A detector for bacterial endotoxin test

Abstract

This utility model relates to a detector for bacterial endotoxin testing, belonging to the field of biomedical detection technology. It includes a device base, a microplate stage, a camera assembly, a motor drive assembly, and a temperature control module. The device base is equipped with a bracket and guide rail assembly for supporting and mounting the various functional components. A microplate tray is fixed on the microplate stage, and a microplate is fixed to the microplate tray via a microplate fixing mechanism. The microplate tray has positioning grooves that match the shape of the microplate. The camera assembly is fixed to the bracket via a camera fixing mechanism and is located on the same vertical axis as the microplate tray. The motor drive assembly is mounted on the device base or bracket and connected to a transmission mechanism via a coupling, used to drive the microplate stage to move along the guide rail assembly. This utility model has a high degree of automation, significantly improving the efficiency and accuracy of bacterial endotoxin detection, and is suitable for rapid detection needs in medical, pharmaceutical production, and other scenarios.

Description

Technical Field

[0001] This utility model relates to the field of biomedical detection technology, and in particular to a detector for bacterial endotoxin testing. Background Technology

[0002] Bacterial endotoxins are thermostable toxins released from the cell walls of Gram-negative bacteria during cell lysis or death. They possess extremely high pyrogenicity and toxicity. Even trace amounts of endotoxins entering the human bloodstream can trigger serious consequences such as fever, inflammatory responses, and even shock. Therefore, the detection of bacterial endotoxins has become a crucial aspect of product quality control in the pharmaceutical, medical device, and biological product industries.

[0003] Currently, commonly used detection methods mainly include gel permeation, turbidimetry, and colorimetry. While these methods are widely used, they largely rely on manual operation and judgment, such as visually observing whether the reaction has gelled or changed color to determine whether it is positive or negative. This approach is highly subjective, has poor repeatability, and is inefficient in high-throughput detection scenarios, failing to meet the demands of modern pharmaceutical production processes for rapid, accurate, and standardized testing. With the development of automation and image processing technologies, introducing camera recognition and image analysis algorithms into the bacterial endotoxin detection process has become an important means to improve detection efficiency and accuracy. By acquiring images of the reaction plate using a high-definition camera and combining this with algorithms to automatically determine changes in color or turbidity within the wells, not only can manual interpretation be replaced, but batch data analysis and automatic recording can also be achieved, significantly improving experimental efficiency and traceability.

[0004] However, the market currently lacks bacterial endotoxin detection equipment that integrates multiple functions such as constant temperature control, image recognition, and automatic data processing. Existing image recognition devices are either complex in structure, expensive, or still rely on manual intervention, failing to achieve truly automated detection. Therefore, developing a compact, accurate, and easy-to-operate bacterial endotoxin culture monitoring and detection instrument is of significant technical importance and has broad market application prospects. Utility Model Content

[0005] To overcome the technical defects of the existing technology, this utility model provides a detector for bacterial endotoxin testing, which has the technical effects of high automation, high detection efficiency and high accuracy.

[0006] The technical solution adopted by this utility model is as follows: it includes a device base, a perforated plate platform, a camera assembly, a motor drive assembly, and a constant temperature control module. The device base is provided with a bracket and guide rail assembly for supporting and installing various functional components. A perforated plate tray is fixed on the perforated plate platform. The micro-perforated plate is fixed on the perforated plate tray by a perforated plate fixing mechanism. The perforated plate tray is provided with a positioning groove that matches the shape of the micro-perforated plate. The camera assembly is fixed on the bracket by a camera fixing mechanism and is located on the same vertical axis as the perforated plate tray. The motor drive assembly is installed on the device base or the bracket and is connected to the transmission mechanism through a coupling. It is used to drive the perforated plate platform to move along the guide rail assembly, so that the perforated plate platform can move in the X / Y direction. Each detection hole in the micro-perforated plate moves sequentially to the bottom of the camera assembly for image acquisition. The constant temperature control module includes a heating element installed on the bracket, a temperature sensor installed on the device base, and a constant temperature control circuit to form a heating environment.

[0007] Preferably, the guide rail assembly is equipped with a position sensor located on the movement path of the perforated plate stage, which is used to detect the position of the perforated plate stage and cooperate with the motor drive assembly to achieve positioning control.

[0008] Preferably, a control circuit board is provided in the heat insulation chamber inside the base, and the control circuit board is electrically connected to the motor drive assembly, position sensor, light source module, camera assembly and constant temperature control module.

[0009] Preferably, a light source module mounting plate is fixed below the bracket, and a constant current driven LED light source module is mounted above the light source module mounting plate, with its illumination direction perpendicular to the plane of the perforated plate tray.

[0010] Preferably, the LED light source module adopts an LED array and a light distribution mask structure. The light source is powered by a constant current driving circuit, and the light distribution mask is located between the light source and the perforated plate tray to eliminate light spots.

[0011] Preferably, the heating element of the constant temperature control module is a ceramic heating element or a flexible heating film. The heating element is symmetrically installed on the support around the perforated plate tray and heats the perforated plate tray through radiation and convection.

[0012] Preferably, the camera assembly is an industrial CMOS camera, which is fixed by an adjustable focus bracket, and its optical axis coincides with the central axis of the perforated plate tray.

[0013] Preferably, the guide rail assembly consists of two parallel linear guide rails and a slider that cooperates with them. The slider is fixed to the bottom of the perforated plate stage by screws, so that the perforated plate stage can move in the direction of the guide rails.

[0014] Preferably, the motor drive assembly is a stepper motor fixed on the bracket. The output shaft of the stepper motor is connected to a ball screw through a flexible coupling. The ball screw is arranged parallel to one side of the guide rail assembly. The ball screw is fixed to both ends of the equipment base through bearing seats. The ball screw meshes with the nut seat on the slider. The rotation of the stepper motor drives the ball screw to rotate, realizing the linear movement of the slider and the hole plate platform fixed on the slider along the guide rail.

[0015] Preferably, the equipment base is made of steel or aluminum alloy, and the bottom surface of the equipment base is provided with shock-absorbing rubber pads.

[0016] The beneficial effects of this utility model are:

[0017] 1. This detector integrates modules such as constant temperature control, image acquisition, and intelligent judgment. It can be started with one button and automatically execute preset processes from the moment the orifice plate is placed into the device, which greatly reduces manual operation steps and lowers the technical threshold for operators. It accurately acquires images through a camera and uses image recognition algorithms to judge the color depth and change trend, thereby achieving objective and stable positive and negative determination and avoiding judgment deviations caused by differences in personnel experience, lighting environment, and other factors.

[0018] 2. Through the coordinated operation of the motor drive module and the position sensing module, the automatic displacement of the reaction plate can be realized, so that multiple wells are aligned with the camera for detection in sequence. There is no need to manually replace or adjust the position of the well plate during the entire detection process. It is suitable for batch monitoring of standard microplates such as 96-well plates, which greatly improves the detection throughput and work efficiency.

[0019] 3. A constant temperature control module ensures that each well is always within the set reaction temperature range, preventing temperature fluctuations from affecting the reaction rate or results. A constant current light source module provides a uniform illumination environment, offering consistent background conditions for image recognition and preventing distortion of detection results due to external light interference. Attached Figure Description

[0020] Figure 1 This is a system block diagram of the present invention;

[0021] Figure 2 This is a three-dimensional structural schematic diagram of the present invention;

[0022] Figure 3 This is a schematic diagram of the constant temperature control module structure of this utility model;

[0023] Figure 4 This is a schematic diagram of the motor drive and transmission structure of this utility model;

[0024] Figure 5 This is a schematic diagram of the constant current module structure of the light source of this utility model;

[0025] Figure 6 This is a schematic diagram of the overall structure of this utility model from the left side view.

[0026] Explanation of reference numerals in the attached figures: 1. Camera assembly; 2. Heating element; 3. Light source module mounting plate; 4. Perforated plate tray; 5. Perforated plate platform; 6. Motor drive assembly; 7. Camera fixing mechanism; 8. Position sensor; 9. Bracket; 10. Guide rail assembly; 11. Perforated plate fixing mechanism; 12. Equipment base; 13. LED light source module; 14. Temperature sensor. Detailed Implementation

[0027] The present invention will be further described below with reference to the accompanying drawings:

[0028] like Figures 1-6 As shown, this embodiment provides a detector for bacterial endotoxin testing, including a device base 12, a well plate stage 5, a camera assembly 1, a motor drive assembly 6, and a constant temperature control module.

[0029] The equipment base 12 is equipped with brackets 9 and guide rail assemblies 10 for supporting and installing various functional components. The equipment base 12 is integrally machined from steel or aluminum alloy, and the bottom surface is equipped with shock-absorbing rubber feet to reduce the impact of environmental vibration on the detection accuracy. Two vertical columns are fixed to the upper surface of the equipment base 12 with screws, and the upper ends of the columns are connected by crossbeams to form a stable frame structure.

[0030] A perforated plate tray 4 is fixed on the perforated plate stage 5. The micro-perforated plate is fixed on the perforated plate tray 4 by the perforated plate fixing mechanism 11. The perforated plate tray 4 is machined with positioning grooves that match the standard perforated plates with 96 or 48 holes, and limiting bosses are set around the positioning grooves to ensure the stability and repeatability of the micro-perforated plate during the testing process.

[0031] The camera assembly 1 is fixed to the bracket 9 via the camera fixing mechanism 7 and is located on the same vertical axis as the perforated plate tray 4. The camera assembly 1 periodically acquires images of the perforated plate. The system extracts, compares, and judges the color information of each perforation in the image, and judges the color change trend based on a set threshold, thereby automatically determining whether the detection result of each perforation is negative or positive. This module also has anomaly recognition, image enhancement, and data archiving functions, which can bind and store images and judgment results to meet traceability requirements. The bracket 9 has up / down, forward / backward, and left / right fine-tuning functions, so that the optical axis of the camera assembly 1 can be precisely aligned with the central axis of the perforated plate tray 4, thereby ensuring that the imaging area is consistent with the detection perforation. The camera assembly 1 and the LED light source module 13 are arranged coaxially to form a vertical optical path structure to reduce imaging distortion and shadow interference.

[0032] The motor drive assembly 6 is mounted on the equipment base 12 or bracket 9 and connected to the transmission mechanism via a coupling. It drives the perforated plate stage 5 to move along the guide rail assembly 10, allowing the stage 5 to move in the X / Y directions. Each detection hole within the microplate moves sequentially below the camera assembly 1 for image acquisition. The reaction plate or stage 5 is driven by a stepper motor or servo motor to achieve automatic positioning and sequential scanning of multiple holes. Combined with the position sensor 8, it ensures that the target hole is accurately aligned with the camera area each time an image is acquired, improving image recognition accuracy and detection efficiency, and supporting high-throughput continuous detection.

[0033] The constant temperature control module includes a heating element 2 mounted on the bracket 9, a temperature sensor 14 mounted on the equipment base 12, and a constant temperature control circuit, forming a heating environment to provide a constant and stable temperature environment (such as 37°C) for bacterial endotoxin reactions, ensuring that the reaction system is under optimal biochemical reaction conditions. The module is equipped with a temperature sensor 14 and a control chip, and uses a closed-loop PID control algorithm to adjust the power of the heating element in real time, so that the temperature difference is controlled within ±0.2°C, thereby improving the stability and consistency of the detection results.

[0034] Heating element 2 is either a flexible heating film or a ceramic heating plate. It is fixed to the bottom of the well plate tray 4 via a metal substrate with high thermal conductivity and is in close contact with the bottom surface of the well plate tray 4 to reduce heat loss and achieve efficient and uniform heat conduction. Temperature sensor 14 is attached to the heating element 2 near the center and connected to the control circuit board via a shielded wire. It can monitor the temperature in real time and feed it back to the main control system. The control circuit board is fixed in the heat-insulated chamber inside the equipment base 12. Heat sinks and evenly distributed ventilation holes are arranged around the module. Heat circulation is formed by natural convection or a micro fan to avoid local temperature differences and ensure that the temperature of the entire microplate area is uniform. This provides a stable and reliable culture environment for bacterial endotoxin reaction and effectively reduces the impact of temperature fluctuations on experimental results.

[0035] Preferably, the guide rail assembly 10 is provided with a position sensor 8 located on the movement path of the perforated plate stage 5, which is used to detect the position of the perforated plate stage 5 and cooperate with the motor drive assembly 6 to achieve positioning control. The position sensor 8 adopts any one of photoelectric sensor, Hall sensor or encoder, monitors the position status of the perforated plate or stage in real time, and feeds back the position information to the main control system to ensure that each detection hole is in a precise position when the image is acquired, prevents image offset or repeated acquisition, and ensures accurate recognition results.

[0036] As a technical optimization of this utility model, a control circuit board is provided in the heat insulation chamber inside the base 12. The control circuit board is electrically connected to the motor drive assembly 6, the position sensor 8, the LED light source module 13, the camera assembly 1, and the constant temperature control module.

[0037] As a technical optimization of this utility model, a light source module mounting plate 3 is fixed below the bracket 9. The light source module mounting plate 3 is made of metal sheet with an anodized surface, which can both fix the light source module and provide good heat dissipation performance. A constant current driven LED light source module 13 is mounted on the top of the light source module mounting plate 3, and its illumination direction is perpendicular to the plane of the perforated plate tray 4. Several mounting holes are evenly distributed on the lower surface of the light source module mounting plate 3 for fixing the constant current driven LED light source module 13. The illumination direction of the light source is perpendicular to the plane of the micro-perforated plate tray 4 to ensure that the light uniformly covers the detection area. The LED light source module 13 adopts an LED array and a light distribution mask structure. The light source is powered by a constant current driving circuit. The light distribution mask is located between the light source and the perforated plate tray 4 to eliminate light spots and provide stable and uniform illumination conditions for the image acquisition area. Using a constant current power supply to drive the LED light source module 13 effectively avoids image deviations caused by brightness fluctuations or power supply interference in traditional lighting. In conjunction with a diffuse reflector or light distribution mask, the image clarity and color reproduction capability are further improved, providing a stable foundation for subsequent image analysis.

[0038] As a technical optimization of this utility model, the heating element 2 of the constant temperature control module is a ceramic heating element or a flexible heating film. The heating element 2 is symmetrically installed on the support 9 around the perforated plate tray 4, and heats the perforated plate tray by radiation and convection.

[0039] As a technical optimization of this utility model, the camera assembly 1 is an industrial CMOS camera, fixed by an adjustable focus bracket. Its optical axis coincides with the central axis of the perforated plate tray 4. The camera assembly 1 has high resolution and high sensitivity imaging capabilities. It is connected to the image acquisition interface module via a high-speed USB 3.0 data cable. The acquisition interface module is fixed inside the device base 12 and communicates bidirectionally with the control circuit board to achieve high-speed image transmission and cache management. The image processing main control unit can be integrated on the main control board or an external computing module can be used. It performs noise reduction, illumination equalization, color analysis, edge detection, and feature extraction on the acquired image through a dedicated algorithm. It automatically judges the reaction status of each detection hole according to a preset threshold and stores or transmits the analysis results and the original image to the host computer, realizing the automation, standardization, and traceability of the entire detection process, greatly improving detection efficiency and data reliability. The image processing main control unit can be deployed on a local MCU or connected to an external computing unit (such as a Raspberry Pi, industrial PC, etc.) through a hub interface to realize real-time image processing and analysis. The image processing workflow includes: raw image acquisition, image preprocessing (denoising and correction), color recognition and comparison, and positive / negative color determination, among other algorithmic steps. The system can accurately identify the reaction result of each well in the microplate by setting a color threshold or using a machine learning model, and then convert the results into numerical or image information and upload it to a host computer system or LIMS platform.

[0040] As a technical optimization of this utility model, the guide rail assembly 10 consists of two parallel linear guide rails and a slider that cooperates with them. The slider is fixed to the bottom of the perforated plate platform 5 by screws, so that the perforated plate platform 5 can move in the direction of the guide rails.

[0041] As a technical optimization of this utility model, the motor drive assembly 6 is a stepper motor fixed on the bracket 12. The output shaft of the stepper motor is connected to the ball screw through an elastic coupling. The coupling can compensate for slight coaxiality deviation, reduce vibration and extend the service life of the transmission system. The ball screw is arranged parallel to one side of the guide rail assembly 10. The ball screw is fixed to both ends of the equipment base 12 through bearing seats. The ball screw meshes with the nut seat on the slider. The rotation of the stepper motor drives the ball screw to rotate, realizing the linear movement of the slider and the hole plate platform 5 fixed on the slider along the guide rail.

[0042] In another embodiment, the transmission method can also use a synchronous pulley and a synchronous belt, wherein the synchronous pulley is connected to the motor shaft through a coupling, and after the pulley is tensioned, it cooperates with the synchronous belt to drive the platform to run. This structure has advantages in terms of running speed and noise.

[0043] The foregoing has shown and described the basic principles, main features, and advantages of this invention. Those skilled in the art should understand that this invention is not limited to the above embodiments. The embodiments and descriptions in the specification are merely illustrative of the principles of this invention. Various changes and modifications may be made to this invention without departing from its spirit and scope. All such changes and modifications fall within the scope of this invention as defined by the appended claims and their equivalents.

Claims

1. A detector for bacterial endotoxin testing, characterized by, The application relates to a microplate imaging device, which comprises the following components: a device base (12) provided with a support (9) and a guide rail assembly (10) for supporting and mounting various functional components; a microplate carrier (5) provided with a microplate tray (4) fixedly arranged on the microplate carrier (5), a microplate being fixed on the microplate tray (4) through a microplate fixing mechanism (11), and the microplate tray (4) being provided with a positioning groove matched with the shape of the microplate; a camera assembly (1) fixed on the support (9) through a camera fixing mechanism (7) and located on the same vertical axis as the microplate tray (4); a motor driving assembly (6) installed on the device base (12) or the support (9) and connected with a transmission mechanism through a shaft coupling, used for driving the microplate carrier (5) to move along the guide rail assembly (10) so that the microplate carrier (5) can move in X / Y directions and the detection holes in the microplate move to the camera assembly (1) in sequence for image acquisition; a constant temperature control module comprising a heating element (2) installed on the support (9), a temperature sensor (14) installed on the device base (12) and a constant temperature control circuit, and forming a heating environment.

2. The tester for bacterial endotoxin testing according to claim 1, characterized in that, The guide rail assembly (10) is provided with a position sensor (8) located on the movement path of the microplate carrier (5), used for detecting the position of the microplate carrier (5) and cooperating with the motor driving assembly (6) to realize positioning control.

3. The tester for bacterial endotoxin testing according to claim 1, characterized in that, A control circuit board is arranged in a heat insulation chamber in the base (12), and the control circuit board is electrically connected with the motor driving assembly (6), the position sensor (8), a light source module (13), the camera assembly (1) and the constant temperature control module.

4. The tester for bacterial endotoxin testing according to claim 1, characterized in that, A light source module mounting plate (3) is fixed below the support (9), and a constant current driven LED light source module (13) is installed above the light source module mounting plate (3), and the irradiation direction of the LED light source module (13) is perpendicular to the plane of the microplate tray (4).

5. The tester for bacterial endotoxin testing according to claim 4, characterized in that, The LED light source module (13) adopts an LED array and a light homogenizing cover structure, the light source is powered by a constant current driving circuit, and the light homogenizing cover is located between the light source and the microplate tray (4) and used for eliminating light spots.

6. The tester for bacterial endotoxin testing according to claim 1, characterized in that, The heating element (2) of the constant temperature control module is a ceramic heating element or a flexible heating film, and the heating element (2) is symmetrically installed on the support (9) around the microplate tray (4) and heats the microplate tray through radiation and convection.

7. The tester for bacterial endotoxin testing according to claim 1, characterized in that, The camera assembly (1) is an industrial CMOS camera fixed through an adjustable focus support, and the optical axis of the camera assembly (1) coincides with the central axis of the microplate tray (4).

8. The tester for bacterial endotoxin testing according to claim 1, characterized in that, The guide rail assembly (10) comprises two parallel straight guide rails and sliders matched with the guide rails, and the sliders are fixed to the bottom of the microplate carrier (5) through screws, so that the microplate carrier (5) can move in the direction of the guide rails.

9. The tester for bacterial endotoxin testing according to claim 8, characterized in that, The motor driving assembly (6) is a stepping motor fixed on a support (9), an output shaft of the stepping motor is connected with a ball screw through an elastic coupling, the ball screw is arranged in parallel on one side of a guide rail assembly (10), the ball screw is fixed on both ends of an equipment base (12) through a bearing seat, the ball screw is engaged with a nut seat on a sliding block, the stepping motor rotates to drive the ball screw to rotate, and linear movement of the sliding block and a hole plate carrier (5) fixed on the sliding block along the guide rail is realized.

10. The tester for bacterial endotoxin testing according to claim 1, characterized in that, The equipment base (12) is made of steel or aluminum alloy, and the bottom surface of the equipment base (12) is provided with shockproof rubber foot pads.

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