenses (10) by a snap-on filter holder. The filter holder can be pulled out and replaced.

9. A portable dual-path optical field inspection device based on a paper chip according to claim 1, characterized in that, The paper chip fixing device includes a paper chip placement area (6), the middle of which is a solid square to support the paper-based microfluidic chip (5), and a snap-fit ​​structure is provided around the paper chip placement area (6) to fix the paper-based microfluidic chip (5) on the paper chip placement area (6); The temperature and humidity control device is a temperature and humidity control box (7). The temperature and humidity control box (7) mainly contains desiccant, humidifier and temperature control equipment, and is used to control the temperature and humidity of the paper chip reaction on the paper chip placement area (6).

10. A portable dual-path optical on-site detection method based on paper chips, characterized in that, The portable dual-path optical field inspection device based on a paper chip, as described in any one of claims 1 to 9, is used as follows: Set the image acquisition device (2) on the top cover of the portable detection box body (1) and align it with the paper chip placement area (6); The paper-based microfluidic chip (5) is placed on the paper chip fixing device and fixed to the bottom of the portable detection box body (1); When the concentration of the analyte is high, the colorimetric detection system is turned on, and the image acquisition device (2) acquires the image of the colorimetric detection paper-based microfluidic chip (5). The image is then processed to obtain the quantitative analysis results. When the concentration of the analyte is low, the fluorescence detection system is turned on and the image acquisition device (2) acquires the image of the paper-based microfluidic chip (5) detected by fluorescence method. The image is then processed to obtain the quantitative analysis results.

Images