Integrated detection assembly and method for food trace elements and animal residues in combination with enzymatic reaction

Abstract

The invention relates to the technical field of food safety detection, in particular to a food trace element and animal residue integrated detection assembly and method combined with an enzymatic reaction, and the assembly comprises a sample storage module which pumps liquid through a micro pump; the enzymatic reaction module comprises a substrate and a pair of mutually independent reaction units, the substrate is communicated and connected with the sample storage module through a pipeline, and the substrate is also communicated and connected with the pair of reaction units; wherein the two reaction units comprise a first immobilization enzyme aiming at heavy metal ions, a first reaction system for developing an enzyme reaction substrate, a second immobilization enzyme aiming at veterinary drug residues and a second reaction system for developing the enzyme reaction substrate. The first reaction unit aiming at heavy metal ions and the second reaction unit aiming at veterinary drug residues are integrated on the liquid outlet side of the same microfluidic substrate, one-time sample adding and synchronous distribution of the liquid to be detected are achieved through the microfluidic channel network, high integration and synchronization of the detection process are achieved, and the detection efficiency is improved.

Description

Technical Field

[0001] This invention relates to the field of food safety testing technology, specifically to an integrated detection component and method for trace elements and veterinary drug residues in food that combines enzymatic reactions. Background Technology

[0002] The field of food safety testing has increasingly urgent needs for rapid and simultaneous screening of trace harmful substances. Current technologies for detecting heavy metals and veterinary drug residues largely rely on large instruments such as atomic absorption spectrometry and liquid chromatography-mass spectrometry. While these methods offer high precision, they are complex, time-consuming, and costly, and typically require step-by-step execution, making them unsuitable for meeting the regulatory and production self-inspection needs for rapid, integrated on-site screening. Patent application CN202422755135.0 discloses an enzymatic hydrolysis device for fruit flavorings, comprising a reaction tank, a feed liquid storage tank, a standard alkali solution storage tank, a standard acid solution storage tank, and an enzyme solution storage tank. By optimizing the stirring structure and control method, the hydrolysis efficiency and mixing uniformity are improved. Furthermore, by employing a precise temperature control system and a multi-layer temperature sensor layout, accurate control of the reaction temperature is achieved, improving product quality stability.

[0003] While some enzyme-catalyzed reaction detection methods exist in the current technology, their applications are mostly limited to single-category target substances, and the detection devices often have low integration and limited automation. Therefore, there is a lack of an integrated rapid detection device that can highly integrate multiple enzyme-catalyzed reaction systems for different categories of hazardous substances and achieve automated sample addition, reaction, image acquisition, and intelligent analysis. Summary of the Invention

[0004] In order to overcome the deficiencies in the prior art, the present invention aims to provide an integrated detection component and method for trace elements in food and veterinary drug residues that combines enzymatic reactions, so as to solve the problems mentioned in the background art.

[0005] To achieve the above objectives, on the one hand, the present invention provides an integrated detection component for trace elements in food and veterinary drug residues that combines enzymatic reactions, including a sample storage module for storing the prepared test solution and pumping the solution using a micro pump; An enzyme-catalyzed reaction module includes a substrate and a pair of independent reaction units. The substrate is connected to a sample storage module via a pipe, and the substrate is also connected to the pair of reaction units. When one of the reaction units is a first type of reaction unit, it includes a first immobilizing enzyme targeting heavy metal ions and a first reaction system that develops color in the enzyme reaction substrate. When the other reaction unit is a second type of reaction unit, it includes a second immobilizing enzyme targeting veterinary drug residues and a second reaction system that develops color in the enzyme reaction substrate. The signal acquisition module uses an image acquisition device to synchronously acquire the signal changes generated by the enzyme-catalyzed reaction in each of the reaction units; The intelligent analysis module processes the collected signals through a computer and outputs the detection results of each target object based on the pre-stored data.

[0006] As a further improvement to this technical solution, the first solidifying enzyme is selected from at least one of urease, horseradish peroxidase, and alkaline phosphatase, and the heavy metal ions include at least one of lead (Pb), mercury (Hg), cadmium (Cd), and arsenic (As); the second solidifying enzyme is selected from at least one of β-lactamase, glucose oxidase, cholinesterase, acetylcholinesterase, and cytochrome P450 enzyme, and the veterinary drug residues include at least one of antibiotics, hormones, and β-receptor agonists.

[0007] As a further improvement to this technical solution, when the detectable signal is a color change, the first reaction system and the second reaction system contain substances that convert the corresponding enzyme reaction into a color signal; For detections based on the principle of enzyme inhibition, the substance includes pH indicators or peroxidase chromogenic substrates; For detections based on competitive inhibition or direct enzymatic hydrolysis, the substance includes a specific chromogenic substrate or a coupled chromogenic reagent.

[0008] As a further improvement to this technical solution, the substrate is a microfluidic chip and includes several S-shaped microfluidic channels. The reaction unit is a reaction chamber containing several independent cavities. A liquid passage is provided between every two rows of cavities inside the reaction chamber to connect the microfluidic channels and introduce the test liquid into the cavities for reaction with the solidified enzyme and the reaction system to develop color.

[0009] As a further improvement to this technical solution, the top surface of the reaction chamber is open and snapped with a cover, and the bottom surface of the cover is provided with several sealing platforms protruding side by side, and the sealing platforms are adapted to and snapped with the liquid passage.

[0010] As a further improvement to this technical solution, the intelligent analysis module is configured to: identify and extract color information within several cavities of the reaction chamber in the image obtained by the image acquisition device, convert the color information into signal change values, and then compare and analyze them with pre-stored data; the intelligent analysis module has a built-in database of standard curves for enzymatic reactions with trace elements and animal residues.

[0011] As a further improvement to this technical solution, the top surface of the substrate is provided with several liquid inlets, which are connected to several microfluidic channel inlets, and the front side of the substrate is provided with several liquid outlets, which are connected to several microfluidic channel outlets.

[0012] As a further improvement to this technical solution, one end face of the reaction chamber is provided with a liquid inlet that is connected to several liquid channels, and the side wall of the liquid channel is provided with a liquid distribution port that is connected to a cavity adjacent to the reaction chamber.

[0013] As a further improvement to this technical solution, the enzyme-catalyzed reaction module also includes a base frame that is adapted and snapped onto the substrate and several reaction units. Several reaction units are arranged side by side on the liquid outlet side of the substrate. The inner liner rod of the base frame located on the liquid outlet side of the substrate has several channels through it to connect the liquid outlet and the liquid inlet.

[0014] On the other hand, the present invention provides an integrated detection method for trace elements and veterinary drug residues in food that combines enzymatic reactions. Using the aforementioned integrated detection component for trace elements and veterinary drug residues in food that combines enzymatic reactions, the method includes the following steps: S1. Pre-process the food sample to be tested to obtain the test liquid, and pour it into the sample storage module; S2. Start the micro-pump on the sample storage module to inject the test solution into the substrate, then flow into all reaction units of the enzyme reaction module, and incubate at 25°C to 40°C for 5 to 20 minutes. S3. Then, the signal acquisition module is activated to synchronously capture the images of the enzyme-catalyzed reaction and colorimetric reaction that occur in each reaction unit, and the signal change values ​​before and after incubation or during incubation. S4. The intelligent analysis module receives the signal change value, compares and analyzes it with the pre-stored threshold or standard curve, and finally outputs whether there is an excessive amount of one or more trace elements and veterinary drug residues in the sample.

[0015] Compared with the prior art, the beneficial effects of the present invention are as follows: 1. This integrated detection component and method for trace elements in food and veterinary drug residues, which combines enzymatic reactions, integrates a first-type reaction unit for heavy metal ions and a second-type reaction unit for veterinary drug residues on the same microfluidic substrate outlet side. It also utilizes a microfluidic channel network to achieve one-time sample addition and synchronous distribution of the test solution, thus achieving a high degree of integration and synchronization of the detection process and improving detection efficiency.

[0016] 2. This integrated detection component and method for trace elements and veterinary drug residues in food, which combines enzymatic reactions, uses an image acquisition device as a signal acquisition module and is equipped with an intelligent analysis module to execute a complete algorithm process from image preprocessing, digital extraction of color information to comparison and analysis with a standard curve database. This completes the intelligent judgment of intuitive color changes into accurate concentration or qualitative results, thus achieving the effect of automated output of detection results.

[0017] 3. This integrated detection component and method for trace elements in food and veterinary drug residues, which combines enzymatic reactions, is designed with a reaction chamber structure containing independent cavities. Different immobilized enzymes and corresponding reaction systems are pre-placed in each cavity in a freeze-dried form. With the precise design of the cap and liquid passage, the physical isolation and stable preservation of the multi-enzyme reaction system are achieved, thereby preventing cross-interference and enabling simultaneous classification and detection. Attached Figure Description

[0018] The accompanying drawings described herein are for illustrative purposes only and are not intended to limit the scope of the invention in any way. Furthermore, the shapes and proportions of the components in the drawings are merely illustrative to aid in understanding the invention and do not specifically limit the shapes and proportions of the components. Those skilled in the art, guided by the teachings of this invention, will select various possible shapes and proportions to implement the invention according to specific circumstances.

[0019] Figure 1 This is one of the overall structural schematic diagrams of the present invention; Figure 2 This is the second schematic diagram of the overall structure of the present invention; Figure 3 This is a schematic diagram of the assembly structure of the enzyme-catalyzed reaction module of the present invention; Figure 4 This is a diagram showing the substrate of the present invention. Figure 5 This is a split diagram of the reaction unit of the present invention; Figure 6 For the present invention Figure 5 A schematic diagram of the structure at point A; Figure 7 This is one of the flowcharts of the present invention; Figure 8 This is the second flowchart of the present invention; The meanings of the labels in the diagram are as follows: 100. Sample storage module; 200. Enzyme-catalyzed reaction module; 210. Substrate; 211. Inlet; 212. Outlet; 220. Reaction unit; 221. Reaction chamber; 222. Liquid passage; 223. Dispensing port; 224. Liquid inlet; 225. Cap; 226. Sealing platform; 230. Substrate frame; 231. Channel opening; 300. Signal acquisition module; 400. Intelligent Analysis Module. Detailed Implementation

[0020] The details of the present invention can be more clearly understood by referring to the accompanying drawings and the description of specific embodiments. However, the specific embodiments of the present invention described herein are for illustrative purposes only and should not be construed as limiting the invention in any way. Under the teachings of this invention, those skilled in the art will conceive of any possible variations of the invention, all of which should be considered within the scope of the invention. The terms "installation" and "connection" should be interpreted broadly, referring to direct connection as well as indirect connection through an intermediate medium.

[0021] The terms "central axis," "vertical," "horizontal," "front," "rear," "upper," "lower," "left," "right," "top," "bottom," "inner," and "outer" used herein to indicate orientation or positional relationships are based on the orientation or positional relationships shown in the accompanying drawings and are used only for the convenience of describing the invention and simplifying the description, and are not intended to indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of the invention. Furthermore, in the description of the invention, "a number" means two or more, unless otherwise explicitly specified.

[0022] Please see Figures 1-3 As shown, the present invention provides an integrated detection component for trace elements in food and veterinary drug residues that combines enzymatic reaction, including a sample storage module 100, an enzymatic reaction module 200, a signal acquisition module 300, and an intelligent analysis module 400 installed inside the chassis. The sample storage module 100 and the signal acquisition module 300 are both suspended between the inner walls of the chassis by brackets, and the enzymatic reaction module 200 is embedded in the middle of the chassis platform and located below the signal acquisition module 300. The sample storage module 100 is used to store the prepared test solution and pump the solution using a micro pump; The signal acquisition module 300 uses image acquisition equipment, such as an industrial camera, to synchronously acquire the signal changes generated by the enzyme-catalyzed reaction in each reaction unit; The intelligent analysis module 400 is installed outside the chassis, which facilitates the operation and control of the computer to process the collected signals and output the detection results of each target object based on the pre-stored data.

[0023] This module operates as an automated image processing and data analysis workflow: Image preprocessing and recognition: The algorithm first identifies the precise location (ROI, region of interest) of each reactive unit in the image.

[0024] The color intensity of each unit region is digitally extracted, typically by converting the color (such as blue) into a grayscale value or a specific RGB channel intensity value (ΔRGB). This value represents the "signal change value".

[0025] Data comparison and analysis: The signal change value of each extracted unit is compared with a pre-stored standard curve database. This database stores the correspondence curves between different concentrations of the target substance and the signal value (i.e., color intensity).

[0026] Calling the correction algorithm: The algorithm will consider and subtract the matrix interference background signal caused by the sample's own color, turbidity, etc., to ensure the accuracy of the results.

[0027] Results generation and output: By comparing and calculating, the module determines whether each target substance exists and its concentration (quantitative) or is "negative / positive" (qualitative).

[0028] Finally, the test results of all items are summarized to generate a clear, integrated report, which is displayed on the screen or transmitted via an interface.

[0029] Specifically, such as Figures 4-8 As shown, the enzyme-catalyzed reaction module 200 includes a substrate 210 and a pair of independent reaction units 220. The substrate 210 is connected to the sample storage module 100 via a pipe. The substrate 210 is also connected to the pair of reaction units 220. The substrate 210 is used to guide the test solution to the reaction unit 220. When one of the reaction units 220 is a first type of reaction unit, it contains a first immobilized enzyme targeting heavy metal ions and a first reaction system that develops the color of the enzyme reaction substrate. When the other reaction unit 220 is a second type of reaction unit, it contains a second immobilized enzyme targeting veterinary drug residues and a second reaction system that develops the color of the enzyme reaction substrate.

[0030] Specifically, the first immobilized enzyme is selected from at least one of urease, horseradish peroxidase, and alkaline phosphatase, and the heavy metal ions include at least one of lead (Pb), mercury (Hg), cadmium (Cd), and arsenic (As); the immobilized urease is used to detect Hg. 2+ Pb 2+ Horseradish peroxidase is used to detect Cd. 2+ Alkaline phosphatase is used to detect As 3+ The corresponding reaction unit 220 chamber is pre-loaded with urea + phenol red indicator, hydrogen peroxide + HRP chromogenic substrate (TMB), and p-nitrophenyl phosphate.

[0031] The second immobilized enzyme is selected from at least one of β-lactamase, glucose oxidase, cholinesterase, acetylcholinesterase, and cytochrome P450 enzyme. Veterinary drug residues include at least one of antibiotics, hormones, and β-receptor agonists. Immobilized β-lactamase is used to detect penicillins, glucose oxidase to detect competitive inhibitors of sulfonamides, cholinesterase to detect organophosphates, and cytochrome P450 enzyme to detect specific hormones (such as certain steroid hormones). The corresponding chamber is pre-loaded with the appropriate chromogenic substrate or a chromogenic reaction system coupled with the enzyme, and a specific fluorescent substrate.

[0032] It is worth noting that when the detectable signal is a color change, both the first and second reaction systems contain substances that convert the corresponding enzymatic reaction into a color signal. I. For detection based on the principle of enzyme inhibition, the substance includes a pH indicator or a peroxidase chromogenic substrate; that is, the first reaction system is for trace heavy metal ions; Core principle: Heavy metal ions inhibit the activity of specific enzymes, leading to a decrease in their ability to catalyze colorimetric reactions, thereby causing changes in the rate of color formation or the final depth of color.

[0033] Example of system composition: For lead (Pb) 2+） Mercury (Hg) 2+） The system is based on urease inhibition; Enzyme: Urease; Enzyme substrate: urea; Signal transducers: pH indicators (such as phenol red and bromothymol blue).

[0034] Working principle: Urease normally catalyzes the hydrolysis of urea to produce ammonia and carbon dioxide, causing a local increase in pH value, which in turn changes the color of the pH indicator (e.g., phenol red changes from yellow to red). When Pb 2+ or Hg 2+ In its presence, urease activity is inhibited, pH elevation is slowed or stopped, resulting in reduced or no color change. The camera quantifies the degree of inhibition by capturing changes in red intensity or color ratio (red / green).

[0035] For cadmium (Cd) 2+） The system is based on horseradish peroxidase inhibition; Immobilizing enzyme: Horseradish peroxidase; Enzyme substrate: Hydrogen peroxide (H2O) 2） ; Signal transduction substances: chromogenic substrates, such as 3,3',5,5'-tetramethylbenzidine, TMB; or 2,2'-azido-bis(3-ethylbenzothiazoline-6-sulfonic acid), ABTS.

[0036] Working principle: HRP catalyzes the oxidation of TMB by H2O2, producing a blue product (or turning yellow after acid termination). Cd 2+ It can inhibit HRP activity, resulting in a slower blue color generation rate or a lighter final color. The camera detects this by analyzing the intensity of the blue channel or the overall color saturation.

[0037] II. For detections based on competitive inhibition or direct enzymatic hydrolysis, the substance includes a specific chromogenic substrate or a coupled chromogenic reagent. That is, the second reaction system targets veterinary drug residues; Core Principle A (Competitive Inhibition): Veterinary drugs compete with the normal substrate of enzymes for binding sites, inhibiting the formation of chromogenic products.

[0038] Core Principle B (Direct Enzymatic Reaction): Some veterinary drugs can serve as substrates for specific enzymes and be degraded into colored products.

[0039] Example of system composition: A system for β-lactam antibiotics (such as penicillin) based on β-lactamase hydrolysis; Immobilizing enzyme: β-lactamase; Enzyme substrate: A specific chromogenic cephalosporin (such as cefuroxime). The substrate itself is yellow, but turns red after being hydrolyzed by β-lactamase.

[0040] Working principle: If the sample does not contain penicillin, the β-lactamase is entirely used to hydrolyze the chromogenic substrate, producing a strong yellow to red color change. If the sample contains penicillin, it competes with the chromogenic substrate for enzyme binding sites, inhibiting the formation of the red product, resulting in a yellowish color. The camera quantifies the penicillin concentration by measuring the intensity ratio of the red to yellow channels.

[0041] III. Systems targeting organophosphorus and carbamate pesticides / veterinary drugs (based on cholinesterase inhibition); Immobilizing enzyme: acetylcholinesterase; Enzyme substrate: acetylthiocholine; Signal transducers: dual-color reagents, such as 5,5'-dithiobis(2-nitrobenzoic acid), DTNB.

[0042] Working principle: The enzyme normally catalyzes the hydrolysis of the substrate to produce thiocholine, which reacts with DTNB to form a yellow product (5-thio-2-nitrobenzoic acid, TNB). The target veterinary drug inhibits enzyme activity, reducing the formation of the yellow product. The intensity of the yellow color is detected by a camera.

[0043] IV. A system targeting sulfonamide veterinary drugs, based on competitive inhibition of glucose oxidase; Immobilizing enzyme: glucose oxidase; Enzyme substrate: glucose; Signal transduction substance: Coupled peroxidase colorimetric system (i.e., HRP + H2O2 + TMB). Gox catalyzes the oxidation of glucose to produce H2O2, and H2O2 oxidizes TMB under the catalysis of HRP, turning it blue.

[0044] Working principle: Certain sulfonamide drugs are competitive inhibitors of Gox. Their presence reduces the formation of H2O2, thereby weakening the subsequent blue reaction. The camera detects the intensity of the blue color.

[0045] In actual products, these reagents are typically pre-fixed in the cavities of each reaction unit in the form of lyophilized powder or pre-coated dry film to ensure stability and immediate use. When the test solution is added, the reagents dissolve and the reaction begins.

[0046] Specifically, the substrate 210 is a microfluidic chip, which is processed by photolithography or injection molding and contains several S-shaped microfluidic channels. In the micron-level channels, the fluid behavior is controllable, and the sample has more sufficient contact with the pre-installed solidified enzyme and reaction reagents in the chip, resulting in a faster reaction speed. The fluid is driven by capillary force, pump or centrifugal force, which reduces manual operation steps and reduces human error. The top surface of the substrate 210 is provided with several liquid inlets 211, which are connected to several microfluidic channel inlets. The front side of the substrate 210 is provided with several liquid outlets 212, which are connected to several microfluidic channel outlets. One end face of the reaction chamber 221 is provided with a liquid inlet 224 connected to several liquid channels 222. The side wall of the liquid channel 222 is provided with a liquid distribution port 223 connected to the cavity adjacent to the reaction chamber 221.

[0047] Specifically, the reaction unit 220 is a reaction chamber box 221 containing several independent cavities, made of transparent plastic to facilitate taking pictures and acquiring images; a liquid passage 222 is provided between each two rows of several cavities inside the reaction chamber box 221, which is used to connect the microfluidic channel to introduce the test liquid into several cavities, and react with the solidified enzyme and the reaction system to develop color.

[0048] The top surface of the reaction chamber 221 is open and is fitted with a cover 225. The bottom surface of the cover 225 has several sealing platforms 226 protruding side by side. The sealing platforms 226 are fitted and engaged with the liquid passage 222 to seal each reaction chamber 221 so that each chamber can react.

[0049] Furthermore, the intelligent analysis module is configured to: identify and extract color information within several cavities of the reaction chamber 221 in the image acquired by the image acquisition device, convert the color information into signal change values, and then compare and analyze them with pre-stored data; the intelligent analysis module has a built-in database of standard curves for enzymatic reactions with trace elements and animal residues.

[0050] In addition, the enzyme-catalyzed reaction module 200 also includes a base frame 230 that is adapted and snapped onto the substrate 210 and several reaction units 220. The base frame 230 is fixedly connected to the chassis platform. Several reaction units 220 are arranged side by side on the liquid outlet side of the substrate 210. Several channel openings 231 are opened through the inner liner rod of the base frame 230 located on the liquid outlet side of the substrate 210 for connecting the liquid outlet 212 and the liquid inlet 224.

[0051] The present invention provides an integrated detection method for trace elements and veterinary drug residues in food that combines enzymatic reactions. Using the aforementioned integrated detection component for trace elements and veterinary drug residues in food that combines enzymatic reactions, the method includes the following steps: S1. Pre-process the food sample to be tested to obtain the test liquid, and pour it into the sample storage module 100; S2. Start the micro-pump on the sample storage module 100 to inject the test solution into the substrate 210, and then flow into all reaction units 220 of the enzyme reaction module 200, and incubate at 25°C to 40°C for 5 to 20 minutes; the temperature is controlled by installing a heater and a temperature sensor under the platform of the chassis. S3. Then, the signal acquisition module 300 is activated to synchronously capture the images of the enzyme-catalyzed reaction and colorimetric reaction that occur in each reaction unit 220, and the signal change values ​​before and after incubation or during incubation. S4. The intelligent analysis module 400 receives the signal change value, compares and analyzes it with the pre-stored threshold or standard curve, and finally outputs whether there is an excessive amount of one or more trace elements and veterinary drug residues in the sample.

[0052] Example: Lead ions (Pb) in milk 2+ Simultaneous detection of ) and penicillin G 1. Equipment preparation: A detection assembly with two independent reaction units 220 was prepared. One reaction unit 220 had three cavities pre-filled with: urease + urea phenol red lyophilized bulbs, horseradish peroxidase + hydrogen peroxide (TMB) lyophilized bulbs, and alkaline phosphatase + p-nitrophenyl phosphate lyophilized bulbs, respectively. The other reaction unit 220 had three cavities pre-filled with: β-lactamase + cefotaxime lyophilized bulbs, glucose oxidase + glucose / HRP / TMB coupled system lyophilized bulbs, and cholinesterase + acetylthiocholine / DTNB lyophilized bulbs, respectively. The reaction chambers were then inserted into the substrate frame and the tubing was connected.

[0053] 2. Sample pretreatment: Take two 2 mL samples of commercially available milk, one as a blank control and the other with lead standard solution (final concentration 20 ppb) and penicillin G standard solution (final concentration 15 ppb). Add 4 mL of special extraction buffer (pH 7.4, containing EDTA and stabilizer) to each sample, vortex for 2 minutes, centrifuge at 8000 rpm for 5 minutes, and use the supernatant as the test solution.

[0054] 3. Testing process: The blank control solution was poured into the injection cell of the sample storage module 100. The micropump was started, pumping the liquid into the microfluidic substrate 210 at a flow rate of 10 μL / s. After being distributed through the S-shaped microfluidic channel, the liquid simultaneously entered the cavities of the two reaction units 220. The entire device was incubated at a constant temperature of 35°C for 10 minutes. After incubation, the industrial camera of the signal acquisition module 300 automatically captured high-resolution color images of the two reaction units 220.

[0055] 4. Intelligent Analysis: The intelligent analysis module 400's software automatically identifies the ROI of each cavity in the image. For the urease-phenol red system, it analyzes the average intensity value of the red channel; for the β-lactamase-cefotaxime system, it calculates the intensity ratio of the red to green channels. The obtained signal change values ​​are then compared with a pre-stored standard curve database.

[0056] 5. Output Results: The analysis module displays the test report on the screen: Blank sample: Pb 2+ Not detected (<5 ppb); Penicillin G: Not detected (<2 ppb).

[0057] Spiked sample: Pb 2+ Positive for: Penicillin G (18.5 ppb); Positive for: Penicillin G (14.1 ppb).

[0058] It should be noted that the above embodiments are only for illustrating the technical concept and features of the present invention, and are intended to enable those skilled in the art to understand the content of the present invention and implement it accordingly. They should not be used to limit the scope of protection of the present invention. All equivalent changes or modifications made in accordance with the spirit and essence of the present invention should be covered within the scope of protection of the present invention.

Claims

1. An integrated detection component for trace elements in food and veterinary drug residues combining enzymatic reactions, characterized in that: It includes a sample storage module for storing the prepared test solution and pumping the solution using a micro-pump; An enzyme-catalyzed reaction module includes a substrate and a pair of independent reaction units. The substrate is connected to a sample storage module via a pipe, and the substrate is also connected to the pair of reaction units. When one of the reaction units is a first type of reaction unit, it includes a first immobilizing enzyme targeting heavy metal ions and a first reaction system that develops color in the enzyme reaction substrate. When the other reaction unit is a second type of reaction unit, it includes a second immobilizing enzyme targeting veterinary drug residues and a second reaction system that develops color in the enzyme reaction substrate. The signal acquisition module uses an image acquisition device to synchronously acquire the signal changes generated by the enzyme-catalyzed reaction in each of the reaction units; The intelligent analysis module processes the collected signals through a computer and outputs the detection results of each target object based on the pre-stored data.

2. The integrated detection component for trace elements and veterinary drug residues in food combined with enzymatic reaction as described in claim 1, characterized in that: The first solidifying enzyme is selected from at least one of urease, horseradish peroxidase, and alkaline phosphatase, and the heavy metal ion includes at least one of lead, mercury, cadmium, and arsenic; the second solidifying enzyme is selected from at least one of β-lactamase, glucose oxidase, cholinesterase, acetylcholinesterase, and cytochrome P450 enzyme, and the veterinary drug residue includes at least one of antibiotics, hormones, and β-receptor agonists.

3. The integrated detection component for trace elements and veterinary drug residues in food combined with enzymatic reaction as described in claim 2, characterized in that: When the detectable signal is a color change, the first reaction system and the second reaction system contain substances that convert the corresponding enzyme reaction into a color signal; For detections based on the principle of enzyme inhibition, the substance includes pH indicators or peroxidase chromogenic substrates; For detections based on competitive inhibition or direct enzymatic hydrolysis, the substance includes a specific chromogenic substrate or a coupled chromogenic reagent.

4. The integrated detection component for trace elements and veterinary drug residues in food combined with enzymatic reaction as described in claim 3, characterized in that: The substrate is a microfluidic chip and contains several S-shaped microfluidic channels. The reaction unit is a reaction chamber containing several independent cavities. A liquid passage is provided between every two rows of cavities inside the reaction chamber to connect the microfluidic channels and introduce the test liquid into the cavities for reaction with the solidified enzyme and the reaction system to develop color.

5. The integrated detection component for trace elements and veterinary drug residues in food combined with enzymatic reaction as described in claim 4, characterized in that: The top surface of the reaction chamber is open and fitted with a cap. The bottom surface of the cap has several sealing platforms protruding side by side, and the sealing platforms are fitted and engaged with the liquid passage.

6. The integrated detection component for trace elements and veterinary drug residues in food combined with enzymatic reaction as described in claim 5, characterized in that: The intelligent analysis module is configured to: identify and extract color information from several cavities of the reaction chamber in the image acquired by the image acquisition device, convert the color information into signal change values, and then compare and analyze them with pre-stored data; the intelligent analysis module has a built-in database of standard curves for enzymatic reactions with trace elements and animal residues.

7. The integrated detection component for trace elements and veterinary drug residues in food combined with enzymatic reaction as described in claim 6, characterized in that: The top surface of the substrate has several liquid inlets, which are connected to several microfluidic channel inlets. The front side of the substrate has several liquid outlets, which are connected to several microfluidic channel outlets.

8. The integrated detection component for trace elements and veterinary drug residues in food combined with enzymatic reaction as described in claim 7, characterized in that: One end face of the reaction chamber is provided with a liquid inlet that is connected to several liquid channels, and the side wall of the liquid channel is provided with a liquid distribution port that is connected to a cavity adjacent to the reaction chamber.

9. The integrated detection component for trace elements and veterinary drug residues in food combined with enzymatic reaction as described in claim 8, characterized in that: The enzyme-catalyzed reaction module also includes a base frame that is adapted to and snaps onto the substrate and several reaction units. Several reaction units are arranged side by side on the liquid outlet side of the substrate. The inner liner rod of the base frame located on the liquid outlet side of the substrate has several channels through it to connect the liquid outlet and the liquid inlet.

10. A method for integrated detection of trace elements and veterinary drug residues in food using an enzymatic reaction, comprising the integrated detection component for trace elements and veterinary drug residues in food using an enzymatic reaction as described in claim 9, characterized in that, Includes the following steps: S1. Pre-process the food sample to be tested to obtain the test liquid, and pour it into the sample storage module; S2. Start the micro-pump on the sample storage module to inject the test solution into the substrate, then flow into all reaction units of the enzyme reaction module, and incubate at 25°C to 40°C for 5 to 20 minutes. S3. Then, the signal acquisition module is activated to synchronously capture the images of the enzyme-catalyzed reaction and colorimetric reaction that occur in each reaction unit, and the signal change values ​​before and after incubation or during incubation. S4. The intelligent analysis module receives the signal change value, compares and analyzes it with the pre-stored threshold or standard curve, and finally outputs whether there is an excessive amount of one or more trace elements and veterinary drug residues in the sample.

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