Portable pesticide residue detection device

Abstract

The utility model relates to the technical field of agricultural residue detection, and specifically discloses a portable agricultural residue detection device for food, which comprises a detection plate, mounting plates fixed on both sides of the detection plate, two groups of reagent confirmation boxes mounted on the detection plate, two groups of matrix interference exclusion boxes mounted on the detection plate and two groups of experiment boxes mounted on the detection plate. The reagent confirmation boxes confirm the stability of reagents, the matrix interference exclusion boxes exclude the non-specific inhibition of the matrix of the agricultural products to be detected on the enzyme activity, and the experiment boxes react with the agricultural residues in the food to be detected. A comparison groove is formed on the detection plate, a plurality of partitions are mounted in the comparison groove, the partitions divide the comparison groove into a first comparison area in communication with the reagent confirmation boxes and a second comparison area in communication with the matrix interference exclusion boxes, and an inclined channel is arranged between the first comparison area, the second comparison area, the reagent confirmation boxes and the matrix interference exclusion boxes. The device solves the problem of insufficient reliability of detection results caused by the traditional instant screening method.

Description

Technical Field

[0001] This application relates to the field of pesticide residue detection technology, and specifically discloses a portable device for detecting pesticide residues in food. Background Technology

[0002] Food safety is a core issue related to public health, social stability, and industrial development. Pesticide residues, as one of the most significant safety risks in agricultural product production and processing, require rapid and accurate detection for source control, market supervision, and consumer protection. While traditional laboratory testing technologies can achieve precise qualitative and quantitative analysis in on-site settings such as farmers' markets, supermarkets, grassroots agricultural supervision, and agricultural product production areas, they suffer from drawbacks such as bulky equipment, complex operation, long testing cycles, and high costs, failing to meet the practical needs for immediate screening and rapid early warning. Enzyme inhibition, as one of the most widely used rapid pesticide residue detection technologies, is widely adapted to portable detection devices due to its advantages such as simple principle, convenient operation, fast detection speed, low cost, and no need for professional technicians. Its core detection logic is as follows: common pesticides such as organophosphates and carbamates specifically inhibit the activity of acetylcholinesterase. If a sample contains these pesticides, enzyme activity will be inhibited, thus hindering the subsequent reaction between the substrate and the chromogenic agent. By comparing the color intensity or absorbance of the reaction system, a preliminary judgment can be made as to whether the pesticide residue exceeds the standard. The characteristics of this technology make it naturally suitable for the development of portable devices, meeting the core requirement of rapid on-site screening. However, existing portable pesticide detection devices based on enzyme inhibition methods still have significant technical shortcomings in practical applications, seriously affecting the reliability and accuracy of detection results. The most prominent problems are a high false positive rate and a large detection error. Specifically, the causes of these shortcomings mainly include the following aspects: 1. Sample matrix interference: Some agricultural products contain active ingredients that may not specifically inhibit the activity of acetylcholinesterase, mimicking the inhibitory effect of pesticides and leading to false positive results. 2. Impact of reagent stability: Temperature and humidity fluctuations in portable testing scenarios, as well as batch differences and degradation of the reagents themselves, may lead to instability in the enzyme activity baseline value, thereby affecting the comparability of test results; 3. Differences in operation and reaction conditions: In on-site testing, factors such as operator errors in sample addition and inconsistent control of reaction time can further amplify detection deviations; 4. Single control group setup: Most existing portable devices only set up one blank control group and one sample detection group for comparison, which cannot effectively eliminate the influence of systematic factors such as matrix interference, reagent fluctuations, and operational errors. This results in a high degree of randomness and error in the results of a single comparison, and it is difficult to effectively control the false positive problem. The aforementioned problems directly lead to insufficient reliability of test results: on the one hand, false positive results may cause qualified agricultural products to be misjudged as products exceeding the standard, causing unnecessary economic losses to farmers and distributors; on the other hand, serious detection errors may mask the real risk of pesticide residue exceeding the standard, making it impossible to achieve effective safety warnings. In view of this, the present invention provides a portable pesticide residue detection device in food in order to solve the above problems. Utility Model Content

[0003] The purpose of this invention is to solve the problem of insufficient reliability of test results caused by traditional instant screening methods.

[0004] To achieve the above objectives, this utility model provides the following basic solution: A portable device for detecting pesticide residues in food includes a detection plate, mounting plates fixed to both sides of the detection plate, two sets of reagent confirmation boxes mounted on the detection plate, two sets of matrix interference exclusion boxes mounted on the detection plate, and two sets of experimental boxes mounted on the detection plate. The reagent confirmation chamber confirms the stability of the reagents, the matrix interference elimination chamber eliminates the non-specific inhibition of enzyme activity by the matrix of the agricultural product to be tested, and the experimental chamber reacts with pesticide residues in the food to be tested. The detection plate has a contrast groove, and several partitions are installed in the contrast groove. The partitions divide the contrast groove into a first contrast area that is connected to the reagent confirmation box and a second contrast area that is connected to the matrix interference exclusion box. Inclined channels are provided between the first contrast area and the reagent confirmation box and the matrix interference exclusion box.

[0005] Furthermore, the reagent confirmation box, matrix interference elimination box, and experimental box have the same structure, material, and shape. The reagent confirmation box, matrix interference elimination box, and experimental box include a box body, an end cap, a connecting hole at the bottom of the box body, and a plug that is detachably connected to the connecting hole. The box body and the end cap are threaded together.

[0006] Furthermore, a light-shielding base plate for reducing the impact of light is embedded at the bottom of the first comparison area.

[0007] Furthermore, the mounting plate and the detection plate are integrally formed, and the height of the upper surface of the detection plate is lower than the height of the upper surface of the mounting plate.

[0008] Furthermore, the detection plate has slots at both the upper and lower ends for handheld carrying, and the inside of the slots is rounded.

[0009] Furthermore, the reagent confirmation box is filled with a first detection reagent and a second detection reagent, respectively. The first detection reagent includes a buffer solution, an enzyme reagent, a substrate, and a chromogenic agent, and the second detection reagent includes an enzyme reagent, a substrate, and a chromogenic agent.

[0010] Furthermore, the enzyme reagent is acetylcholinesterase, the substrate is thioacetylcholine, the colorimetric reagent is dithiodinitrobenzoic acid, and the buffer solution is phosphate buffer.

[0011] Furthermore, a transparent cover plate is detachably connected to the comparison groove.

[0012] The principle and effect of this solution are as follows: Compared with existing technologies, the core of this device lies in reducing detection errors and solving the problem of insufficient reliability of detection results caused by traditional point screening methods. This is mainly achieved by using a reagent confirmation chamber to confirm the stability of reagents and buffer solutions, eliminating interference from enzymes, substrates, chromogenic agents, buffer solutions, temperature, and humidity on the detection results, and confirming the stability of the reagents. Secondly, a matrix interference elimination chamber is set up to eliminate the non-specific inhibition of enzyme activity by the matrix of the agricultural product being tested, thus solving the core problem of false positives caused by matrix interference.

[0013] The core innovation of this device lies in constructing a multi-group control system with "dual reagent confirmation and dual matrix interference elimination". The reagent confirmation box eliminates reagent instability and buffer interference, and the matrix interference elimination box eliminates non-specific inhibition of the sample matrix itself. This solves the key pain points of high false positive rate and large error in traditional devices and breaks through the design limitations of a single control group. Attached Figure Description

[0014] To more clearly illustrate the technical solutions in the embodiments of this application, the accompanying drawings used in the description of the embodiments will be briefly introduced below. Obviously, the accompanying drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0015] Figure 1 This paper shows a schematic diagram of the structure of a portable pesticide residue detection device in food according to an embodiment of this application; Figure 2 The diagram shows a front view of a portable food pesticide residue detection device according to an embodiment of this application. Detailed Implementation

[0016] To further illustrate the technical means and effects adopted by this utility model in order to achieve the intended utility model purpose, the following detailed description of the specific implementation methods, structure, features and effects of this utility model is provided in conjunction with the accompanying drawings and preferred embodiments.

[0017] The reference numerals in the accompanying drawings include: 1. Detection plate; 2. Mounting plate; 3. Experimental chamber; 4. End cap; 5. Matrix interference exclusion chamber; 7. Reagent confirmation chamber; 9. Inclined channel; 10. First comparison area; 12. Second comparison area; 13. Occlusion; 14. Slot; 15. Partition.

[0018] Implementation, for example Figure 1 , Figure 2 As shown: A portable pesticide residue detection device for food includes a detection plate 1, mounting plates 2 fixed to both sides of the detection plate 1, two sets of reagent confirmation boxes 7 mounted on the detection plate 1, two sets of matrix interference elimination boxes 5 mounted on the detection plate 1, and two sets of experimental boxes 3 mounted on the detection plate 1. Scale lines are added to the experimental chamber 3 and the matrix interference elimination chamber 5 to clarify the sample addition benchmark and reduce human error in sample addition. A sealing ring is added to the end cap 4 to avoid dust and liquid contamination during on-site testing.

[0019] Specifically: such as Figure 1 As shown, the detection plate 1 is in the center, and the mounting plate 2 is located on both sides of the detection plate 1. The mounting plate 2 is integrally formed with the detection plate 1, and the height of the upper surface of the detection plate 1 is lower than the height of the upper surface of the mounting plate 2, so that the detection plate 1 is in a low position, which facilitates the subsequent operation of the detection plate 1.

[0020] The detection plate 1 has slots 14 at both the upper and lower ends for hand-held carrying. The slots 14 have rounded corners inside, and the device can be carried through the slots 14.

[0021] The reagent confirmation box 7 confirms the stability of the reagents, the matrix interference elimination box 5 eliminates the non-specific inhibition of enzyme activity by the matrix of the agricultural product to be tested, and the experimental box 3 reacts with pesticide residues in the food to be tested. The detection plate 1 has a comparison slot, and a transparent cover is detachably connected to the comparison slot. The transparent cover prevents external dust from falling in during the reaction and forms a sealed environment to reduce the impact of temperature and humidity fluctuations on the reaction. Several partitions 15 are installed in the comparison slot, which divides the comparison slot into a first comparison area 10 connected to the reagent confirmation box 7 and a second comparison area 12 connected to the matrix interference elimination box 5. Inclined channels 9 are provided between the first comparison area 10 and the second comparison area 12 and the reagent confirmation box 7 and the matrix interference elimination box 5.

[0022] Specifically: such as Figure 1 and Figure 2 The reagent confirmation box 7, matrix interference elimination box 5, and experimental box 3 have the same structure, material, and shape. The reagent confirmation box 7, matrix interference elimination box 5, and experimental box 3 include a box body, an end cap 4, a connecting hole at the bottom of the box body, and a plug 13 detachably connected to the connecting hole. The box body is threadedly connected to the end cap 4. When the box body is needed, the end cap 4 needs to be unscrewed.

[0023] Specific implementation process: First, use reagent confirmation chamber 7. Put the same second test reagent into both reagent confirmation chambers 7 and let them sit in the environment for a few minutes. Observe the color of the second test reagent. If there is no color change, it means that the second test reagent is stable and usable. Then clean the two reagent confirmation chambers 7.

[0024] Then, use reagent confirmation box 7. The reagent confirmation box 7 is filled with the first test reagent and the second test reagent respectively. The first test reagent includes buffer, enzyme reagent, substrate and chromogenic agent. The second test reagent includes enzyme reagent, substrate and chromogenic agent.

[0025] The fact that the colors of the two reagent confirmation chambers 7 did not change indicates that the buffer solution was irrelevant and would not react with the enzyme reagent. The buffer solution is stable and reliable, and it is a necessary condition for subsequent sample acquisition, which will be explained later.

[0026] Then, due to the existence of observation error, it is necessary to open the plug 13 located at the bottom of the reagent confirmation box 7. The bottom of the first comparison area 10 is inlaid with a light-shielding plate for reducing the influence of light, so that the reagents can enter the first comparison area 10 for comparison and observation, and once again confirm that there is no color difference between the two groups of reagents. The light-shielding plate can reduce the influence of light and reduce observation error.

[0027] The above confirms the reagent; The two sets of matrix interference elimination boxes 5 are the core of this case: The specific usage is as follows: After determining the reagents, place them in matrix interference exclusion chamber 5. For example, when testing strawberry samples, the testing personnel bring strawberries that have been confirmed to be free of pesticide residues, such as organically certified strawberries or laboratory-grown strawberries that have not been exposed to pesticides. These strawberries need to be opened on the spot, chopped, and the sample extract obtained by ultrasonic extraction with buffer solution is mixed with the reagents in matrix interference exclusion chamber 5, and the color change is observed. Color changes are possible because polyphenols, vitamin C, organic acids, and proteases in fruits and vegetables can non-specifically inhibit enzyme activity. Therefore, two sets of matrix interference exclusion chambers 5 are set up for comparison. If color changes occur in both sets, it indicates that the tested food has its own influence. If only one set shows a color change, the test needs to be repeated.

[0028] Taking the case where matrix interference elimination box 5 remains unchanged, meaning the matrix itself has no effect on the reagents, as an example: Taking strawberries as an example again, find strawberries sold in the market, and then use Experiment 3. The amount of strawberries used in Experiment 3 should be kept consistent. Chop the strawberries, add buffer solution, and extract the supernatant by ultrasonic extraction. Mix the supernatant with enzyme, substrate, and color reagent to form two strawberry sample groups. The two strawberry sample groups are compared with each other.

[0029] If the extract of the sample to be tested contains organophosphates or carbamate pesticide residues, they will bind to the enzyme reagent and inhibit enzyme activity. Once the enzyme activity is inhibited, it cannot effectively decompose the substrate, and the chromogenic reagent will not change color. By detecting the color intensity of the sample group, the degree of inhibition of the enzyme by the pesticide residues can be indirectly reflected, thereby determining whether the pesticide residues exceed the standard.

[0030] If the strawberry sample group shows color development, it indicates the presence of pesticide residues; if no color development occurs, it indicates the absence of pesticide residues. Taking the case where the matrix interference elimination box 5 changes, that is, the matrix itself affects the reagents, as an example; At this point, it is necessary to observe the color change of the strawberry sample group. If the color continues to develop on the basis of the original color, it indicates the presence of pesticide residues. If the color does not continue to develop on the basis of the original color, it indicates the absence of pesticide residues.

[0031] While retaining the advantages of enzyme inhibition methods—rapidness, convenience, and low cost—this device optimizes the design of portable detection devices to reduce detection errors, lower false positive rates, and improve the accuracy and reliability of on-site detection results.

[0032] This device solves the problem of insufficient reliability of test results caused by traditional point-of-care screening methods.

[0033] The above description is merely a preferred embodiment of the present utility model and is not intended to limit the present utility model in any way. Although the present utility model has been disclosed above with reference to a preferred embodiment, it is not intended to limit the present utility model. Any person skilled in the art can make some modifications or alterations to the above-disclosed technical content to create equivalent embodiments without departing from the scope of the present utility model. Any simple modifications, equivalent changes and alterations made to the above embodiments based on the technical essence of the present utility model without departing from the scope of the present utility model shall still fall within the scope of the present utility model.

Claims

1. A portable device for detecting pesticide residues in food, characterized in that, It includes a detection plate, mounting plates fixed to both sides of the detection plate, two sets of reagent confirmation boxes mounted on the detection plate, two sets of matrix interference elimination boxes mounted on the detection plate, and two sets of experimental boxes mounted on the detection plate; The reagent confirmation chamber confirms the stability of the reagents, the matrix interference elimination chamber eliminates the non-specific inhibition of enzyme activity by the matrix of the agricultural product to be tested, and the experimental chamber reacts with pesticide residues in the food to be tested. The detection plate has a contrast groove, and several partitions are installed in the contrast groove. The partitions divide the contrast groove into a first contrast area that is connected to the reagent confirmation box and a second contrast area that is connected to the matrix interference exclusion box. Inclined channels are provided between the first contrast area and the reagent confirmation box and the matrix interference exclusion box.

2. The portable pesticide residue detection device in food according to claim 1, characterized in that, The reagent confirmation box, matrix interference elimination box, and experimental box have the same structure, material, and shape. Each reagent confirmation box, matrix interference elimination box, and experimental box includes a box body, an end cap, a connecting hole at the bottom of the box body, and a plug detachably connected to the connecting hole. The box body and the end cap are threaded together.

3. The portable pesticide residue detection device in food according to claim 2, characterized in that, The bottom of the first comparison area is inlaid with a light-shielding base plate to reduce the impact of light.

4. The portable pesticide residue detection device in food according to claim 1, characterized in that, The mounting plate and the detection plate are integrally formed, and the height of the upper surface of the detection plate is lower than the height of the upper surface of the mounting plate.

5. A portable pesticide residue detection device for food according to claim 2 or 4, characterized in that, The detection plate has slots at both the upper and lower ends for handheld carrying, and the inside of the slots is rounded.

6. A portable pesticide residue detection device in food according to claim 5, characterized in that, A transparent cover plate is detachably connected to the comparison groove.

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