Hemoglobin and transferrin joint detection test strip and reagent plate

Abstract

The utility model provides a hemoglobin and transferrin joint detection test strip and a reagent plate, and belongs to the technical field of biological detection. The colloidal gold pad is coated with a conjugate of an anti-human hemoglobin monoclonal antibody and colloidal gold and a conjugate of an anti-human serum transferrin monoclonal antibody and colloidal gold; the first detection line T1 is coated with at least one of an anti-human hemoglobin specific antibody or an anti-human serum transferrin specific antibody; the hemoglobin and transferrin combined detection test strip is coated with at least one second detection line T2 line of an anti-human hemoglobin specific antibody or an anti-human serum transferrin specific antibody, and is coated with an anti-mouse IgG antibody quality control region C line; the detection of serum protein and transferrin can be rapidly realized at one time, the use amount of detection materials in actual combats is saved, and the kit conforms to the operation habits of public security actual combats and is more suitable for difficult bloodstain detection.

Description

Technical Field

[0001] This utility model belongs to the field of biological detection technology, specifically relating to a test strip and reagent plate for the combined detection of hemoglobin and transferrin. Background Technology

[0002] Bloodstains at crime scenes play a crucial role in identifying suspects. Fresh, obvious bloodstains can usually be identified visually. However, for samples that are difficult to distinguish, bloodstain testing is necessary to determine if it is indeed blood and, more specifically, human blood, serving as the basis for further DNA testing. Currently, the most commonly used method in police practice is the hemoglobin strip method. This method works by using anti-human hemoglobin antibodies to specifically bind to human hemoglobin antigens, thus detecting whether a sample is human blood. The hemoglobin test is often referred to as a "preliminary bloodstain test" in practice. However, the stability of hemoglobin is affected by various factors, including pH, ion concentration, temperature, oxygen content, and interactions with other biomolecules. Changes in these factors can cause alterations in the hemoglobin structure, leading to degradation, denaturation, or difficulty in leaching from old or contaminated bloodstains. This can result in false negatives and affect the interpretation of test results.

[0003] Serum transferrin, or transferrin for short, is a highly polymorphic genetic marker in human serum. Transferrin is more stable during storage, specifically binding to iron ions and transporting them in a cell-free manner, thus reducing the risk of oxidative stress and cell damage caused by free iron. Compared to hemoglobin, it is more stable under heat or other environmental conditions, maintaining its biological activity and function for a longer period. Compared to hemoglobin, transferrin is more stable under the influence of factors such as pH, temperature, ion concentration, oxygen content, and interactions with other biomolecules, and is less prone to denaturation and degradation. It can be used in confirmatory bloodstain tests.

[0004] In addition, at crime scenes, technicians often use chromogenic reagents such as blue light reagent, luminol reagent, and tetramethylbenzidine to develop potential bloodstains to discover bloodstains that are difficult to detect. These chromogenic reagents usually react with proteins to achieve a color development effect. These chromogenic reagents generally have a broad spectrum of reactions and a relatively high false positive rate. Further testing is needed to determine whether the discovered bloodstains are human blood and to identify individual bloodstains. Exploring more sensitive bloodstain experiments can compensate for the shortcomings of protein destruction in chromogenic experiments and provide support for determining whether the developed bloodstains are human blood and for subsequent bloodstain DNA testing.

[0005] Therefore, a test strip and reagent plate for the combined detection of hemoglobin and transferrin with a low false positive probability is needed to make up for the shortcomings of a single protein in the confirmatory testing of human bloodstains in difficult bloodstains in police practice. Utility Model Content

[0006] This invention addresses the problems of the prior art by providing a test strip and reagent plate for the combined detection of hemoglobin and transferrin.

[0007] To achieve the above objectives, the technical solution adopted in this application is as follows:

[0008] A test strip for the combined detection of hemoglobin and transferrin includes a sample application pad, a colloidal gold pad, a nitrocellulose membrane, an absorbent pad, and a carrier plate; the sample application pad, colloidal gold pad, nitrocellulose membrane, and absorbent pad are sequentially connected to the carrier plate via adhesive.

[0009] The colloidal gold pad is coated with a conjugate of anti-human hemoglobin monoclonal antibody and colloidal gold, as well as a conjugate of anti-human serum transferrin monoclonal antibody and colloidal gold; the nitrocellulose membrane is provided with a first detection line (T line), a second detection line (T line), and a quality control zone (C line) from left to right.

[0010] The first detection line T line is coated with at least one of an anti-human hemoglobin-specific antibody or an anti-human serum transferrin-specific antibody; the second detection line T line is coated with at least one of an anti-human hemoglobin-specific antibody or an anti-human serum transferrin-specific antibody; and the quality control area C line is coated with an anti-mouse IgG antibody.

[0011] Preferably, the sample pad and the colloidal gold pad have a 1mm to 2mm overlap at their respective ends; the colloidal gold pad and the nitrocellulose membrane have a 1mm to 2mm overlap at their respective ends; and the nitrocellulose membrane and the absorbent pad have a 1mm to 2mm overlap at their respective ends.

[0012] Preferably, the carrier board is a PVC board.

[0013] As a preferred embodiment, a hemoglobin and transferrin co-detection reagent strip includes the aforementioned hemoglobin and transferrin co-detection test strip and a plastic shell, wherein the plastic shell encloses the hemoglobin and transferrin co-detection test strip.

[0014] Preferably, the top surface of the plastic shell is provided with a sample application hole and an observation window, with a sample application pad below the sample application hole and a nitrocellulose membrane below the observation window.

[0015] Compared with the prior art, the advantages and positive effects of this utility model are as follows:

[0016] This invention relates to a hemoglobin and transferrin combined test strip and reagent plate. It features a colloidal gold pad coated with a conjugate of anti-human hemoglobin monoclonal antibody and colloidal gold, and a conjugate of anti-human serum transferrin monoclonal antibody and colloidal gold. The test strip and reagent plate also include a first detection line (T1) coated with at least one anti-human hemoglobin-specific antibody or anti-human serum transferrin-specific antibody, a second detection line (T2) coated with at least one anti-human hemoglobin-specific antibody or anti-human serum transferrin-specific antibody, and a control area (C) coated with anti-mouse IgG antibody. This invention overcomes the limitations of single-protein assays in confirmatory bloodstain testing and effectively supplements the confirmation of old, contaminated, and putrefied bloodstains. It allows for rapid, one-time detection of both serum proteins and transferrin, saving sample usage in practical applications, conforming to police operational practices, and is particularly suitable for examining complex bloodstains. Attached Figure Description

[0017] To more clearly illustrate the technical solutions in the embodiments of this utility model or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of this utility model. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0018] Figure 1 This is a schematic front view of the structure of the hemoglobin and transferrin combined test strip of this utility model;

[0019] Figure 2 These are schematic diagrams of the hemoglobin and transferrin combined test strip of this utility model, including a front view and a top view.

[0020] Figure 3 This is a schematic diagram of the structure of the hemoglobin and transferrin combined detection reagent plate of this utility model;

[0021] Figure 4 The image shows an example of a positive result determined by the test strip and reagent plate of this utility model.

[0022] Figure 5 Example diagram showing a negative result for the test strip and reagent plate of this utility model;

[0023] Figure 6 Example diagram showing the invalid results of the test strip and reagent plate of this utility model;

[0024] In the above figures, 1. Sample pad; 2. Colloidal gold pad; 3. Nitrocellulose membrane; 4. Absorbent pad; 5. Carrier plate; 6. First detection line T1; 7. Second detection line T2; 8. Quality control area C line; 9. Plastic shell. Detailed Implementation

[0025] To better understand the above-mentioned objectives, features, and advantages of this utility model, the present utility model will be further described below with reference to the accompanying drawings and embodiments. It should be noted that, unless otherwise specified, the embodiments and features described in these embodiments can be combined with each other.

[0026] Many specific details are set forth in the following description in order to provide a full understanding of the present invention. However, the present invention may also be implemented in other ways different from those described herein. Therefore, the present invention is not limited to the specific embodiments disclosed in the following specification.

[0027] Example 1, as Figures 1-6 As shown, a hemoglobin and transferrin combined test strip of this application includes a sample application pad 1, a colloidal gold pad 2, a nitrocellulose membrane 3, an absorbent pad 4, and a carrier plate 5; the sample application pad 1, the colloidal gold pad 2, the nitrocellulose membrane 3, and the absorbent pad 4 are sequentially connected to the carrier plate 5 by adhesive.

[0028] The colloidal gold pad 2 is coated with a conjugate of anti-human hemoglobin monoclonal antibody and colloidal gold, as well as a conjugate of anti-human serum transferrin monoclonal antibody and colloidal gold; the nitrocellulose membrane 3 is provided with a first detection line T1 line 6, a second detection line T2 line 7, and a quality control area C line 8 from left to right.

[0029] The first detection line T1 line 6 is coated with at least one of anti-human hemoglobin-specific antibody or anti-human serum transferrin-specific antibody; the second detection line T2 line 7 is coated with at least one of anti-human hemoglobin-specific antibody or anti-human serum transferrin-specific antibody; the quality control area C line 8 is coated with anti-mouse IgG antibody; in this embodiment, the first detection line T1 line 6 is coated with anti-human hemoglobin-specific antibody, and the second detection line T2 line 7 is coated with anti-human serum transferrin-specific antibody;

[0030] The sample application pad 1 and the colloidal gold pad 2 have a 1mm to 2mm overlap at their closest points; the colloidal gold pad 2 and the nitrocellulose membrane 3 have a 1mm to 2mm overlap at their closest points; the nitrocellulose membrane 3 and the absorbent pad 4 have a 1mm to 2mm overlap at their closest points.

[0031] The carrier board 5 is a PVC board;

[0032] Samples containing serum protein and transferrin were respectively dropped onto sample pad 1. The serum protein and transferrin samples bound to the anti-human hemoglobin monoclonal antibody-colloidal gold conjugate and the anti-human serum transferrin monoclonal antibody-colloidal gold conjugate on colloidal gold pad 2, respectively, forming colloidal gold antibody-antigen complexes. These complexes were then chromatographyd along the chromatographic direction to the detection zone, i.e., onto the nitrocellulose membrane 3. The complexes bound to the anti-human hemoglobin-specific antibody or the anti-human serum transferrin-specific antibody on the nitrocellulose membrane 3, respectively, forming the first detection line T1, the second detection line T2, and the third detection line T6. The color intensity of line 7, the first detection line T1, line 6, and the second detection line T2 is directly proportional to the content of serum protein and transferrin in the sample. The remaining colloidal gold antibody-antigen complex is chromatographically deposited into the control area and binds to the pre-coated anti-mouse IgG antibody, presenting control area line C 8. If the sample contains only serum protein, only the first detection line T1 6 will show color; if the sample contains only transferrin, only the second detection line T2 7 will show color; if the sample contains neither serum protein nor transferrin, neither the first detection line T1 6 nor the second detection line T2 7 will show color.

[0033] A hemoglobin and transferrin co-detection reagent strip includes the aforementioned hemoglobin and transferrin co-detection test strip and a plastic shell 9. The plastic shell 9 encloses the hemoglobin and transferrin co-detection test strip; the plastic shell serves both to fix the hemoglobin and transferrin co-detection test strip and to serve as an identification feature.

[0034] The top surface of the plastic shell 9 is provided with a sample application hole and an observation window, with a sample application pad 1 below the sample application hole and a nitrocellulose membrane 3 below the observation window.

[0035] When using the reagent plate of this application for testing, i.e., when performing a confirmatory test for human bloodstains, the biological sample to be tested is dropped onto the sample pad 1 through the sample application hole. After standing for a few minutes, the sample is observed through the observation window along the first detection line T1 (6), the second detection line T2 (7), and the color development of the control area C line 8. Figure 4 - Figure 6 The example diagram in the image is used to determine whether hemoglobin and transferrin are present in biological samples.

[0036] 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 other way. Any person skilled in the art may make changes or modifications to the above-disclosed technical content to create equivalent embodiments for application in other fields. However, any simple modifications, equivalent changes, and modifications made to the above embodiments based on the technical essence of the present utility model without departing from the technical solution of the present utility model shall still fall within the protection scope of the technical solution of the present utility model.

Claims

1. A test strip for the combined detection of hemoglobin and transferrin, characterized in that, It includes a sample application pad (1), a colloidal gold pad (2), a nitrocellulose membrane (3), an absorbent pad (4), and a carrier plate (5); the sample application pad (1), the colloidal gold pad (2), the nitrocellulose membrane (3), and the absorbent pad (4) are sequentially connected on the carrier plate (5) by adhesive tape. The colloidal gold pad (2) is coated with a conjugate of anti-human hemoglobin monoclonal antibody and colloidal gold, and a conjugate of anti-human serum transferrin monoclonal antibody and colloidal gold; the nitrocellulose membrane (3) is provided with a first detection line T1 line (6), a second detection line T2 line (7), and a quality control area C line (8) from left to right. The first detection line T1 (6) is coated with anti-human hemoglobin specific antibody, while the second detection line T2 (7) is coated with anti-human serum transferrin specific antibody; or the first detection line T1 (6) is coated with anti-human serum transferrin specific antibody, while the second detection line T2 (7) is coated with anti-human hemoglobin specific antibody; the quality control area C line (8) is coated with anti-mouse IgG antibody.

2. The hemoglobin and transferrin combined detection test strip according to claim 1, characterized in that, The sample application pad (1) and the colloidal gold pad (2) have a 1mm to 2mm overlap at their respective ends; the colloidal gold pad (2) and the nitrocellulose membrane (3) have a 1mm to 2mm overlap at their respective ends; the nitrocellulose membrane (3) and the absorbent pad (4) have a 1mm to 2mm overlap at their respective ends.

3. The hemoglobin and transferrin combined detection test strip according to claim 1, characterized in that, The carrier board (5) is a PVC board.

4. A reagent strip for the combined detection of hemoglobin and transferrin, characterized in that, It includes the hemoglobin and transferrin combined test strip as described in any one of claims 1-3 and a plastic shell (9), wherein the plastic shell (9) encloses the hemoglobin and transferrin combined test strip.

5. The hemoglobin and transferrin combined detection reagent strip according to claim 4, characterized in that, The top surface of the plastic shell (9) is provided with a sample application hole and an observation window, with a sample application pad (1) below the sample application hole and a nitrocellulose membrane (3) below the observation window.

Images