Hybridoma cell strain secreting anti-captopril monoclonal antibody and application thereof

Abstract

The invention relates to a hybridoma cell strain secreting an anti-captopril monoclonal antibody and application of the hybridoma cell strain, and belongs to the technical field of drug safety immunoassay. The hybridoma cell strain secreting the anti-monoclonal antibody is preserved in China General Microbiological Culture Collection Center (CGMCC) on the year, the preservation number is CGMCC No.46502, the preservation address is No.3, Yard 1, Beichen West Road, Chaoyang District, Beijing, and the hybridoma cell strain is classified and named as a monoclonal cell strain. The captopril monoclonal antibody cell strain obtained by the invention can be used for drug quality detection and captopril residue detection in a biological sample, has better detection sensitivity (IC50 value is 3.433 ng / mL) and specificity (the cross-over rate for related structural analogues is less than 1%) to captopril, and can realize detection of captopril in drugs and biological samples; and an efficient immunodetection tool is provided for clinical medication detection and drug quality control, the clinical medication safety and effectiveness are guaranteed in an assisted manner, and the kit has a definite practical application value.

Description

Technical Field

[0001] This invention relates to the field of drug safety immunoassay technology, and in particular to a hybridoma cell line that secretes anti-captopril monoclonal antibody and its application. Background Technology

[0002] Captopril is an angiotensin-converting enzyme inhibitor (ACEI) primarily used to treat cardiovascular and related diseases such as hypertension, congestive heart failure, and diabetic nephropathy. Its mechanism of action involves inhibiting the activity of angiotensin-converting enzyme, thereby dilating blood vessels, lowering blood pressure, reducing cardiac workload, and protecting kidney function.

[0003] However, the safety of captopril remains controversial. Studies have shown that long-term excessive intake of captopril may pose potential health risks, such as disrupting the endocrine system, increasing the likelihood of certain tumors, and having a more significant impact on the health of children and sensitive populations. Furthermore, some companies have illegally exceeded permitted dosages in pursuit of better product preservation, leading to frequent issues of excessive captopril residues in food and pharmaceuticals.

[0004] In clinical practice, accurately determining the concentration changes of captopril in the body is crucial. Currently, the main methods for captopril content determination include ultra-high performance liquid chromatography-mass spectrometry (UPLC-MS / MS), gas chromatography-tandem mass spectrometry (GC-MS / MS), and high performance liquid chromatography (HPLC-UV). However, these methods have significant limitations, requiring specialized equipment and operators, and are relatively expensive, making them difficult to meet the needs of real-time clinical monitoring and batch sample testing.

[0005] Enzyme-linked immunosorbent assay (ELISA) technology offers a new solution for captopril detection. With its high sensitivity and fast detection speed, this technology can detect trace amounts of captopril in biological samples such as blood and urine. Furthermore, its relatively simple operation greatly improves the flexibility and timeliness of testing. The application of this technology is expected to solve the problems of traditional detection methods, promote the development of clinical captopril testing technology, and provide more efficient technical support for precision medication guidance and ensuring patient medication safety. Summary of the Invention

[0006] To address the shortcomings of existing instruments in detecting captopril, this invention provides a hybridoma cell line that secretes an anti-captopril monoclonal antibody and its application. The antibody secreted by this cell line exhibits high detection sensitivity against captopril and can be used to establish an immunological detection method for captopril.

[0007] This invention is achieved through the following technical solution:

[0008] The first objective of this invention is to provide a hybridoma cell line that secretes a monoclonal antibody against captopril. This hybridoma cell line was deposited on April 17, 2025, at the China General Microbiological Culture Collection Center (CGMCC) with accession number CGMCC No. 46502. The deposit address is No. 3, Courtyard 1, Beichen West Road, Chaoyang District, Beijing, and it is classified as a monoclonal cell line.

[0009] In one embodiment of the invention, the hybridoma cell line is obtained by immunizing mice with captopril complete antigen.

[0010] In one embodiment of the present invention, the captopril complete antigen is obtained by conjugating the captopril hapten with a carrier protein.

[0011] In one embodiment of the present invention, the immunogenic vector is selected from keyhole hemocyanin and / or chicken ovalbumin.

[0012] In one embodiment of the present invention, the structural formula of the captopril hapten is:

[0013]

[0014] A second objective of this invention is to provide a captopril monoclonal antibody produced by the hybridoma cell line described above.

[0015] In one embodiment of the present invention, sterile paraffin oil is injected into the peritoneum of an immunized animal, followed by a hybridoma cell line with accession number CGMCC No. 46502. Ascites fluid is collected after injection, purified, and the captopril monoclonal antibody is obtained and cryopreserved.

[0016] A third objective of this invention is to provide a composition for detecting captopril, the composition comprising the hybridoma cell line and / or the captopril monoclonal antibody.

[0017] A fourth objective of this invention is to provide a kit for detecting captopril, the kit comprising one or more of the hybridoma cell line, the captopril monoclonal antibody, and the composition described herein.

[0018] In one embodiment of the present invention, the kit is selected from enzyme-linked immunosorbent assay (ELISA) kits, fluorescence immunoassay kits, or chemiluminescent immunoassay kits.

[0019] A fifth objective of this invention is to provide a test strip for detecting captopril, the test strip comprising one or more of the aforementioned hybridoma cell line, the aforementioned captopril monoclonal antibody, and the aforementioned composition.

[0020] A sixth objective of this invention is to provide the application of the hybridoma cell line, the captopril monoclonal antibody, the composition, the kit, or the test strip in the detection of captopril, particularly in the analysis and detection of captopril residues in pharmaceuticals and biological samples.

[0021] The seventh objective of this invention is to provide a method for preparing the hybridoma cell line secreting anti-captopril monoclonal antibody, comprising the following steps:

[0022] S1. Preparation of captopril hapten;

[0023] S2. Prepare captopril immunogen and captopril-coated antigen, and prepare the obtained captopril immunogen into Freund's complete adjuvant containing antigen and Freund's incomplete adjuvant containing antigen.

[0024] S3. Perform initial immunization, booster immunization, and sprint immunization on immunized animals. The initial immunization uses Freund's complete adjuvant containing antigen as described in S2, the booster immunization uses Freund's incomplete adjuvant containing antigen as described in S2, and the sprint immunization uses captopril immunogen as described in S2.

[0025] S4. Take spleen cells and myeloma cells from the immunized animals after the sprint immunization in S3 and perform cell fusion to obtain the hybridoma cell line of the anti-captopril monoclonal antibody.

[0026] In one embodiment of the present invention, step S1, the preparation method of the captopril hapten includes the following steps: dissolving eugenol and ethyl bromohexanoate in a solvent, adding potassium carbonate and heating in a water bath to remove the organic solvent, washing, and drying to obtain a yellow oily substance. Subsequently, dissolving the yellow oily substance in methanol, adding sodium hydroxide solution, heating in a water bath again, washing, and recrystallizing to obtain the captopril hapten.

[0027] In one embodiment of the present invention, step S2, the method for preparing the captopril immunogen and the coating antigen includes the following steps: using the carbodiimide method, the captopril hapten is conjugated with the carrier proteins KLH and OVA to prepare the immunogen captopril-KLH and the coating antigen captopril-OVA, respectively.

[0028] In one embodiment of the present invention, the preparation method of the captopril immunogen and coating antigen specifically includes the following steps: dissolving the captopril hapten in DMF, adding N-hydroxysuccinimide and 1-ethylcarbodiimide hydrochloride, and stirring at room temperature to react, which is called solution A; weighing different carrier proteins and adding them to a buffer solution, which is called solution B; slowly adding solution A dropwise to solution B while stirring, and reacting at room temperature to obtain a mixture; dialysis to obtain the captopril immunogen and coating antigen.

[0029] In one embodiment of the present invention, in step S2, the antigen-containing Freund's complete adjuvant is an emulsion of equal volume of Freund's complete adjuvant and captopril immunogen.

[0030] In one embodiment of the present invention, in S2, the antigen-containing Freund's incomplete adjuvant is an emulsion of equal volume of Freund's incomplete adjuvant and captopril immunogen.

[0031] In one embodiment of the present invention, in step S3, the entire immunization process includes one initial immunization, three to five booster immunizations, and one sprint immunization.

[0032] In one embodiment of the present invention, in step S3, the interval between the first immunization and the booster immunization is 28-31 days, the interval between booster immunizations is 20-22 days, and the interval between booster immunization and the sprint immunization is 18-21 days.

[0033] In one embodiment of the present invention, in step S3, the initial immunization and booster immunization are administered to the immunized animal via subcutaneous injection on the back; the sprint immunization is administered to the immunized animal via intraperitoneal injection.

[0034] In one embodiment of the present invention, in step S3, blood is collected from the immunized animals during the booster immunization process, and the serum titer and inhibition rate are detected by indirect competitive enzyme-linked immunosorbent assay (icELISA) to screen out immunized animals with high titer and good inhibition.

[0035] In one embodiment of the present invention, in step S3, blood is collected on days 6-8 after the completion of the booster immunization process.

[0036] In one embodiment of the present invention, in step S4, cell fusion involves culturing the fused cells in RPMI-1640 selection medium containing fetal bovine serum and 50×HAT, detecting positive cell wells using indirect ELISA, and further determining the inhibitory effect of positive cell wells using indirect competitive ELISA. The positive cell wells with the best inhibition are then subcloned using limiting dilution to obtain hybridoma cell lines.

[0037] In one embodiment of the present invention, the number of subcloning operations is 2-3.

[0038] In one embodiment of the present invention, in step S4, the cell fusion is performed by the polyethylene glycol (PEG 1500) method.

[0039] In one embodiment of the present invention, in step S4, the cell fusion is performed 3 days after the end of the sprint immunization.

[0040] The technical solution of the present invention has the following advantages compared with the prior art:

[0041] The monoclonal antibody secreted by the tumor cell line provided by this invention exhibits good specificity (cross-linking rate with related structural analogs less than 1%) and detection sensitivity (IC50) for captopril. 50 With values ​​of 3.433 ng / mL, this monoclonal antibody can detect captopril content in biological samples. Based on the above characteristics, this monoclonal antibody can achieve highly accurate detection of captopril content in drugs and biological samples, providing an efficient immunoassay tool for clinical drug testing and drug quality control, helping to ensure the safety and effectiveness of clinical drug use, and has clear practical application value.

[0042] Preservation of biological materials:

[0043] A hybridoma cell line, LXP, secreting a monoclonal antibody against captopril, has been deposited at the China General Microbiological Culture Collection Center (CGMCC), located at No. 3, Courtyard 1, Beichen West Road, Chaoyang District, Beijing, Institute of Microbiology, Chinese Academy of Sciences. It has been classified as a monoclonal cell line, deposited on April 17, 2025, with accession number CGMCC No. 46502. Attached Figure Description

[0044] To make the content of this invention easier to understand, the invention will be further described in detail below with reference to specific embodiments and accompanying drawings, wherein:

[0045] Figure 1 This is a standard curve showing the inhibition of captopril by the captopril monoclonal antibody of this invention. Detailed Implementation

[0046] The present invention will be further described below with reference to the accompanying drawings and specific embodiments, so that those skilled in the art can better understand and implement the present invention. However, the embodiments described are not intended to limit the present invention.

[0047] Unless otherwise specified, the experimental methods used in the following examples are conventional methods, and the materials and reagents used are commercially available.

[0048] (1) The culture media involved in the following examples are as follows:

[0049] RPMI-1640 medium (mg / L): L-arginine 290, L-asparagine 50, L-aspartic acid 20, L-cysteine ​​dihydrochloride 65.15, L-glutamic acid 20, glycine 10, L-histidine 15, L-hydroxyproline 20, L-isoleucine 50, L-leucine 50, L-lysine hydrochloride 40, L-methionine 15, L-phenylalanine 15, L-proline 20, L-serine 30, L-threonine 20, L-tryptophan 5, L-tyrosine 23. 19. L-Valine 20. Para-aminobenzoic acid 1. Calcium nitrate 100. Anhydrous magnesium sulfate 48.84. Anhydrous sodium dihydrogen phosphate 676.13. Potassium chloride 400. Sodium chloride 6000. Glucose 2000. Reduced glutathione 1. Phenol red 5. L-glutamine 300. Biotin 0.2. D-calcium pantothenate 0.25. Folic acid 1. I-inositol 35. Nicotinamide 1. Choline chloride 3. Pyridoxine hydrochloride 1. Riboflavin 0.2. Thiamine hydrochloride 1. Vitamin B12 0.005. Sodium bicarbonate 2000.

[0050] (2) The reagents involved in the following examples are as follows:

[0051] Carbonate buffer (CBS): Weigh 1.59 g of Na2CO3 and 2.93 g of NaHCO3, dissolve them separately in a small amount of double-distilled water and mix them together. Add double-distilled water to about 800 mL and mix well. Adjust the pH to 9.6 and add double-distilled water to a final volume of 1000 mL. Store at 4°C for later use.

[0052] Phosphate-buffered saline (PBS): 8.00g NaCl, 0.2g KCl, 0.2g KH2PO4, 2.9g Na2HPO4·12H2O, dissolved in 800mL pure water, pH adjusted to 7.2-7.4 with NaOH or HCl, and then brought to a final volume of 1000mL with ultrapure water.

[0053] Washing buffer (PBST): Add 0.5 mL of Tween-20 to 1000 mL of 0.01 mol / L pH 7.4 PBS solution;

[0054] Antibody diluent: a washing solution containing 0.1% gelatin;

[0055] TMB colorimetric solution: Solution A: 18.43g Na2HPO4·12H2O, 9.33g citric acid, diluted to 1000mL with pure water; Solution B: 60mg TMB dissolved in 100mL ethylene glycol. Mix solutions A and B in a volume ratio of 5:1 to obtain the TMB colorimetric solution. Mix fresh before use.

[0056] (3) The detection methods involved in the following embodiments are as follows:

[0057] Captopril inhibition rate assay: The optimal antigen and antibody concentrations for icELISA were selected using a checkerboard assay. The antigen was diluted to 1 μg / mL, 0.3 μg / mL, 0.1 μg / mL, and 0.03 μg / mL with carbonate buffer (CBS), and the antibody was diluted to 1 μg / mL, 0.3 μg / mL, 0.1 μg / mL, and 0.03 μg / mL with antibody dilution buffer. After selecting the optimal operating point, captopril standards were diluted to concentrations of 100 ng / mL, 33.33 ng / mL, 11.11 ng / mL, 3.70 ng / mL, 1.23 ng / mL, 0.41 ng / mL, and 0.14 ng / mL, following the icELISA procedure. Finally, an inhibition curve of captopril was obtained using Origin 2024, and the IC50 was calculated. 50 .

[0058] Example:

[0059] This embodiment provides a method for preparing a hybridoma cell line that secretes an anti-captopril monoclonal antibody, specifically including the following steps:

[0060] (1) Preparation of hapten

[0061] 100 mg of eugenol was dissolved in a solvent and stirred until homogeneous. Then, 212.3 mg of EDC was added, and the mixture was stirred at 80 °C for 1 h. After cooling, 228.3 mg of ethyl aminohexanoate hydrochloride, which had been dissolved in the solvent, was added, and the mixture was reacted at room temperature for 24 h. The mixture was then washed with deionized water and dried to obtain a yellow oily substance. Subsequently, this yellow oily substance was added to methanol and 1 M NaOH and heated in a water bath at 70 °C for 43 h to remove the organic solvent. The mixture was washed three times with deionized water and 1 M HCl, and recrystallized with ethanol to obtain a white solid, namely the captopril hapten Cap-COOH.

[0062] (2) Preparation of immunogens

[0063] Weigh 7.8 mg of captopril hapten Cap-COOH and dissolve it in 300 μL of DMF. Add 8.9 mg of N-hydroxysuccinimide and react for 15 min with stirring at room temperature. Then add 13.2 mg of 1-ethylcarbodiimide hydrochloride and react at room temperature for 6 h. The resulting mixture is called solution A. Then weigh 6 mg of keyhole hemocyanin (KLH) and dissolve it in 2 mL of carbonate buffer, which is called solution B. Slowly add solution A to solution B and react at room temperature with stirring for 24 h. Dialyze the mixture with 0.01 mol / L phosphate-buffered saline (PBS) for 3 days to obtain the conjugate Cap-COOH-KLH, which is stored at -20°C for later use.

[0064] (3) Preparation of coating antigen

[0065] Weigh 5.9 mg of captopril hapten Cap-COOH and dissolve it in 300 μL of DMF. Add 6.2 mg of N-hydroxysuccinimide under stirring at room temperature and react for 15 min. Then add 8.9 mg of 1-ethylcarbodiimide hydrochloride and react at room temperature for 6 h. The resulting mixture is called solution A. Then weigh 10 mg of ovalbumin (OVA) and dissolve it in 2 mL of carbonate buffer, which is called solution B. Slowly add solution A to solution B and react at room temperature for 24 h with stirring. Dialyze the mixture with 0.01 mol / L phosphate-buffered saline (PBS) for 3 days to obtain the conjugate Cap-COOH-OVA, which is stored at -20℃ for later use.

[0066] (4) Immunization of mice: Healthy BALB / c mice aged 6-8 weeks were selected for immunization. Captopril immunogen was emulsified with an equal volume of Freund's adjuvant and administered subcutaneously via the back of the mouse. The first immunization used complete Freund's adjuvant, and subsequent immunizations used incomplete Freund's adjuvant. The interval between the first and second booster immunizations was 28 days, and the interval between multiple booster immunizations was 21 days. Seven days after the third immunization, blood was collected (5 μL of blood from tail amputation + 995 μL of antibody diluent = antiserum). The serum titer and inhibition were measured using icELISA. Mice with high titers and good inhibition were selected for a sprint immunization 21 days after the fifth immunization, administered via intraperitoneal injection. The sprint immunization dose was halved and contained no adjuvant.

[0067] (5) Cell fusion: Three days after the sprint immunization, cell fusion was performed using the conventional PEG (polyethylene glycol, molecular weight 1500) method. The specific steps are as follows:

[0068] a. After euthanizing the mice by enucleation and cervical dislocation-assisted carbon dioxide euthanasia, immediately disinfect the mice in 75% alcohol for about 5 minutes. Under aseptic conditions, remove the spleens of the mice, grind them moderately with the rubber tip of a syringe and pass them through a 200-mesh cell sieve to obtain a spleen cell suspension. Collect the suspension and centrifuge it (1200 rpm, 8 minutes). Wash the spleen cells three times with RPMI-1640 medium. After the last centrifugation, dilute the spleen cells to a certain volume, count them, and set them aside for later use.

[0069] b. Collection of murine myeloma SP2 / 0 cells: 7-10 days before fusion, SP2 / 0 tumor cells were cultured in RPMI-1640 medium containing 10% FBS (fetal bovine serum) in a 5% CO2 incubator. The required number of SP2 / 0 tumor cells before fusion was (1-4) × 10⁻⁶. 7 To ensure that SP2 / 0 tumor cells are in the logarithmic growth phase before fusion, tumor cells are collected and suspended in RPMI-1640 basal culture medium for cell counting.

[0070] c. Fusion process (7 min). At min 1, add 1 mL of PEG 1500 dropwise to the cells, gradually increasing the speed. At min 2, allow to stand. At min 3 and min 4, add 1 mL of RPMI-1640 medium dropwise over 1 min. At min 5 and min 6, add 2 mL of RPMI-1640 medium dropwise over 1 min. At min 7, add 1 mL of RPMI-1640 medium dropwise every 10 seconds. Then incubate at 37°C for 5-8 min. Centrifuge (800 rpm, 8 min), discard the supernatant, and resuspend in RPMI-1640 selection medium (containing 20% ​​fetal bovine serum and 2% 50×HAT RPMI-1640 medium). Add 200 μL / well to a 96-well cell plate and incubate at 37°C in a 5% CO2 incubator.

[0071] (6) Cell screening and cell line establishment: On day 3 of cell fusion, the fused cells were partially replaced with RPMI-1640 screening medium (RPMI-1640 medium containing 20% ​​fetal bovine serum and 2% 50×HAT). On day 5, the medium was completely replaced with RPMI-1640 transition medium (RPMI-1640 medium containing 20% ​​fetal bovine serum and 1% 100×HT). On day 7, the cell supernatant was collected for screening. The screening consisted of two steps: first, positive cell wells were selected using icELISA; second, captopril was used as a standard, and the inhibitory effect on positive cells was determined using icELISA. Cell wells that showed good inhibition of captopril standard were selected, and subcloning was performed using the limiting dilution method. The same method was used for detection, repeated three times, to obtain cell lines.

[0072] Test example:

[0073] (1) Preparation and identification of monoclonal antibodies

[0074] BALB / c mice aged 6-8 weeks were injected intraperitoneally with 0.5 mL of sterile paraffin oil; 7 days later, each mouse was injected intraperitoneally with 1×10 6 Hybridoma cells were used, and ascites fluid was collected starting on day 7. The ascites fluid was purified using the caprylic acid-ammonium sulfate method. Under slightly acidic conditions, caprylic acid precipitates other proteins in the ascites fluid besides IgG immunoglobulins. The precipitate was then discarded by centrifugation. IgG-type monoclonal antibodies were then precipitated with an equal volume of saturated ammonium sulfate solution, centrifuged, and the supernatant was discarded. The precipitate was dissolved in 0.01M PBS solution (pH 7.4), dialyzed to desalt, and finally the purified monoclonal antibodies were stored at -20°C.

[0075] The IC50 of the monoclonal antibody against captopril was determined using an indirect competitive ELISA method. 50 The concentration was 3.433 ng / mL, and its IC50 for analogues was verified. 50and cross-reactivity rate, with a cross-reactivity of less than 1% for analogues, where cross-reactivity = (IC of captopril) 50 ICs of similar types 50 The cross-reactivity ratio (×100%) indicates that this antibody has high sensitivity and specificity to captopril, as shown in Table 1.

[0076] Table 1. IC50 values ​​of monoclonal antibodies against captopril, its functional analogue benazepril, fosinopril, and lanoxetine. 50 and cross-reactivity rate

[0077] Table 1

[0078] <![CDATA[IC 50 (ng / mL)]]> Cross-reactivity rate (%) Captopril 3.433 100 Benapuri >34.3 <1 Forsimplin >34.3 <1 Lanopelli >34.3 <1

[0079] (2) Antibody application

[0080] The monoclonal antibody prepared from hybridoma cell lines via in vivo ascites fluid was used in a captopril spiking and recovery assay. The specific steps are as follows:

[0081] a. Coating: The original captopril-OVA was serially diluted with 0.05M pH 9.6 carbonate buffer starting from 1 μg / mL, 100 μL / well, and reacted at 37℃ for 2 h;

[0082] b. Washing: Pour off the solution in the plate and wash with washing solution 3 times, 3 minutes each time;

[0083] c. Sealing: After patting dry, add 200 μL / well sealing solution and react at 37℃ for 2 h. Wash and dry for later use.

[0084] d. Sample addition: Serially dilute the antiserum (antiserum obtained by diluting mouse tail blood with antibody diluent) starting from 1:1000 and add it to each well of the coated sample at 100 μL / well. Incubate at 37°C for 30 min. After thorough washing, add 1:3000 diluted HRP-goat anti-mouse IgG at 100 μL / well and incubate at 37°C for 30 min.

[0085] e. Color development: Remove the microplate, wash it thoroughly, add 100 μL of TMB color development solution to each well, and react at 37°C in the dark for 15 min.

[0086] f. Termination and Measurement: Add 50 μL of stop solution to each well to terminate the reaction, and then measure the OD of each well using a microplate reader. 450 value.

[0087] The standard curve of captopril inhibition by captopril monoclonal antibody is as follows: Figure 1 As shown, the IC50 of the monoclonal antibody against captopril was determined using icELISA. 50The concentration was 3.433 ng / mL, indicating good sensitivity to captopril, making it suitable for captopril immunoassay.

[0088] Regarding the recovery rate, the biological samples were analyzed by liquid chromatography-tandem mass spectrometry (LC-MS / MS). LC-MS / MS analysis showed no detectable captopril residues in either sample. Therefore, in this implementation case, the recovery rate was determined by adding captopril. As shown in Table 2, the results of the indirect competitive ELISA were similar to those of the LC-MS / MS results, indicating that the method for detecting captopril based on captopril monoclonal antibodies is relatively accurate and can be used for immunoassay detection of captopril residues in biological samples such as blood and urine.

[0089] Table 2 shows the recovery rates of captopril in blood and urine using monoclonal antibodies in indirect competitive ELISA and LC-MS / MS.

[0090]

[0091] Obviously, the above embodiments are merely illustrative examples for clear explanation and are not intended to limit the implementation. Those skilled in the art will recognize that other variations or modifications can be made based on the above description. It is neither necessary nor possible to exhaustively list all possible implementations here. However, obvious variations or modifications derived therefrom are still within the scope of protection of this invention.

Claims

1. A hybridoma cell line that secretes an anti-captopril monoclonal antibody, characterized in that, The hybridoma cell line was deposited on April 17, 2025, at the China General Microbiological Culture Collection Center (CGMCC) with accession number CGMCC No. 46502. The deposit address is No. 3, Courtyard 1, Beichen West Road, Chaoyang District, Beijing, and it is classified as a monoclonal cell line.

2. The hybridoma cell line according to claim 1, characterized in that, The hybridoma cell line was obtained by immunizing mice with captopril complete antigen.

3. The hybridoma cell line according to claim 2, characterized in that, The captopril complete antigen is obtained by conjugating the captopril hapten with a carrier protein.

4. The hybridoma cell line according to claim 3, characterized in that, The structural formula of the captopril hapten is:

5. Captopril monoclonal antibody, characterized in that, Produced by the hybridoma cell line according to any one of claims 1-4.

6. A composition for detecting captopril, characterized in that, The composition comprises the hybridoma cell line of any one of claims 1-4 and / or the captopril monoclonal antibody of claim 5.

7. A kit for detecting captopril, characterized in that, The kit comprises one or more of the hybridoma cell lines of any one of claims 1-4, the captopril monoclonal antibody of claim 5, and the composition of claim 6.

8. The reagent kit according to claim 7, characterized in that, The kit is selected from enzyme-linked immunosorbent assay (ELISA) kits, fluorescence immunoassay kits, or chemiluminescence immunoassay kits.

9. A test strip for detecting captopril, characterized in that, The test strip comprises one or more of the hybridoma cell lines of any one of claims 1-4, the captopril monoclonal antibody of claim 5, and the composition of claim 6.

10. The use of the hybridoma cell line of any one of claims 1-4, the captopril monoclonal antibody of claim 5, the composition of claim 6, the kit of claim 7 or 8, or the test strip of claim 9 in the detection of captopril.

Images