A test strip

Abstract

The embodiment of the application provides a detection test paper. It relates to the technical field of detection. The detection test paper comprises a base layer and a colorimetric detection layer. The colorimetric detection layer is arranged on the base layer, and the colorimetric detection layer comprises a carrier layer and at least two colorimetric detection parts arranged on the carrier layer. The color development time interval of the at least two colorimetric detection parts is less than 10s. Since the at least two colorimetric detection parts are all located on the carrier layer, sample liquid enters the at least two colorimetric detection parts at the same time, there is no time interval for the different colorimetric detection parts to start detection, meanwhile, the color development time interval of the at least two colorimetric detection parts is less than 10s, when the color development time interval of the different colorimetric detection parts is short, the multiple colorimetric detection parts develop color almost at the same time, which enables the user to read the detection results of multiple parameters at the same time point. The synchronism improves the response speed of the overall detection.

Description

Technical Field

[0001] This application relates to the field of testing technology, and in particular to a test strip. Background Technology

[0002] Water quality testing is closely related to human life. Water hardness, pH value, residual chlorine content, heavy metal content, and nitrite content are water quality testing indicators.

[0003] In related technologies, water quality test strips are typically long strips of paper or plastic coated with a series of chemical reagents. Each strip may have multiple test areas (small squares or bands), each used to detect different parameters. During water quality testing, the test strip is immersed in a water sample; the chemical reagents on the strip react with the target substances in the water, causing a color change.

[0004] However, existing water quality test strips have the problem of slow response speed. Summary of the Invention

[0005] This application provides a test strip that improves the response speed of the test strip.

[0006] This application provides a test strip, the test strip comprising:

[0007] grassroots level;

[0008] The colorimetric detection layer is installed on the base layer.

[0009] The colorimetric detection layer includes a carrier layer and at least two colorimetric detection units disposed on the carrier layer; the colorimetric detection units are disposed on the side of the carrier layer closer to the substrate.

[0010] The time interval between the color development of at least two colorimetric detection units is less than 10 seconds.

[0011] In some embodiments of this application, the test strip further includes a cover layer disposed on the side of the colorimetric detection layer away from the base layer.

[0012] In some embodiments of this application, the test strip further includes an impermeable layer disposed between the base layer and the colorimetric detection layer.

[0013] In some embodiments of this application, the test strip further includes an absorbent layer disposed between the impermeable layer and the colorimetric detection layer; the absorbent layer has mounting holes through which the colorimetric detection layer contacts the impermeable layer.

[0014] In some embodiments of this application, the colorimetric detection unit includes a first colorimetric detection unit, which is used to detect water hardness. The materials of the first colorimetric detection unit include methyl thymol blue, masking agent, precipitant, and chelating agent.

[0015] In some embodiments of this application, the masking agent includes sodium potassium tartrate.

[0016] And / or, the precipitant includes sodium hydroxide.

[0017] And / or, chelating agents include ethylenediaminetetraacetic acid (EDTA).

[0018] In some embodiments of this application, the colorimetric detection unit includes a second colorimetric detection unit, which is used to detect the pH value of the water. The materials of the second colorimetric detection unit include a pH indicator and a stabilizer.

[0019] In some embodiments of this application, the pH indicator includes alizarin red.

[0020] And / or, stabilizers include hexadecyltrimethylammonium bromide.

[0021] In some embodiments of this application, the colorimetric detection unit includes a third colorimetric detection unit, which is used to detect the chlorine content in the water. The materials of the third colorimetric detection unit include a colorimetric reagent and a pH reagent.

[0022] In some embodiments of this application, the colorimetric agent includes syringaldehyde azo.

[0023] And / or, pH reagents include citrate-disodium hydrogen phosphate buffer.

[0024] In some embodiments of this application, the colorimetric detection unit includes a fourth colorimetric detection unit, which is used to detect heavy metals in water. The materials of the fourth colorimetric detection unit include a reducing agent, a colorimetric agent, an acid, and potassium iodide.

[0025] In some embodiments of this application, the reducing agent includes ascorbic acid.

[0026] And / or, the colorimetric reagent includes Victoria Blue B.

[0027] And / or, acids include hydrochloric acid.

[0028] In some embodiments of this application, the colorimetric detection unit includes a fifth colorimetric detection unit, which is used to detect nitrite. The materials of the fifth colorimetric detection unit include m-phenylenediamine hydrochloride and pH reagent.

[0029] In some embodiments of this application, the pH reagent includes a citrate-disodium hydrogen phosphate buffer solution.

[0030] In some embodiments of this application, the color development time interval of at least three colorimetric detection units is less than 10 seconds.

[0031] In some embodiments of this application, the color development time interval of at least four colorimetric detection units is less than 10 seconds.

[0032] In some embodiments of this application, the color development time interval of the five colorimetric detection units is less than 10 seconds.

[0033] In some embodiments of this application, the materials of the first colorimetric detection unit include sodium hydroxide, potassium sodium tartrate, methyl thymol blue, and ethylenediaminetetraacetic acid; the mass ratio of sodium hydroxide, potassium sodium tartrate, methyl thymol blue, and ethylenediaminetetraacetic acid is (10-40):(20-50):(10-20):(1-15).

[0034] In some embodiments of this application, the materials of the second colorimetric detection unit include alizarin red and hexadecyltrimethylammonium bromide; the mass ratio of alizarin red to hexadecyltrimethylammonium bromide is (1-10):(1-16).

[0035] In some embodiments of this application, the materials of the fourth colorimetric detection unit include ascorbic acid, potassium iodide, Victoria Blue B, and hydrochloric acid; the mass ratio of ascorbic acid, potassium iodide, Victoria Blue B, and hydrochloric acid is (1-50):(300-700):(1-10):(10000-70000).

[0036] In some embodiments of this application, the colorimetric detection unit includes a liquid addition unit and a colorimetric unit, with the liquid addition unit disposed on the side of the colorimetric unit away from the carrier layer; the colorimetric unit and the liquid addition unit are connected, and the liquid addition unit is used to supply water quality to flow into the colorimetric unit.

[0037] In some embodiments of this application, the liquid addition section has a liquid addition orifice; the colorimetric section has a colorimetric orifice, and the liquid addition orifice is larger than the colorimetric orifice.

[0038] In some embodiments of this application, the size D1 of the liquid addition pore satisfies: 10μm≤D1≤15μm.

[0039] In some embodiments of this application, the thickness P1 of the liquid filling section satisfies: 0.05mm≤P1≤0.15mm.

[0040] In some embodiments of this application, the size of the colorimetric pore is D2, where D2 satisfies: 0.05μm≤D2≤0.15μm.

[0041] In some embodiments of this application, the thickness of the colorimetric part is P2, where P2 satisfies: 1.5mm≤P2≤2.5mm.

[0042] In some embodiments of this application, the liquid addition section includes a first liquid addition section and a plurality of second liquid addition sections, the plurality of second liquid addition sections being arranged at intervals along the outer periphery of the first liquid addition section; the number of colorimetric sections is plurality of, the plurality of colorimetric sections and the plurality of second liquid addition sections being arranged in a one-to-one correspondence.

[0043] In some embodiments of this application, the first liquid filling part is circular in shape, and the second liquid filling part is circular in shape.

[0044] In some embodiments of this application, the diameter of the first liquid filling section is larger than the diameter of the second liquid filling section.

[0045] In some embodiments of this application, the diameter M1 of the first liquid filling part satisfies: 0.5cm≤M1≤1.5cm.

[0046] The diameter of the second liquid filling section is M2, and M2 satisfies: 2.5mm≤M2≤3.5mm.

[0047] In some embodiments of this application, at least one of the following limitations is satisfied:

[0048] The overlay includes release paper;

[0049] The carrier layer includes silicone paper;

[0050] The colorimetric unit includes glass fiber filter paper;

[0051] The liquid dispensing section includes cotton fiber filter paper;

[0052] The impermeable layer includes silicone paper;

[0053] The absorbent layer includes glass fiber filter paper;

[0054] The base layer includes polyethylene terephthalate, polypropylene, and polyethylene.

[0055] In some embodiments of this application, the color development time of the colorimetric detection layer is less than 15 seconds.

[0056] This application provides a test strip, which includes a base layer and a colorimetric detection layer. The colorimetric detection layer is disposed on the base layer and includes a carrier layer and at least two colorimetric detection units disposed on the carrier layer. The colorimetric detection units are disposed on the side of the carrier layer closer to the base layer. The color development time interval between the at least two colorimetric detection units is less than 10 seconds.

[0057] Because at least two colorimetric detection units are located on the carrier layer, the sample solution enters both units simultaneously. There is no time interval between the start of detection at each unit, and the color development time interval between the two units is less than 10 seconds. When the color development time interval is short, multiple detection sites develop color almost simultaneously, allowing users to read the detection results of multiple sample parameters at the same time. This synchronicity improves the overall detection response speed. Since each detection site completes color development almost simultaneously, users can quickly perform comprehensive analysis and judgment of multiple detection indicators. Attached Figure Description

[0058] The accompanying drawings, which are incorporated in and form part of this specification, illustrate embodiments consistent with this application and, together with the description, serve to explain the principles of this application.

[0059] Figure 1 Schematic diagram of the structure of the test strip provided in the embodiments of this application Figure 1 ;

[0060] Figure 2 Schematic diagram of the structure of the test strip provided in the embodiments of this application Figure 2 .

[0061] Explanation of reference numerals in the attached figures:

[0062] 100: Grassroots level;

[0063] 200: Colorimetric detection layer; 210: Carrier layer; 220: Colorimetric detection unit;

[0064] 300: Topcoat;

[0065] 400: Impermeable layer;

[0066] 500: Absorbent layer.

[0067] The accompanying drawings illustrate specific embodiments of this application, which will be described in more detail below. These drawings and descriptions are not intended to limit the scope of the concept in any way, but rather to illustrate the concept of this application to those skilled in the art through reference to particular embodiments. Detailed Implementation

[0068] Exemplary embodiments will now be described in detail, examples of which are illustrated in the accompanying drawings. When the following description relates to the drawings, unless otherwise indicated, the same numbers in different drawings denote the same or similar elements. The embodiments described in the following exemplary embodiments do not represent all embodiments consistent with this application. Rather, they are merely examples of apparatuses and methods consistent with some aspects of this application as detailed in the appended claims.

[0069] Water quality testing is closely related to human life. Water hardness, pH value, residual chlorine content, heavy metal content, and nitrite content are water quality testing indicators.

[0070] High-hardness water is unpalatable and harmful to health, affecting gastrointestinal function. Water pH indicates the acidity or alkalinity of the water source. Residual chlorine is a water quality parameter related to chlorine disinfection; excessively high levels are harmful to health, while excessively low levels reduce water safety. Heavy metals can produce toxic effects even in trace concentrations in water. Nitrites themselves are toxic; excessive use can cause cancer, birth defects, and mutations.

[0071] In related technologies, water quality test strips are typically long strips of paper or plastic coated with a series of chemical reagents. Each strip may have multiple test areas (small squares or bands), each used to detect different parameters. During water quality testing, the test strip is immersed in a water sample; the chemical reagents on the strip react with the target substances in the water, causing a color change.

[0072] In related technologies, water quality test strips complete color development within minutes after the sample solution is added, resulting in a slow response speed.

[0073] Therefore, this application provides a test strip comprising a base layer and a colorimetric detection layer. The colorimetric detection layer is disposed on the base layer and includes a carrier layer and at least two colorimetric detection units disposed on the carrier layer. The colorimetric detection units are disposed on the side of the carrier layer closer to the base layer. The color development time interval between the at least two colorimetric detection units is less than 10 seconds.

[0074] Because at least two colorimetric detection units are located on the carrier layer, the sample solution enters both units simultaneously. There is no time interval between the start of detection at each unit, and the color development time interval between the two units is less than 10 seconds. When the color development time interval is short, multiple detection sites develop color almost simultaneously, allowing users to read the detection results of multiple sample parameters at the same time. This synchronicity improves the overall detection response speed. Since each detection site completes color development almost simultaneously, users can quickly perform comprehensive analysis and judgment of multiple detection indicators.

[0075] The technical solution of this application and how the technical solution of this application solves the above-mentioned technical problems are described in detail below with specific embodiments. These specific embodiments can be combined with each other, and the same or similar concepts or processes may not be described again in some embodiments. The embodiments of this application will now be described with reference to the accompanying drawings.

[0076] Reference Figure 1 and Figure 2 As shown in the figure, this application provides a test strip, including a base layer 100 and a colorimetric detection layer 200.

[0077] A colorimetric detection layer 200 is disposed on a base layer 100. The colorimetric detection layer 200 includes a carrier layer 210 and at least two colorimetric detection units 220 disposed on the carrier layer 210. The colorimetric detection units 220 are disposed on the side of the carrier layer 210 near the base layer 100.

[0078] The color development time interval between at least two colorimetric detection units 220 is less than 10 seconds.

[0079] For example, the base layer 100 provides physical support and structural integrity for the entire test strip, maintaining the shape and stability of the test strip.

[0080] Taking the test strip for testing liquid water as an example, the operator adds the sample liquid to the colorimetric detection layer 200, and the colorimetric detection unit 220 displays the presence or concentration change of the substance in the sample liquid through color change.

[0081] Since at least two colorimetric detection units 220 are located on the carrier layer 210, the sample solution enters both units simultaneously. There is no time interval between the start of detection by different units, and the color development time interval between the two units is less than 10 seconds. When the color development time interval is short, multiple units develop color almost simultaneously, allowing users to read the detection results of multiple sample solution parameters at the same time. This synchronization improves the overall detection response speed. Because each unit completes color development almost simultaneously, users can quickly perform comprehensive analysis and judgment on multiple detection indicators. This is particularly important for detections that require simultaneous consideration of multiple factors, such as multiple pollutants in water.

[0082] Furthermore, the reduced color development time interval means that users do not need to read the results separately after each detection site has developed color, thus reducing waiting and operation time. This improves detection efficiency, especially in situations requiring rapid decision-making. When the color development time interval is short, the impact of changes in external conditions such as light and temperature on the detection results can be minimized because all 220 colorimetric detection units complete color development almost simultaneously, reducing errors caused by time differences.

[0083] Furthermore, when a large number of samples need to be tested, reducing the color development time interval can significantly improve the processing speed of each sample, thereby improving the overall testing efficiency.

[0084] The substances include calcium and magnesium ions, free chlorine, heavy metals, nitrites, and pH.

[0085] In some embodiments, the color development time interval between at least two colorimetric detection units 220 is less than 9 seconds.

[0086] In other embodiments, the color development time interval between at least two colorimetric detection units 220 is less than 8 seconds.

[0087] In some other embodiments, the color development time interval between at least two colorimetric detection units 220 is less than 7 seconds.

[0088] In some other embodiments, the color development time interval between at least two colorimetric detection units 220 is less than 6 seconds.

[0089] In some other embodiments, the color development time interval between at least two colorimetric detection units 220 is less than 5 seconds.

[0090] In some other embodiments, the color development time interval between at least two colorimetric detection units 220 is less than 4 seconds.

[0091] In some other embodiments, the color development time interval between at least two colorimetric detection units 220 is less than 3 seconds.

[0092] In some other embodiments, the color development time interval between at least two colorimetric detection units 220 is less than 2 seconds.

[0093] In some other embodiments, the color development time interval between at least two colorimetric detection units 220 is less than 1 second.

[0094] As one feasible implementation, the colorimetric detection layer 200 has a color development time of less than 15 seconds.

[0095] For example, the colorimetric detection layer 200 has a development time of less than 15 seconds, meaning users can obtain test results in a shorter time. This is especially important in situations requiring rapid decision-making, such as medical diagnosis or on-site testing.

[0096] The rapid colorimetric development of the colorimetric detection layer 200 reduces waiting time and improves the overall efficiency of the test strip detection process, making it suitable for high-throughput detection environments.

[0097] The shorter colorimetric detection layer 200 improves the user experience, especially when multiple or consecutive tests are required, so users don't have to wait a long time for results.

[0098] In some embodiments, the color development time of the colorimetric detection layer 200 is less than 14 seconds.

[0099] In other embodiments, the colorimetric detection layer 200 develops color in less than 13 seconds.

[0100] In some other embodiments, the colorimetric detection layer 200 develops color in less than 12 seconds.

[0101] In some other embodiments, the color development time of the colorimetric detection layer 200 is less than 11 seconds.

[0102] In some other embodiments, the colorimetric detection layer 200 develops color in less than 10 seconds.

[0103] In some other embodiments, the colorimetric detection layer 200 develops color for less than 9 seconds.

[0104] In some other embodiments, the colorimetric detection layer 200 develops color in less than 8 seconds.

[0105] In some other embodiments, the colorimetric detection layer 200 develops color in less than 7 seconds.

[0106] In some other embodiments, the colorimetric detection layer 200 develops color in less than 6 seconds.

[0107] As one feasible implementation, the base layer 100 includes polyethylene terephthalate, polypropylene, and polyethylene.

[0108] Polyethylene terephthalate (PET) possesses mechanical strength and toughness, providing a robust support structure to prevent test strips from tearing or deforming during operation. PET exhibits good resistance to most chemical reagents and samples, and is unlikely to react chemically, thus ensuring the accuracy of test strip results.

[0109] In addition, PET is easy to process into various shapes and sizes, making it suitable for mass production and applications, and providing design flexibility.

[0110] Polypropylene has a low density, which makes the test strips lightweight, easy to carry, and easy to use. Polypropylene also has chemical stability.

[0111] Polyethylene is tough and can withstand a certain degree of physical deformation without damage. Its water-repellent properties ensure that the test strips function properly in humid environments. Polyethylene is resistant to chemicals, ensuring compatibility with the colorimetric test layer 200.

[0112] The thickness of the base layer 100 ranges from 0.1 to 0.5 mm.

[0113] The thickness of the base layer 100 can be 0.1mm, 0.2mm, 0.3mm, 0.4mm, or 0.5mm.

[0114] As one possible implementation, the carrier layer 210 includes silicone paper.

[0115] Silicone paper is highly resistant to most chemicals and is not easily corroded by samples or reagents, ensuring the stability of the colorimetric detection section 220 of the test strip during use.

[0116] The thickness of the carrier layer 210 ranges from 0.1 to 0.5 mm.

[0117] The thickness of the carrier layer 210 can be 0.1mm, 0.2mm, 0.3mm, 0.4mm, or 0.5mm.

[0118] As one possible implementation, the test strip also includes a cover layer 300, which is disposed on the side of the colorimetric detection layer 200 opposite to the base layer 100.

[0119] For example, when the test strip is in storage, the cover layer 300 can effectively protect the colorimetric detection layer 200 from external physical damage, contamination and moisture. The cover layer 300 plays the role of blocking light and oxygen and extending the shelf life of the test strip.

[0120] As one possible implementation, the overlay layer 300 includes release paper.

[0121] Because the test strip requires the top layer 300 to be peeled off during use, and the sample liquid to be added to the colorimetric detection layer 200, the top layer 300 is set as release paper. The release paper is easy to peel off, and the operator can easily peel off the top layer 300 to expose the colorimetric detection layer 200 for testing, which improves the ease of use of the test strip.

[0122] In some embodiments, the cover layer 300 of the test strip is peeled off, and the sample liquid is slowly dripped into the colorimetric detection unit 220 using a plastic pipette. Under the capillary action of the hydrophilic material, the material in the colorimetric detection unit 220 interacts with specific components in the sample liquid and develops color. After a period of time, the color difference is visible to the naked eye. By comparing and analyzing it with the color chart, users can easily determine water quality indicators such as hardness, pH, residual chlorine content, heavy metal content, and nitrite content of the sample to be tested.

[0123] The thickness of the 300 overlay ranges from 0.05 to 0.2 mm.

[0124] The thickness of the overlay 300 can be 0.05mm, 0.06mm, 0.07mm, 0.08mm, 0.09mm, 0.1mm, 0.11mm, 0.12mm, 0.13mm, 0.14mm, or 0.15mm.

[0125] As one feasible implementation, the test strip also includes an impermeable layer 400 disposed between the base layer 100 and the colorimetric detection layer 200.

[0126] For example, the impermeable layer 400 can effectively prevent sample solution from seeping from the colorimetric detection layer 200 into the base layer 100, avoiding cross-contamination between different colorimetric detection sections 220, thereby improving the accuracy of the test results. In addition, the impermeable layer 400 helps ensure that the reagents and sample solutions in each colorimetric detection section 220 are kept within a predetermined area, preventing diffusion and mixing, thereby improving the accuracy and reliability of the test.

[0127] Meanwhile, the 400 impermeable layer can prevent the sample liquid from overflowing into the surrounding environment.

[0128] As one feasible implementation, the impermeable layer 400 includes silicone paper. The silicone paper has waterproof properties, effectively preventing sample solution from penetrating into the base layer 100. This helps ensure that reagents and sample solutions in the colorimetric detection unit 220 remain within a predetermined area, preventing cross-contamination.

[0129] Furthermore, silicone paper is typically chemically inert and does not readily react with sample solutions or reagents. This ensures that the silicone paper will not interfere with the detection reaction, thereby improving the accuracy and reliability of the test results.

[0130] The thickness of the 400 impermeable layer ranges from 0.1 to 0.5 mm.

[0131] The thickness of the 400 impermeable layer can be 0.1mm, 0.2mm, 0.3mm, 0.4mm, or 0.5mm.

[0132] As one feasible implementation, the test strip also includes an absorbent layer 500 disposed between the impermeable layer 400 and the colorimetric detection layer 200.

[0133] The liquid absorption layer 500 has mounting holes, and the colorimetric detection layer 200 contacts the impermeable layer 400 through the mounting holes.

[0134] For example, the absorbent layer 500 can absorb excess sample liquid, preventing it from forming droplets or flowing on the colorimetric detection layer 200, thereby reducing errors and improving the accuracy of the detection results. The presence of the absorbent layer 500 can provide additional physical support to the colorimetric detection layer 200, preventing it from being damaged or deformed during operation.

[0135] Moreover, the absorbent pad can quickly absorb excess sample liquid to prevent sample liquid from spilling and contaminating the surrounding environment.

[0136] The absorbent layer (500) and the impermeable layer (400) provide double protection to prevent the sample solution from spilling into the surrounding environment.

[0137] The thickness of the absorbent layer 500 ranges from 0.1 to 0.5 mm.

[0138] The thickness of the absorbent layer 500 can be 0.1mm, 0.2mm, 0.3mm, 0.4mm, or 0.5mm.

[0139] The liquid absorption layer 500 has liquid absorption pores with a diameter ranging from 2.0 to 3.5 μm.

[0140] The liquid absorption pore size of the liquid absorption layer 500 can be 2.1μm, 2.2μm, 2.3μm, 2.4μm, 2.5μm, 2.6μm, 2.7μm, 2.8μm, or 2.9μm.

[0141] As one possible implementation, the absorbent layer 500 includes glass fiber filter paper.

[0142] Glass fiber filter paper has a capillary action, which allows it to quickly absorb excess sample solution and prevent spillage. It also has high mechanical strength, providing good physical support during operation and preventing tearing or deformation.

[0143] As one feasible implementation, the colorimetric detection unit 220 includes a first colorimetric detection unit for detecting water hardness. The materials of the first colorimetric detection unit include methyl thymol blue, masking agent, precipitant, and chelating agent.

[0144] Methylthymol blue is used as a colorimetric reagent in detection reactions to react with other compounds to generate visible color changes, thereby enabling quantitative or qualitative analysis.

[0145] Masking agents are used to selectively mask interfering ions, ensuring that the detection results primarily reflect the concentration of hardness ions in the water. By masking other metal ions that may interfere with detection, masking agents improve the accuracy and reliability of the detection.

[0146] Precipitants are used to precipitate specific metal ions, such as iron ions, thereby reducing their interference with detection results. By removing interfering ions, precipitants can enhance the color development of methyl thymol blue, making the color change more obvious and easier to detect.

[0147] Chelating agents are used to chelate target ions for accurate and efficient determination.

[0148] In the first colorimetric detection section, methyl thymol blue is used. Methyl thymol blue is generally considered a low-toxicity compound. At conventional concentrations, it has low toxicity to humans. Compared to test strips in related technologies that use azo reagents, the test strip provided in this application reduces the harm of the colorimetric detection layer 200 to humans and improves the safety of the test strip by replacing the azo reagent with methyl thymol blue.

[0149] As one feasible implementation, the precipitant includes sodium hydroxide.

[0150] Sodium hydroxide is used to precipitate certain metal ions, especially those that may interfere with hardness testing, such as iron and aluminum. By removing interfering ions, sodium hydroxide can enhance the color development of methyl thymol blue, making the color change more obvious and easier to detect.

[0151] As one feasible implementation, the masking agent includes sodium potassium tartrate.

[0152] Potassium sodium tartrate (Rochelle salt) is used as a masking agent for heavy metal ions. It can mask interfering ions in the sample solution, thereby eliminating their influence on water hardness detection.

[0153] As one feasible implementation, the chelating agent includes ethylenediaminetetraacetic acid (EDTA).

[0154] Ethylenediaminetetraacetic acid (EDTA) is a commonly used chelating agent that effectively complexes calcium and magnesium ions in water, which are the main components of water hardness. By complexing these ions, EDTA can help accurately measure water hardness.

[0155] As one feasible implementation, the materials of the first colorimetric detection unit include sodium hydroxide, potassium sodium tartrate, methyl thymol blue, and ethylenediaminetetraacetic acid; the mass ratio of sodium hydroxide, potassium sodium tartrate, methyl thymol blue, and ethylenediaminetetraacetic acid is 10-40:20-50:10-20:1-15.

[0156] For example, the mass ratio of sodium hydroxide, potassium sodium tartrate, methyl thymol blue, and ethylenediaminetetraacetic acid is set to satisfy 10-40:20-50:10-20:1-15. This helps the material of the first colorimetric detection unit to play its role in the colorimetric reaction. This mass ratio of sodium hydroxide, potassium sodium tartrate, methyl thymol blue, and ethylenediaminetetraacetic acid ensures the accuracy of methyl thymol blue color development. At the same time, when the mass ratio of the masking agent, precipitant, and chelating agent meets this range, interfering ions are effectively masked and precipitated, while target ions are chelated, ensuring the accuracy and reliability of the detection.

[0157] For example, a first colorimetric detection solution is dropped onto glass fiber filter paper and dried to form a first colorimetric detection section.

[0158] The first colorimetric detection solution includes an aqueous solution of sodium hydroxide, an aqueous solution of potassium sodium tartrate, an aqueous solution of methyl thymol blue, and an aqueous solution of ethylenediaminetetraacetic acid.

[0159] As one feasible implementation, the colorimetric detection unit 220 includes a second colorimetric detection unit for detecting the pH value of water. The materials of the second colorimetric detection unit include a pH indicator and a stabilizer.

[0160] For example, a pH indicator is a compound that displays different colors at different pH values. Its function is to indicate the acidity or alkalinity of a solution through color changes.

[0161] Stabilizers are used to ensure the dispersibility and stability of pH indicators in solution, preventing degradation or precipitation during storage or use. By improving indicator stability, stabilizers ensure uniformity and repeatability of color changes, thus enhancing the reliability of detection.

[0162] As one feasible implementation, the pH indicator includes alizarin red.

[0163] Alizarin red is a commonly used pH indicator that exhibits a clear color change across different pH ranges. The color change of alizarin red is significant under both acidic and alkaline conditions, facilitating visual identification and colorimetric analysis.

[0164] As one feasible implementation, the stabilizer includes hexadecyltrimethylammonium bromide.

[0165] Hexadecyltrimethylammonium bromide (CTAB) is a cationic surfactant that can improve the stability of Alizarin Red. By altering interfacial properties, CTAB can enhance the sensitivity of the colorimetric detection unit 220 to pH changes, thereby improving detection accuracy. CTAB also helps improve the chemical stability of the detection unit and reduces the interference of environmental factors on the detection results.

[0166] The combination of these materials enables the second colorimetric detection unit to effectively detect the pH value of water. Alizarin Red provides the color development mechanism, while hexadecyltrimethylammonium bromide ensures the stability and accuracy of the detection.

[0167] In one feasible implementation, the materials of the second colorimetric detection unit include alizarin red and hexadecyltrimethylammonium bromide; the mass ratio of alizarin red to hexadecyltrimethylammonium bromide is 1-10:1-16. Within this mass ratio range, alizarin red exhibits significant color changes at different pH values, facilitating visual identification and colorimetric analysis. An appropriate concentration of alizarin red ensures the clarity and contrast of the color changes. CTAB, as a stabilizer, effectively improves the stability of alizarin red in solution within this ratio range, preventing its degradation or precipitation. The presence of CTAB ensures the chemical stability of the indicator during storage and use.

[0168] For example, the second colorimetric detection solution is dropped onto glass fiber filter paper and dried to form the second colorimetric detection section.

[0169] The second colorimetric detection solution includes an aqueous solution of alizarin red and an aqueous solution of hexadecyltrimethylammonium bromide.

[0170] As one feasible implementation, the colorimetric detection unit 220 includes a third colorimetric detection unit for detecting the chlorine content in water. The materials of the third colorimetric detection unit include a colorimetric reagent and a pH reagent.

[0171] For example, the colorimetric reagent reacts with chlorine in water, causing a color change. This colorimetric reaction can be used for qualitative or quantitative analysis of chlorine concentration. A pH reagent is used to maintain the pH of the solution within a stable range to ensure optimal reaction conditions for the colorimetric reagent. By providing a stable pH environment, the pH reagent ensures the consistency and repeatability of the colorimetric reaction, improving the reliability of the detection.

[0172] As one feasible implementation, the color developer includes syringaldehyde azo.

[0173] For example, eugenaldehyde is a colorimetric reagent that reacts with chlorine to form a colored compound. This colorimetric reaction is the basis of colorimetric detection, which uses color changes to quantitatively or qualitatively analyze the chlorine content in water.

[0174] As one feasible implementation, the pH reagent includes a citrate-disodium hydrogen phosphate buffer solution. This citrate-disodium hydrogen phosphate buffer system is used to control the pH value of the colorimetric reaction. An appropriate pH value is crucial to ensuring the sensitivity and accuracy of the colorimetric reaction. The combination of citrate and disodium hydrogen phosphate provides a stable buffer environment, optimizing the reaction conditions.

[0175] For example, the third colorimetric detection solution is dropped onto glass fiber filter paper and dried to form the third colorimetric detection section.

[0176] The third colorimetric detection solution includes eugenol azohydride solution and citrate-disodium hydrogen phosphate buffer solution.

[0177] As one feasible implementation, the colorimetric detection unit 220 includes a fourth colorimetric detection unit for detecting heavy metals in water. The materials of the fourth colorimetric detection unit include a reducing agent, a colorimetric agent, an acid, and potassium iodide.

[0178] For example, reducing agents can reduce heavy metal ions, thus providing protection and masking.

[0179] Colorimetric reagents can react with specific heavy metal ions, resulting in a color change. This colorimetric reaction can be used for qualitative or quantitative analysis of heavy metal concentrations.

[0180] Acids are used to adjust the pH of the solution, providing an acidic environment to promote the reaction between the reducing agent and the colorimetric agent.

[0181] Potassium iodide can form complexes with certain heavy metal ions, enhancing the sensitivity and specificity of colorimetric reactions.

[0182] As one feasible implementation method, the reducing agent includes ascorbic acid.

[0183] For example, ascorbic acid is an effective reducing agent that can reduce certain heavy metal ions to a more detectable form. It can prevent other components from being oxidized, thereby improving the stability of detection.

[0184] As one feasible implementation, the color developer includes Victoria Blue B.

[0185] Victoria Blue B is a dye used in colorimetric reactions. It reacts with heavy metal ions to produce a color change, facilitating visual detection. It provides good color contrast, making detection results easier to observe and analyze.

[0186] As one possible implementation method, the acid includes hydrochloric acid.

[0187] Hydrochloric acid is used to adjust the pH of a solution, providing a suitable acidic environment to promote the dissolution and reaction of certain heavy metals. In some chemical reactions, an acidic environment is necessary to ensure the reaction proceeds and to achieve the desired colorimetric effect.

[0188] As one feasible implementation, the materials of the fourth colorimetric detection unit include ascorbic acid, potassium iodide, Victoria Blue B, and hydrochloric acid; the mass ratio of ascorbic acid, potassium iodide, Victoria Blue B, and hydrochloric acid is 1-50:300-700:1-10:10000-70000. Within this mass ratio range, ascorbic acid can effectively reduce heavy metal ions, promoting the occurrence of colorimetric reactions. An appropriate amount of ascorbic acid ensures the high efficiency of the reduction process while avoiding potential side reactions from excessive use; Victoria Blue B can react with heavy metal ions to provide good color contrast, facilitating visual detection and analysis. An appropriate concentration of the colorimetric reagent ensures the clarity and contrast of color changes. Hydrochloric acid provides a suitable acidic environment, promoting the dissolution and reaction of heavy metals; sufficient acidic conditions ensure the smooth progress of the colorimetric reaction, improving the sensitivity and accuracy of detection; potassium iodide can form complexes with certain heavy metal ions, enhancing the sensitivity and specificity of the colorimetric reaction. An appropriate amount of potassium iodide ensured the stability of the complex and the specificity of the reaction.

[0189] For example, the fourth colorimetric detection solution is dropped onto glass fiber filter paper and dried to form the fourth colorimetric detection section.

[0190] The fourth colorimetric detection solution includes ascorbic acid aqueous solution, potassium iodide aqueous solution, Victoria Blue B aqueous solution, and hydrochloric acid.

[0191] As one possible implementation, the colorimetric detection unit 220 includes a fifth colorimetric detection unit for detecting nitrite, and the materials of the fifth colorimetric detection unit include m-phenylenediamine hydrochloride and pH reagent.

[0192] m-Phenylenediamine hydrochloride reacts with diazo compounds to form colored azo compounds. The color change resulting from this reaction can be used to quantitatively determine the concentration of nitrite, typically appearing as pink or red.

[0193] The pH reagent provides a stable pH environment, ensuring the consistency and reproducibility of the reaction between m-phenylenediamine hydrochloride and diazo compounds, thus improving the reliability of the detection.

[0194] As one feasible implementation, the pH reagent includes a citrate-disodium hydrogen phosphate buffer solution.

[0195] The citrate-disodium hydrogen phosphate buffer system is used to adjust and maintain the pH of the solution. An appropriate pH is crucial for ensuring the accuracy and sensitivity of colorimetric reactions. The combination of citrate and disodium hydrogen phosphate provides a stable buffer environment, preventing pH fluctuations from affecting the detection results.

[0196] For example, the fifth colorimetric detection solution is dropped onto glass fiber filter paper and dried to form the fifth colorimetric detection section.

[0197] The fifth colorimetric detection solution includes an aqueous solution of m-phenylenediamine hydrochloride and a citrate-disodium hydrogen phosphate buffer solution.

[0198] The test strip provided in this embodiment can optimize reaction conditions by changing the proportions of different materials in the colorimetric detection unit 220. Controlling the material proportions lowers the activation energy of the reaction, thereby accelerating the reaction rate. Adjusting the proportions of different materials affects the overall chemical environment of the test strip, making it more suitable for the rapid progress of the target reaction. By accelerating the chemical reaction rate, the collision frequency between molecules is increased, thereby accelerating the reaction rate and improving the response speed of the colorimetric detection unit 220. This means that detection results can be obtained in a shorter time, improving detection efficiency.

[0199] By designing the type, concentration, and pH of the material in the colorimetric detection unit 220, the response speed of the colorimetric detection unit 220 can be improved, and each colorimetric detection unit 220 completes color development almost simultaneously, reducing the time interval between color development of different colorimetric detection units 220. In particular, the color development time interval between at least two colorimetric detection units 220 is less than 10 seconds, thus improving the response speed of the colorimetric detection unit 220.

[0200] As one feasible implementation, the color development time interval between at least two colorimetric detection units 220 is less than 10 seconds.

[0201] For example, the color development time interval between any two of the first colorimetric detection unit, the second colorimetric detection unit, the third colorimetric detection unit, the fourth detection unit, and the fifth detection unit is less than 10 seconds.

[0202] As one feasible implementation, the color development time interval of at least three colorimetric detection units 220 is less than 10 seconds.

[0203] For example, the color development time interval of at least three colorimetric detection units can be less than 10s, less than 9s, less than 8s, less than 7s, less than 6s, less than 5s, less than 4s, less than 3s, less than 2s, or less than 1s.

[0204] In some embodiments, the color development time interval between the first colorimetric detection unit, the second colorimetric detection unit, and the third colorimetric detection unit is less than 10 seconds.

[0205] In other embodiments, the color development time interval between the first colorimetric detection unit, the second colorimetric detection unit, and the fourth colorimetric detection unit is less than 10 seconds.

[0206] In some other embodiments, the color development time interval between the first colorimetric detection unit, the second colorimetric detection unit, and the fifth colorimetric detection unit is less than 10 seconds.

[0207] In some other embodiments, the color development time interval between the second colorimetric detection unit, the third colorimetric detection unit, and the fourth colorimetric detection unit is less than 10 seconds.

[0208] In some other embodiments, the color development time interval between the second colorimetric detection unit, the third colorimetric detection unit, and the fifth colorimetric detection unit is less than 10 seconds.

[0209] In some other embodiments, the color development time interval between the third, fourth, and fifth colorimetric detection units is less than 10 seconds.

[0210] As one feasible implementation, the color development time interval of at least four colorimetric detection units 220 is less than 10 seconds.

[0211] For example, the color development time interval of at least four colorimetric detection units can be less than 10s, less than 9s, less than 8s, less than 7s, less than 6s, less than 5s, less than 4s, less than 3s, less than 2s, or less than 1s.

[0212] In some embodiments, the color development time interval between the first colorimetric detection unit, the second colorimetric detection unit, the third colorimetric detection unit, and the fourth colorimetric detection unit is less than 10 seconds.

[0213] In other embodiments, the color development time interval between the first colorimetric detection unit, the second colorimetric detection unit, the third colorimetric detection unit, and the fifth colorimetric detection unit is less than 10 seconds.

[0214] In some other embodiments, the color development time interval between the second, third, fourth, and fifth colorimetric detection units is less than 10 seconds.

[0215] As one feasible implementation, the color development time interval of the five colorimetric detection units 220 is less than 10 seconds.

[0216] For example, the color development time interval of the five colorimetric detection units can be less than 10s, less than 9s, less than 8s, less than 7s, less than 6s, less than 5s, less than 4s, less than 3s, less than 2s, or less than 1s.

[0217] In some embodiments, the color development time interval between the first colorimetric detection unit, the second colorimetric detection unit, the third colorimetric detection unit, the fourth colorimetric detection unit, and the fifth colorimetric detection unit is less than 10 seconds.

[0218] As one feasible implementation, the colorimetric detection unit 220 includes a liquid addition unit and a colorimetric unit, with the liquid addition unit disposed on the side of the colorimetric unit away from the carrier layer 210; the colorimetric unit and the liquid addition unit are connected, and the liquid addition unit is used to supply water quality to flow into the colorimetric unit.

[0219] For example, the carrier layer 210 is provided with an opening, and the liquid filling part is provided corresponding to the opening.

[0220] The liquid addition section is the inlet where the sample solution enters the test strip. The colorimetric section is the area where the sample solution and reagents react chemically. Here, the material of the colorimetric detection section 220 reacts with substances in the sample solution, producing a color change.

[0221] This layout allows the sample solution to flow smoothly from the dispensing section into the colorimetric section, ensuring sufficient contact and reaction. This design utilizes gravity and capillary action to promote sample solution flow.

[0222] As one feasible implementation, the liquid dispensing section includes cotton fiber filter paper.

[0223] Cotton fibers have excellent liquid absorption properties, enabling them to quickly absorb and retain sample solutions. This property ensures that the sample solution can rapidly penetrate the dispensing section and flow further to the colorimetric section.

[0224] The structure of cotton fibers helps to distribute liquids evenly, reducing the risk of liquid accumulation and uneven distribution. This is crucial for ensuring the consistency and accuracy of test results.

[0225] As a natural material, cotton fibers typically have good biocompatibility and low chemical reactivity, making it less likely to introduce interfering substances and ensuring the purity of the testing process.

[0226] Cotton fiber filter paper has strong capillary action, which can effectively guide the flow of liquid. This property allows the sample liquid to flow smoothly from the dispensing section to the colorimetric section, supporting automated and unforced liquid transfer.

[0227] As one feasible implementation, the colorimetric unit includes glass fiber filter paper.

[0228] Glass fiber filter paper exhibits excellent capillary action, enabling rapid absorption and distribution of sample liquid. This property ensures that the sample liquid can quickly penetrate the material of the colorimetric detection unit 220, promoting rapid reaction and color development. Due to its fibrous structure, glass fiber filter paper can uniformly distribute liquid, reducing the risk of liquid accumulation and uneven distribution, thereby improving the accuracy and consistency of test results.

[0229] Glass fiber materials exhibit good resistance to most chemical reagents and are unlikely to react with sample solutions or reagents. This ensures that no additional chemical interference is introduced during the testing process, thus improving the reliability of the results.

[0230] Glass fiber filter paper typically has low background interference characteristics and will not significantly affect the colorimetric reaction, thereby improving the sensitivity of detection.

[0231] In one feasible implementation, the liquid filling section includes a first liquid filling section and a plurality of second liquid filling sections, which are spaced apart along the outer periphery of the first liquid filling section.

[0232] There are multiple colorimetric units, and multiple second liquid addition units are set up one-to-one.

[0233] The carrier layer 210 is provided with a first opening and a second opening, the first opening and the first liquid addition section are provided correspondingly, and the second opening and the second liquid addition section are provided correspondingly.

[0234] The sample solution enters the colorimetric detection section 220 through the first and second openings.

[0235] When the sample solution is added to the first liquid addition section, it automatically permeates to multiple second liquid addition sections around the edge of the first liquid addition section under capillary action, and finally permeates into the colorimetric section that is in close contact with it and develops color.

[0236] By centrally adding sample solution in the first dispensing section, the sample solution can be automatically and evenly distributed to multiple second dispensing sections under capillary action. This design ensures that each colorimetric section receives the same volume of sample solution, reducing detection errors caused by uneven liquid distribution. Simultaneously, the sample solution permeates multiple colorimetric sections, allowing multiple detection reactions to proceed synchronously.

[0237] As one feasible implementation, the liquid addition section has liquid addition pores; the colorimetric section has colorimetric pores, and the liquid addition pores are larger than the colorimetric pores.

[0238] For example, the larger pore size allows for rapid absorption and guidance of the sample solution into the dispensing section. This design facilitates rapid sample solution introduction and reduces waiting time; the smaller colorimetric pore size slows down the sample solution flow rate, ensuring sufficient residence time for the sample solution in the colorimetric section to complete the chemical reaction and color development process.

[0239] By controlling the flow rate and residence time of the sample solution in the colorimetric section, the sensitivity of the detection reaction can be improved, ensuring sufficient chemical reaction to obtain clear colorimetric results.

[0240] As one feasible implementation, the size D1 of the liquid addition pore satisfies: 10μm≤D1≤15μm.

[0241] For example, a liquid addition pore size in the range of 10-15 μm can provide a moderate flow rate, rapidly absorb the sample liquid, help control the liquid flow rate, ensure that the liquid can penetrate evenly into the colorimetric unit, and support a stable detection reaction.

[0242] Conversely, when the liquid addition pore size is less than 10 μm, the smaller pore size may result in slower sample flow, increasing detection time and making it unsuitable for applications requiring rapid detection. Smaller pores may also be more easily clogged by particulate matter or high-viscosity samples, affecting liquid flow and detection efficiency.

[0243] When the size of the liquid addition pores is greater than 10 μm, the large pore size may lead to uneven distribution of the sample liquid, especially when the sample liquid volume is small, which will affect the consistency of the test results.

[0244] For example, D1 can be 10μm, 11μm, 12μm, 13μm, 14μm, or 15μm.

[0245] As one feasible implementation, the thickness P1 of the liquid addition section satisfies: 0.05mm≤P1≤0.15mm.

[0246] For example, when the thickness of the liquid dispensing section is between 0.05 mm and 0.15 mm, the liquid dispensing section provides moderate liquid absorption capacity, effectively absorbing and retaining the sample solution while avoiding sample waste due to over-absorption. Simultaneously, the moderate thickness of the liquid dispensing section helps control the liquid flow rate, ensuring that the liquid can uniformly penetrate the colorimetric unit and support a stable detection reaction.

[0247] Conversely, when the thickness of the liquid addition section is less than 0.05 mm, the thinner liquid addition section may limit its liquid absorption capacity, resulting in insufficient absorption of the sample liquid and affecting the subsequent detection process.

[0248] At the same time, a thinner liquid dispensing section may be more prone to tearing or deformation during operation, affecting the reliability and repeatability of the test.

[0249] When the thickness of the liquid addition section is greater than 0.15 mm, the thicker liquid addition section may lead to excessive absorption of sample solution, increasing the amount of sample solution used and causing waste.

[0250] A thicker liquid dispensing section may slow down the flow rate of the sample solution and prolong the detection time, making it unsuitable for detection applications that require a rapid response.

[0251] For example, P1 can be 0.06mm, 0.07mm, 0.08mm, 0.09mm, 0.10mm, 0.11mm, or 0.12mm.

[0252] As one feasible implementation, the size of the colorimetric pore is D2, where D2 satisfies: 0.05μm≤D2≤0.15μm.

[0253] For example, when the colorimetric pore size is in the range of 0.05-0.15 μm, it ensures that the sample solution has sufficient residence time in the colorimetric section for adequate chemical reaction and color development. A suitable pore size helps improve the efficiency of the chemical reaction, making the color development process more stable and reliable, suitable for applications requiring precise detection.

[0254] Conversely, when the colorimetric pore size is less than 0.05 μm, the small pore size may cause the sample liquid to flow too slowly, increasing the detection time and making it unsuitable for applications requiring rapid detection. Too small a pore size may also cause the sample liquid to remain for too long, affecting the dynamics of the reaction and the timeliness of the detection results.

[0255] When the colorimetric pore size is greater than 0.15 μm, the large pore size may cause the sample liquid to flow too quickly, reducing the residence time in the colorimetric section, thus affecting the sufficiency of the colorimetric reaction and the accuracy of the detection results. At the same time, when the colorimetric pore size is too large, it is not conducive to the material supporting the colorimetric detection section 220.

[0256] For example, D2 can be 0.06μm, 0.07μm, 0.08μm, 0.09μm, 0.10μm, or 0.11μm.

[0257] As one feasible implementation, the thickness of the colorimetric part is P2, where P2 satisfies: 1.5mm≤P2≤2.5mm.

[0258] For example, when the thickness of the colorimetric section is in the range of 1.5-2.5 mm, the appropriate thickness ensures that the sample solution has sufficient volume in the colorimetric section for adequate chemical reaction, thereby improving the integrity and accuracy of the colorimetric reaction.

[0259] The appropriate thickness allows the colorimetric section to hold enough sample solution, ensuring the repeatability and reliability of the test.

[0260] Conversely, when the thickness of the colorimetric part is less than 1.5 mm, the thinner colorimetric part may limit the volume of the sample solution, resulting in insufficient chemical reaction, which in turn affects the integrity of the color development and the accuracy of the detection results.

[0261] When the thickness of the colorimetric part is greater than 2.5 mm, the excessively thick colorimetric part may slow down the diffusion rate of the sample solution and increase the detection time, especially in applications that require rapid detection.

[0262] For example, P2 can be 1.6mm, 1.7mm, 1.8mm, 1.9mm, 2.0mm, 2.1mm, or 2.2mm.

[0263] As one feasible implementation, the first liquid filling section is circular in shape, and the second liquid filling section is circular in shape.

[0264] For example, the circular structure facilitates the uniform distribution of the sample solution. The sample solution can naturally diffuse in all directions within the circular area, ensuring that the sample solution evenly covers the entire dispensing section.

[0265] The circular design reduces obstructions and dead zones in the flow of sample solution, allowing the liquid to flow more smoothly from the first liquid addition section to the second liquid addition section, and finally into the colorimetric section.

[0266] The circular structure reduces the impact of edge effects, preventing sample liquid from accumulating or flowing poorly at the edges, thereby improving the accuracy and consistency of detection.

[0267] As one feasible implementation, the diameter of the first liquid filling section is larger than the diameter of the second liquid filling section.

[0268] For example, the larger diameter of the first dispensing section means that it can hold more sample solution. This ensures that enough sample solution can be dispensed into multiple second dispensing sections to meet the needs of each colorimetric section.

[0269] The larger first dispensing section can more evenly distribute the sample solution to multiple second dispensing sections, reducing inconsistencies in detection caused by insufficient sample solution.

[0270] Users only need to add the sample solution once in the first liquid addition section, instead of adding it to each of the second liquid addition sections one by one, which simplifies the operation.

[0271] The size difference between the larger first filling section and the smaller second filling section naturally creates a pressure differential. This pressure differential helps to propel the sample solution from the first filling section to the second filling section, supporting automated liquid transfer.

[0272] The pressure difference helps overcome the resistance encountered by the liquid during flow, ensuring that the liquid can reach the second filling section smoothly and quickly.

[0273] As one feasible implementation, the diameter M1 of the first liquid addition section satisfies: 0.5cm≤M1≤1.5cm.

[0274] The diameter of the second liquid filling section is M2, and M2 satisfies: 2.5mm≤M2≤3.5mm.

[0275] For example, when the diameter of the first liquid filling section is between 0.5 and 1.5 cm, the second liquid filling section can hold enough sample liquid to ensure that sufficient sample liquid is provided to the second liquid filling section.

[0276] Conversely, when the diameter of the first liquid filling section is less than 0.5 cm, the first liquid filling section has insufficient capacity and cannot effectively supply liquid to the second liquid filling section.

[0277] When the diameter of the first liquid addition section is greater than 1.5 cm, it may lead to excessive sample liquid usage and increased waste.

[0278] When the diameter of the second liquid addition section is between 2.5 and 3.5 mm, the appropriate diameter helps to ensure the uniform distribution and flow of the sample liquid, thereby improving the consistency of the test results.

[0279] Conversely, when the diameter of the second liquid addition section is less than 2.5 mm, it may affect the uniform flow of the sample liquid.

[0280] When the diameter of the second liquid addition section is greater than 3.5 mm, it may increase the amount of sample solution used, resulting in waste.

[0281] The length of the 300 overlay ranges from 5 to 7 cm, and the width ranges from 4 to 6 cm.

[0282] The carrier layer 210 has a length ranging from 3 to 5 cm and a width ranging from 2 to 4 cm. To ensure smooth entry of the sample solution into the dispensing section, a first circular hole with a diameter of 0.8 cm is formed in the center of the carrier layer 210. Five second circular holes with a diameter of 3 mm are evenly distributed at a distance of 1 mm from the outer edge of the first circular hole. The carrier layer 210 is adhered to the colorimetric detection section 220 using waterproof medical double-sided tape.

[0283] The absorbent layer 500 includes two first absorbent strips and two second absorbent strips. The length of the first absorbent strip ranges from 3 to 5 cm, and the width ranges from 0.2 to 0.4 cm; the length of the second absorbent strip ranges from 2 to 3 cm, and the width ranges from 0.2 to 0.4 cm. The first and second absorbent strips are connected to form the absorbent layer 500. The first and second absorbent strips are distributed around the carrier layer 210.

[0284] The length of the 400mm impermeable layer ranges from 3 to 5cm, and the width ranges from 2 to 4cm.

[0285] The base layer 100 has a length ranging from 5-7 cm and a width ranging from 4-6 cm. The side of the base layer 100 facing the impermeable layer 400 is adhesive. The carrier layer 210 and the impermeable layer 400 are tightly connected.

[0286] The following examples further illustrate this point:

[0287] Example 1: The first colorimetric detection solution was dropped onto glass fiber filter paper and dried to form the first colorimetric detection section. The first colorimetric detection solution consisted of 2 μL of 0.8 mg / mL solution. -1 Sodium hydroxide aqueous solution, 2 μL 1 mg mL -1 Potassium sodium tartrate aqueous solution, 3 μL 0.6 mg mL -1 Methyl thymol blue aqueous solution, 3 μL 0.4 mg mL -1 Aqueous solution of ethylenediaminetetraacetic acid.

[0288] The second colorimetric detection solution is dropped onto glass fiber filter paper and allowed to dry to form the second colorimetric detection section. The second colorimetric detection solution comprises 8 μL of 5 mg / mL solution. -1 Alizarin Red aqueous solution, 2 μL 10 mg mL -1 Aqueous solution of hexadecyltrimethylammonium bromide.

[0289] The third colorimetric detection solution is dropped onto glass fiber filter paper and allowed to dry to form the third colorimetric detection section. The third colorimetric detection solution consists of 8 μL of 2.5 mg / mL solution. -1 Syringaldehyde azohydric aqueous solution, 2 μL 1 mol L -1 Citric acid-disodium hydrogen phosphate buffer solution.

[0290] The fourth colorimetric detection solution is dropped onto glass fiber filter paper and allowed to dry to form the fourth colorimetric detection section. The fourth colorimetric detection solution comprises 3 μL of 1 mg / mL... -1 Ascorbic acid aqueous solution, 3 μL 13 mg mL -1 Potassium iodide aqueous solution, 3 μL 0.002% Victoria Blue B aqueous solution, 3 μL 31% hydrochloric acid.

[0291] The fifth colorimetric detection solution is dropped onto glass fiber filter paper and allowed to dry to form the fifth colorimetric detection section. The fifth colorimetric detection solution consists of 4 μL of 10 mg / mL... -1 m-phenylenediamine hydrochloride aqueous solution, 6 μL 1 mol L -1 Citric acid-disodium hydrogen phosphate buffer solution.

[0292] The liquid to be tested is added to the colorimetric detection layer 200; the color development time of the five colorimetric detection units 220 is recorded. The first color development time is defined as the color development time of the colorimetric detection unit 220 that develops the first color, and the second color development time is defined as the color development time of the colorimetric detection unit 220 that develops the color later than the first color development time.

[0293] Example 2: The difference between Example 2 and Example 1 is that the volume of the liquid to be tested is different. In Example 2, the liquid to be tested is added dropwise to the colorimetric detection layer 200 until the colorimetric detection layer 200 changes color, and the volume of the liquid to be tested is recorded.

[0294] Example 3: Example 3 differs from Example 1 in that the test paper is immersed in the liquid to be tested, and the material of the colorimetric detection unit 220 is observed to see if it falls off.

[0295] Example 4: The difference between Example 4 and Example 1 is that in Example 4, the test strip is exposed to the environment, and the color development performance of the test strip is checked daily to see if it is abnormal. The date on which the color development performance of the test strip becomes abnormal is the shelf life, and the shelf life of the test strip is recorded.

[0296] Comparative Example 1: Unlike Example 1, in Comparative Example 1, the liquid to be tested was added to commercially available test strip 1, and the color development time of commercially available test strip 1 was recorded.

[0297] Comparative Example 2: Unlike Example 1, in Comparative Example 2, the liquid to be tested was added to commercially available test strip 2, and the color development time of commercially available test strip 2 was recorded.

[0298] Comparative Example 3: The difference from Example 2 is that the volume of the test liquid added to the commercially available test strip 1 is different. In Comparative Example 3, the test liquid was added drop by drop to the commercially available test strip 1 until the commercially available test strip 1 changed color, and the volume of the test liquid was recorded.

[0299] Comparative Example 4: The difference from Example 2 is that the volume of the test liquid added to the commercially available test strip 2 is different. In Comparative Example 4, the test liquid was added drop by drop to the commercially available test strip 2 until the commercially available test strip 2 changed color, and the volume of the test liquid was recorded.

[0300] Comparative Example 5: The difference from Example 3 is that in Comparative Example 5, commercially available test strip 1 was immersed in the liquid to be tested, and the material of commercially available test strip 1 was observed to see if it peeled off.

[0301] Comparative Example 6: The difference from Example 3 is that in Comparative Example 6, commercially available test strip 2 was immersed in the liquid to be tested, and the material of commercially available test strip 2 was observed to see if it peeled off.

[0302] Comparative Example 7: The difference from Example 4 is that Comparative Example 7 exposed commercially available test strip 1 to the environment and recorded the shelf life of commercially available test strip 1.

[0303] Comparative Example 8: The difference from Example 4 is that Comparative Example 8 exposed the commercially available test strip 2 to the environment and recorded the shelf life of the commercially available test strip 2.

[0304] Among them, the materials for the nitrite detection unit in commercially available test strip 1 include: tartaric acid, sulfonamide, and naphthylethylenediamine hydrochloride. The materials for the heavy metal detection unit include: potassium hydroxide, ethanol, and p-nitrobenzene diazoaminoazobenzene. The materials for the water hardness detection unit include: Chrome Black T, alizarin, polyvinylpyrrolidone, and phosphate buffer. The materials for the residual chlorine detection unit include: 3,3',5,5'-tetramethylbenzidine, ethanol, and citric acid. The pH detection unit uses a general pH reagent.

[0305] In commercially available test strip 2, the materials for the nitrite detection unit include: sulfonamide and naphthylethylenediamine hydrochloride. The materials for the heavy metal detection unit include: diphenylcarbazide, hexadecyltrimethylamine bromide, polyvinyl alcohol, citric acid, acetone, and potassium dichromate. The materials for the water hardness detection unit include: sodium tetraborate, azo dye, and disodium ethylenediaminetetraacetate. The material for the residual chlorine detection unit includes: N,N-diethyl-p-phenylenediamine. The pH detection unit uses a general pH reagent.

[0306] Test case

[0307] The timer measures the color development time of the colorimetric detection unit 220. The color development time for the nitrite detection section in Examples 1 and Comparative Examples 1-2 is recorded as the first color development time. The color development time for the heavy metal detection section in Examples 1 and Comparative Examples 1-2 is recorded as the second color development time. The color development time for the water hardness detection section in Examples 1 and Comparative Examples 1-2 is recorded as the third color development time. The color development time for the residual chlorine detection unit in Examples 1 and Comparative Examples 1-2 is recorded as the fourth color development time. The color development time for the pH detection section in Examples 1 and Comparative Examples 1-2 is recorded as the fifth color development time.

[0308] The camera captures the colors of the colorimetric detection unit 220.

[0309] Table 1. Relationship between the examples, comparative examples, and color development time.

[0310]

[0311] Table 2. Volume of liquid to be tested in the examples and comparative examples.

[0312] Test strip type Volume of liquid to be measured Example 2 Test strips 100 microliters Comparative Example 3 Commercially available test strips 1 300 microliters Comparative Example 4 Commercially available test strips 2 500 microliters

[0313] Table 3. Material Detachment in Examples and Comparative Examples

[0314] Test strip type Has it fallen off? Example 3 Test strips no Comparative Example 5 Commercially available test strips 1 yes Comparative Example 6 Commercially available test strips 2 yes

[0315] Table 4. Relationship between the deterioration of the examples and comparative examples.

[0316] Test strip type Shelf life Example 4 Test strips 5 months Comparative Example 7 Commercially available test strips 1 2 months Comparative Example 8 Commercially available test strips 2 1 month

[0317] Table 1 shows that, compared to commercially available test strips 1 and 2, all different colorimetric detection layers of the test strips develop color within 5 seconds, and the color development time of different colorimetric detection sections 220 is less than 10 seconds. In commercially available test strip 1, the color development time for the nitrite detection section is 30 seconds, for the heavy metal detection section it is 120 seconds, for the water hardness detection section it is 600 seconds, for the residual chlorine detection section it is 15 seconds, and for the pH detection section it is instantaneous. The color development time intervals in commercially available test strip 1 are all greater than or equal to 10 seconds. In commercially available test strip 2, the color development time for the nitrite detection section is 60 seconds, for the heavy metal detection section it is 60 seconds, for the water hardness detection section it is 10 seconds, for the residual chlorine detection section it is 60 seconds, and for the pH detection section it is instantaneous. The color development time intervals in commercially available test strips are all greater than 15 seconds.

[0318] As shown in Table 2, the volume of test solution required for the test strip is 100 microliters, which is much smaller than the volumes required for commercially available test strips 1 and 2. When comparing the minimum volume of test solution required for color development between the test strip of this embodiment and commercially available test strips, the test solution is added dropwise to the test strip. After adding one drop of test solution, the test strip is observed to see if it changes color. If the test strip changes color, the volume of test solution added to the test strip is considered the minimum volume. Simultaneously, referring to Table 1, the addition time of the last drop of test solution to the test strip and the color change time interval of the test strip were recorded. Different colorimetric detection sections 220 of the test strip all developed color within 5 seconds, and the color development time of different colorimetric detection layers 200 of the test strip was less than 10 seconds. Compared to commercially available test strips, the color development time interval of the test strip provided in this embodiment is smaller.

[0319] Referring to Table 3, when the test strip provided in this embodiment is immersed in the liquid to be tested, the material of the colorimetric detection section 220 will not fall off, while both commercially available test strip 1 and commercially available test strip 2 will fall off.

[0320] Referring to Table 4, the shelf life of the test strips provided in this application embodiment is significantly longer than that of commercially available test strips 1 and 2. Specifically, the test strip is considered to have deteriorated when it no longer exhibits a colorimetric reaction. The shelf life is defined as the time from the completion of the test strip's preparation until the colorimetric reaction ceases.

[0321] Finally, it should be noted that other embodiments of the invention will readily occur to those skilled in the art upon consideration of the specification and practice of the invention disclosed herein. This invention is intended to cover any variations, uses, or adaptations of the invention that follow the general principles of the invention and include common knowledge or customary techniques in the art not disclosed herein, and is not limited to the precise structures described above and shown in the accompanying drawings, and various modifications and changes can be made without departing from its scope. The scope of the invention is limited only by the appended claims.

Claims

1. A test strip, characterized in that, include: Grassroots (100); A colorimetric detection layer (200) is disposed on the base layer (100). The colorimetric detection layer (200) includes a carrier layer (210) and at least two colorimetric detection units (220) disposed on the carrier layer (210). The colorimetric detection units (220) are disposed on the side of the carrier layer (210) close to the base layer (100). The color development time interval between at least two of the colorimetric detection units (220) is less than 10 seconds.

2. The test strip according to claim 1, characterized in that, It also includes a cover layer (300) disposed on the side of the colorimetric detection layer (200) away from the base layer (100).

3. The test strip according to claim 2, characterized in that, It also includes a seepage-proof layer (400), which is disposed between the base layer (100) and the colorimetric detection layer (200).

4. The test strip according to claim 3, characterized in that, It also includes a liquid-absorbing layer (500) disposed between the impermeable layer (400) and the colorimetric detection layer (200); the liquid-absorbing layer (500) has mounting holes through which the colorimetric detection layer (200) contacts the impermeable layer (400).

5. The test strip according to any one of claims 1-4, characterized in that, The colorimetric detection unit (220) includes a first colorimetric detection unit, which is used to detect water hardness. The materials of the first colorimetric detection unit include methyl thymol blue, masking agent, precipitant, and chelating agent.

6. The test strip according to claim 5, characterized in that, The masking agent includes sodium potassium tartrate; And / or, the precipitant includes sodium hydroxide; And / or, the chelating agent includes ethylenediaminetetraacetic acid.

7. The test strip according to claim 5, characterized in that, The colorimetric detection unit (220) includes a second colorimetric detection unit, which is used to detect the pH value of water. The materials of the second colorimetric detection unit include pH indicator and stabilizer.

8. The test strip according to claim 7, characterized in that, The pH indicator includes alizarin red; And / or, the stabilizer includes hexadecyltrimethylammonium bromide.

9. The test strip according to claim 7, characterized in that, The colorimetric detection unit (220) includes a third colorimetric detection unit, which is used to detect the chlorine content in water. The materials of the third colorimetric detection unit include a colorimetric reagent and a pH reagent.

10. The test strip according to claim 9, characterized in that, The colorimetric agent includes syringaldehyde azo; And / or, the pH reagent includes citrate-disodium hydrogen phosphate buffer.

11. The test strip according to claim 9, characterized in that, The colorimetric detection unit (220) includes a fourth colorimetric detection unit, which is used to detect heavy metals in water. The materials of the fourth colorimetric detection unit include a reducing agent, a colorimetric agent, an acid, and potassium iodide.

12. The test strip according to claim 11, characterized in that, The reducing agent includes ascorbic acid; And / or, the color developer includes Victoria Blue B; And / or, the acid includes hydrochloric acid.

13. The test strip according to claim 11, characterized in that, The colorimetric detection unit (220) includes a fifth colorimetric detection unit for detecting nitrite, and the materials of the fifth colorimetric detection unit include m-phenylenediamine hydrochloride and pH reagent.

14. The test strip according to claim 13, characterized in that, The pH reagent includes a citrate-disodium hydrogen phosphate buffer solution.

15. The test strip according to claim 6, characterized in that, The materials of the first colorimetric detection unit include sodium hydroxide, potassium sodium tartrate, methyl thymol blue, and ethylenediaminetetraacetic acid; the mass ratio of sodium hydroxide, potassium sodium tartrate, methyl thymol blue, and ethylenediaminetetraacetic acid is (10-40):(20-50):(10-20):(1-15).

16. The test strip according to claim 8, characterized in that, The materials of the second colorimetric detection unit include alizarin red and hexadecyltrimethylammonium bromide; the mass ratio of alizarin red to hexadecyltrimethylammonium bromide is (1-10):(1-16).

17. The test strip according to claim 14, characterized in that, The materials of the fourth colorimetric detection unit include ascorbic acid, potassium iodide, Victoria Blue B, and hydrochloric acid; the mass ratio of the ascorbic acid, potassium iodide, Victoria Blue B, and hydrochloric acid is (1-50):(300-700):(1-10):(10000-70000).

18. The test strip according to claim 4, characterized in that, The colorimetric detection unit (220) includes a liquid addition unit and a colorimetric unit. The liquid addition unit is disposed on the side of the colorimetric unit away from the carrier layer (210). The colorimetric unit and the liquid addition unit are connected, and the liquid addition unit is used to supply water quality to flow to the colorimetric unit.

19. The test strip according to claim 18, characterized in that, The liquid addition section has a liquid addition orifice; the colorimetric section has a colorimetric orifice, and the liquid addition orifice is larger than the colorimetric orifice.

20. The test strip according to claim 19, characterized in that, The size D1 of the liquid addition pore satisfies: 10μm≤D1≤15μm.

21. The test strip according to claim 18, characterized in that, The thickness P1 of the liquid addition section satisfies: 0.05mm≤P1≤0.15mm.

22. The test strip according to claim 19, characterized in that, The size of the colorimetric pore is D2, and D2 satisfies: 0.05μm≤D2≤0.15μm.

23. The test strip according to claim 18, characterized in that, The thickness of the colorimetric part is P2, and P2 satisfies: 1.5mm≤P2≤2.5mm.

24. The test strip according to claim 18, characterized in that, The liquid addition section includes a first liquid addition section and a plurality of second liquid addition sections, the plurality of second liquid addition sections being arranged at intervals along the outer periphery of the first liquid addition section; the number of colorimetric sections is plurality of, the plurality of colorimetric sections and the plurality of second liquid addition sections being arranged in a one-to-one correspondence.

25. The test strip according to claim 24, characterized in that, The first liquid filling section is circular in shape, and the second liquid filling section is also circular in shape.

26. The test strip according to claim 24, characterized in that, The diameter of the first liquid filling section is larger than the diameter of the second liquid filling section.

27. The test strip according to claim 24, characterized in that, The diameter M1 of the first liquid filling section satisfies: 0.5cm ≤ M1 ≤ 1.5cm; The diameter of the second liquid addition section is M2, and M2 satisfies: 2.5mm≤M2≤3.5mm.

28. The test strip according to claim 18, characterized in that, At least one of the following constraints must be met: The overlay (300) includes release paper; The carrier layer (210) includes silicone paper; The colorimetric unit includes glass fiber filter paper; The liquid addition section includes cotton fiber filter paper; The impermeable layer (400) includes silicone paper; The absorbent layer (500) includes glass fiber filter paper; The base layer (100) includes polyethylene terephthalate, polypropylene, and polyethylene.

29. The test strip according to claim 11, characterized in that, The color development time interval of at least three of the colorimetric detection units (220) is less than 10 seconds.

30. The test strip according to claim 11, characterized in that, The color development time interval of at least four of the colorimetric detection units (220) is less than 10 seconds.

31. The test strip according to claim 11, characterized in that, The color development time interval of the five colorimetric detection units (220) is less than 10 seconds.

32. The test strip according to any one of claims 1-4, characterized in that, The colorimetric detection layer (200) has a color development time of less than 15 seconds.

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