44 results about "Coating antigen" patented technology

The invention provides an ELISA (Enzyme Linked Immunosorbent Assay) kit for detecting an anti-MDA5 antibody and a preparation method of the ELISA kit. According to the kit, full-length human MDA5 protein (1025 amino acids) expressed by a cell-free protein expression system under the low-temperature condition of 22 DEG C is adopted as a coating antigen, and a disulfide bond enhancer E6820 is added into the system to promote correct folding of the protein. The kit comprises a microwell plate coated with a full-length MDA5 antigen, an enzyme-labeled anti-human IgG secondary antibody, a standard substance with the concentration range of 1-243 ng / mL, a chromogenic substrate and an optimized confining liquid system. The invention solves the problem of insufficient sensitivity caused by the use of fragment antigens in the prior art, and can be used for early diagnosis and illness monitoring of dermatomyositis-related interstitial lung diseases.

The application relates to a sensor for synchronously detecting enniatin and roquefortine based on a double-potential electrochemiluminescence immunoassay technology as well as a preparation method and a detection method thereof. The sensor comprises a base electrode, a sensing interface composed of a nanocomposite is modified on the surface of the base electrode, mixed coated antigens including ENNs-BSA and AOH-BSA fixed on the sensing interface, mixed probes including a cathode probe and an anode probe, the cathode probe is Zr-Por-MOF-ENNs Ab which is obtained by marking ENNs antibodies with a porphyrin zirconium metal organic framework, the anode probe is Ce-In-MOF@ABEI-AOH Ab which is obtained by marking AOH antibodies with ABEI loaded on a cerium-doped indium metal organic framework, and a detection solution containing a single co-reactant potassium persulfate. The application can realize one-time sample adding, double-potential scanning and synchronous quantification for two kinds of mycotoxins of enniatin and roquefortine.

This invention discloses a quantitative test strip for HBV PreS1 antibody based on the AIE molecule, its preparation method, and its applications, relating to the fields of molecular biology, immunology, and biodetection technology. The test strip includes a sample pad, a labeling pad, a nitrocellulose membrane (NC membrane), an absorbent pad, and a base plate. The NC membrane detection line is coated with HBV PreS1 antigen to capture PreS1 antibodies in the sample. The labeling pad contains an immobilized Anti-Human IgG antibody conjugated to the AIE molecule, which binds to the PreS1 antibodies in the sample to form an immune complex. The test strip of this invention enables rapid detection of PreS1 antibodies and achieves enhanced fluorescence in the detection results. Combined with a fluorescence reader or fluorescence card reader, the detection results can be digitally and quantitatively analyzed. It is simple to operate, rapid in detection, and significantly improves detection sensitivity and enables quantitative analysis.

The application relates to a detection method of anti-preS1 antibody, an anti-preS1 antibody detection kit and application, the application carries out multi-sequence comparison and conservation analysis on preS1 sequences of different genotypes (A, B, C, D and CD mixed type) of HBV, takes type A (AB697487.1), type C (FJ032351.1) and type D (LC519808.1) as reference sequences, based on the sequence consistency standard of 85% of full length and 90% of the key region of functional antibody binding, a highly conservative preS1 full-length antigen sequence is systematically screened out in natural variation, the sequence can cover antigen variation of A-D type HBV, and the sequence is taken as a coating antigen to establish an indirect ELISA detection system, a good linear relationship is presented in the range of 4.88-625 ng / mL, and the Cut-off value is 33.6 ng / mL; clinical verification shows that the method can effectively distinguish chronic hepatitis B patients from healthy control groups, compared with detection methods based on partial fragments or overlapping short fragments, the false negative rate can be significantly reduced, and the method is suitable for HBV infection immune state evaluation, anti-virus curative effect monitoring and prognosis analysis.

The invention provides a linear epitope of an African swine fever virus CP312R protein. The amino acid sequence of the linear epitope is SEQ ID NO: 1 or SEQ ID NO: 2. The antigen epitope polypeptide provided by the invention has good antigen specificity and immunoreactivity. The polypeptide can be efficiently combined with an African swine fever virus specific antibody, background interference is low, cross reaction is small, and detection sensitivity and accuracy are remarkably improved. By using the polypeptide as a coating antigen in immunodetection methods such as ELISA or colloidal gold immunochromatography, rapid and accurate detection of ASFV infection can be realized, and the detection result is stable and reliable. Compared with a traditional whole virus antigen or a crude extract antigen, the epitope polypeptide has the advantages of being simple and convenient to prepare, small in batch difference, high in safety and the like, and is suitable for ASFV serological monitoring and diagnosis application.

This invention discloses a kit for detecting porcine reproductive and respiratory syndrome virus (PRRSV) antibodies and its applications, belonging to the field of animal disease detection technology. The kit uses a mutant nucleocapsid protein (N protein) of the PRRSV-2 class NADC30 strain CHsx1401 as the coating antigen; the N protein mutant has mutations at amino acid positions 23, 75, and / or 90 compared to the wild-type N protein. High purity is achieved through optimized prokaryotic expression systems and purification processes. Under optimal detection conditions, the kit exhibits strong specificity, high sensitivity, and good reproducibility, with significantly superior detection performance compared to existing commercial kits. It can be used for PRRSV-2 antibody detection, epidemiological surveys, and disease control.

This invention constructs pET-32a-CP1 and pET-32a-CP2 expression vectors based on the CP1 and CP2 protein genes of Giardia duodenalis, transforms them into Rosetta (DE3) competent cells, and induces expression using IPTG. After SDS-PAGE analysis of the recombinant protein expression, Ni-NTA affinity chromatography is used to purify the proteins. Two indirect ELISA methods are then established using these as coating antigens. The indirect ELISA methods based on the recombinant proteins CP1 and CP2 of this invention exhibit good specificity, sensitivity, and repeatability, with concordance rates of 98% and 94% with microscopic detection results, respectively.

The invention discloses an OVA-D fluorescence immunochromatography detection test strip in a surimi product and application thereof, the test strip comprises a substrate, a sample adding pad, a combination pad, a reaction film and a water absorption pad, the sample adding pad, the combination pad, the reaction film and the water absorption pad are arranged on the substrate, the reaction film is arranged in the middle of the substrate, one end of the sample adding pad is in contact with the other end of the combination pad, one end of the combination pad is in contact with the other end of the reaction film, and the other end of the reaction film is in contact with the water absorption pad. One end of the reaction film contacts with the other end of the water absorption pad; the combination pad contains a rabbit anti-OVA-D polyclonal antibody marked by fluorescent quantum dots and goat IgG marked by fluorescent quantum dots; the reaction film is provided with a detection area, the detection area is sequentially provided with a detection line and a control line from the other end to one end of the reaction film, the detection line is coated with an OVA-D antigen, and the control line is coated with a rabbit anti-goat IgG antibody. The fluorescence signal is stable, the fluorescence intensity of the T line and the C line is not influenced by a complex matrix in a detected sample, the detection sensitivity is higher, and the reliability of quantitative detection of the duck egg ovalbumin is also ensured.

The invention discloses a lateral flow biosensor for joint detection of SAA and CRP based on an AIE material and application, the lateral flow biosensor comprises a sample pad, a combination pad, a nitrocellulose membrane and a water absorption pad, the combination pad is coated with fluorescent nano-microsphere labeled antibodies AIE490NP-SAA, AIE490NP-RIgG and AIE610NP-CRP, and the nitrocellulose membrane is coated with fluorescent nano-microsphere labeled antibodies AIE490NP-RIgG and AIE610NP-CRP. A detection line T line and a quality control line C line are sprayed on the nitrocellulose membrane, the T line is formed by an SAA coating antigen and a CRP coating antigen which are coated on the nitrocellulose membrane, and the C line is formed by a goat anti-rabbit IgG antibody coated on the nitrocellulose membrane. The prepared lateral flow biosensor can simultaneously detect CRP and SAA, has high sensitivity and good repeatability, and has wide application prospects in differential diagnosis of early infectious diseases.

The invention discloses a chemiluminiscence detection reagent for detecting an HCV antibody and a use method of the chemiluminiscence detection reagent, and relates to the technical field of immunodetection. The detection reagent is combined with a sandwich method and an indirect method for detection. When in use, a sample is incubated with the first reagent and the sample treating fluid, so that the HCV antibody to be detected in the sample reacts with the HCV coating antigen in the first reagent to form an antigen-antibody compound; adding a second reagent, and reacting the formed antigen-antibody compound with the HCV labeled antigen labeled by acridinium ester and the anti-IgG antibody labeled by acridinium ester in the second reagent to form an antigen-antibody-antigen compound and an antigen-antibody-secondary antibody compound; and finally, adding excitation liquid to enable acridinium ester to emit light, and detecting the HCV antibody in the sample by detecting a light-emitting signal value. The technical scheme of the invention greatly improves the sensitivity and specificity of HCV antibody detection, and can be used for solving the problem of easy missing detection in HCV antibody detection.

The invention discloses a monospecific monoclonal antibody for resisting zearalenone-14 glucoside and application of the monospecific monoclonal antibody. An immunogen and a coating antigen are used; the monoclonal antibody capable of monospecifically recognizing the zearalenone-14 glucoside and the rapid detection kit for detecting the zearalenone-14 glucoside are obtained through the technologies of mouse immunization, serum detection, cell fusion, monoclonal screening, ascites induced antibody and the like. The method is suitable for single-specificity trace residue detection of the zearalenone-14 glucoside in samples such as corn, rice, millet, wheat and oat, has very high recognition sensitivity to the zearalenone-14 glucoside, and realizes rapid, large-batch and low-cost detection of the zearalenone-14 glucoside.

The application discloses a kind of for HBV PreS1 antibody qualitative detection test strip and its preparation method and application, it is related to virology, immunology, biological detection technology and immunochromatography analysis technical field.The test strip is based on the specific recognition principle of antigen and antibody, the specific binding of PreS1 antigen and PreS1 antibody is realized, the rapid detection of PreS1 antibody in serum or plasma sample, it is sequentially assembled by sample pad, gold mark pad, nitrocellulose membrane (NC membrane) and water absorption pad, wherein, gold mark pad is fixed with colloidal gold labeled anti-human IgG antibody as gold mark probe, NC membrane detection line (T line) is coated HBV PreS1 antigen, for capturing PreS1 antibody in sample, NC membrane quality control line (C line) is coated HB2 antibody, for judging whether the test strip detection process is effective.The test strip in the application does not need complex instrument equipment, detection process is simple, fast and fast, and has good sensitivity and specificity, can be used for hepatitis B vaccine immune effect evaluation and large-scale screening.

The invention belongs to the technical field of antigen-antibody detection, and relates to a monoclonal antibody of a non-biphenyl tetrazolsartan drug, a nucleic acid molecule, a detection kit and application thereof. The monoclonal antibody of the non-biphenyl tetrazolsartan medicine comprises a heavy chain variable region (VH) and a light chain variable region (VL), the heavy chain variable region comprises a VH-CDR1, a VH-CDR2 and a VH-CDR3, the light chain variable region comprises a VL-CDR1, a VL-CDR2 and a VL-CDR3, the sequence of the VH-CDR1 is as shown in SEQ ID NO.1, and the sequence of the VH-CDR2 is as shown in SEQ ID NO.2. The monoclonal antibody of the non-biphenyl tetrazolsartan medicine has the advantages that the monoclonal antibody of the non-biphenyl tetrazolsartan medicine can be used for preparing the non-biphenyl tetrazolsartan medicine; the monoclonal antibody capable of simultaneously recognizing azilsartan and telmisartan is successfully prepared by taking candesartan as an immunogen and azilsartan as a coating antigen, the azilsartan and telmisartan are specifically detected, and the problem that the two drugs cannot be covered by the existing immunodetection technology is solved.

The application provides a fusion protein for detecting aquaporin 4 antibody and a preparation method and application thereof, and belongs to the technical field of aquaporin 4 antibody detection. The nucleotide sequence of the fusion protein is shown as SEQ ID NO. 5, the fusion protein is used as a coating antigen, and M1 type and M23 type aquaporin 4 can be simultaneously detected. The sensitivity and accuracy of the aquaporin 4 antibody detection are high, and the repeatability is good. When the kit of the application is used for aquaporin 4 antibody, the detection method is simple and rapid, and is suitable for large-scale screening of aquaporin 4 antibody in clinical and scientific research.

The invention provides a hybridoma cell strain secreting a toxoflavin monoclonal antibody. The hybridoma cell strain is obtained by immunogen immune animals prepared by coupling toxoflavin hapten and carrier protein. Wherein the carrier protein for preparing the immunogen comprises keyhole limpet hemocyanin KLH. The hybridoma cell strain is preserved in the Guangdong Microbial Culture Collection Center on March 10, 2026, and the preservation number is GDMCC (China General Microbiological Culture Collection Center) No.67912. The invention also provides an application of the hybridoma cell strain, specifically, the toxoflavin monoclonal antibody secreted by the hybridoma cell strain is applied to toxoflavin detection. The kit further comprises a coating antigen, the coating antigen is prepared by coupling the toxoflavin hapten and carrier protein, and the carrier protein for preparing the coating antigen comprises bovine serum albumin (BSA). The monoclonal antibody secreted by the hybridoma cell strain has good sensitivity and specificity to toxoflavin, and can be accurately and reliably used for quantitative detection of toxoflavin in an actual sample.

The application discloses a competitive ELISA detection method for Hib polysaccharide in an aluminum-containing adjuvant vaccine, and specifically, the method comprises the following steps: enzyme label plate preparation: coating Hib stock solution or PRP derivative on an enzyme label plate to prepare an enzyme label plate required for ELISA reaction; aluminum adsorption Hib sample treatment: blocking aluminum adjuvant adsorbed Hib reference and aluminum adjuvant containing vaccine samples with BSA, respectively, and then diluting the aluminum adjuvant adsorbed Hib reference and aluminum adjuvant combined vaccine samples after blocking; ELISA detection: adding the diluted aluminum adjuvant adsorbed Hib reference and aluminum adjuvant containing vaccine samples into the enzyme label plate, respectively, and then adding Hib specific antibody, generating ELISA signals through enzyme label antibody catalysis of substrates, establishing a mathematical relationship between absorbance and Hib polysaccharide content, and quantitatively calculating the Hib polysaccharide content in the aluminum adjuvant containing vaccine sample.

The invention relates to an electrochemical luminescence immunosensor and application thereof in detection of DON, and belongs to the technical field of immunoassay. The electrochemical luminescence immunosensor comprises an electrochemical luminescence probe and an electrochemical luminescence electrode, the electrochemical luminescence probe comprises Eu-MOF, and the Eu-MOF is connected with a deoxynivalenol antibody through a chemical bond; the electrochemical luminescence electrode comprises an electrode body, the electrode body is modified with Au (at) Sn3O4, and the Au (at) Sn3O4 is connected with a deoxynivalenol coating antigen through a chemical bond. According to the present invention, the electrochemical immunosensor using Eu-MOF as the illuminant and potassium persulfate as the only co-reactant is developed, such that the purpose of sensitive detection of deoxynivalenol in cereals is achieved, and the important significance in food safety monitoring is provided. The sensor system is integrated, simple and convenient to control, rapid in trace amount, simple and convenient in pretreatment, high in sensitivity, wide in linear range, high in universality, controllable in cost and outstanding in practical value.

The application provides a colorimetric-fluorescent dual-mode determination method for hydrophobic anticancer drug curcumin, and the application realizes the preparation of oil amine branch joint polysuccinimide loaded curcumin (CUR@PSI OAm ) coated antigen, dual-mode probe labeled anti-PSI OAm antibody, and specific combination of antigen-antibody reaction for dual-mode ultra-trace detection and analysis of CUR@PSI OAm in cells, and indirect quantitative detection of hydrophobic anticancer drug curcumin in cells. Compared with the prior art, the dual-mode analysis method provided by the application can be mutually supported, and does not need to be enriched and preprocessed, is simple to operate, has short detection time, has the characteristics of high throughput, high sensitivity, high specificity, precise targeting and non-destructive detection, and can be used for ultra-trace non-destructive detection and analysis of hydrophobic anticancer drug curcumin (CUR) in cells.

The invention discloses a duck circovirus ELISA antibody detection kit and application thereof, and relates to the technical field of biological detection. The duck circovirus ELISA antibody detection kit comprises a detection plate, wherein the detection plate is coated with duck circovirus Cap protein; wherein the duck circovirus Cap protein is obtained through expression of a eukaryotic expression system. The Cap protein prepared by using an eukaryotic expression system is used as a coating antigen, has good antigenicity, can be specifically combined with a duck circovirus antibody in a serum sample, and ensures that the provided kit has very strong specificity and sensitivity to the duck circovirus. According to the duck circovirus ELISA antibody detection kit provided by the invention, the duck circovirus antibody can be rapidly and accurately detected, and the problems of poor antigen quality and unstable detection performance of the existing duck circovirus ELISA antibody detection method are solved.

The present application relates to an enzyme labeled plate and a preparation method thereof, and belongs to the technical field of enzyme labeled plates. The enzyme labeled plate comprises a solid carrier and a functional layer arranged on the surface of the solid carrier; the raw material of the solid carrier comprises aminated polystyrene and polystyrene; and the surface of the solid carrier is treated by hydrophilic modification to form the functional layer. Because the aminated polystyrene contains an amino active group, the surface activity of the enzyme labeled plate can be improved, then the surface of the solid carrier is treated by hydrophilic modification to form the functional layer, so that the surface of the enzyme labeled plate can produce strong adsorption and strong reaction activity with protein molecules such as antigens or antibodies, the effect of coating the enzyme labeled plate with protein molecules such as antigens or antibodies is improved, and the sensitivity of ELISA testing is improved.

The application discloses an ELISA method for detecting porcine epidemic diarrhea virus antibody SIgA and belongs to the technical field of biology. The method comprises the steps of taking S1 protein as a coating antigen and detecting porcine epidemic diarrhea virus antibody SIgA in a sample to be detected, wherein the amino acid sequence of the S1 protein is a truncated sequence from the 19th to the 719th. The application preliminarily establishes an indirect ELISA method for detecting porcine epidemic diarrhea virus specific SIgA antibodies in serum, intestinal tissue and milk by optimizing conditions, and determines that the optimal antigen coating concentration and coating time are 0.25 mu g / ml and 4 DEG C overnight 12h-16h respectively, and the optimal detection conditions are determined. The method for detecting PEDV specific SIgA in serum, intestinal tissue and milk established in the research is simple and rapid, has good sensitivity and specificity, and provides a basis and a detection standard for evaluating the mucosal immune level of PEDV.

The invention discloses preparation of an akabane disease virus N protein monoclonal antibody and a double-antibody sandwich ELISA (Enzyme-Linked Immunosorbent Assay) detection method, in order to prepare the akabane disease virus nucleocapsid protein monoclonal antibody, an eukaryotic recombinant plasmid pFastBac-AKAV-N is constructed and is converted into a DH10bac competent cell, and a recombinant stem Bacmid-AKAV-N for expressing AKAV N is successfully obtained. After the recombinant baculovirus is transfected to an sf9 insect cell, the recombinant baculovirus capable of stably expressing the AKAV N protein is rescued. A mouse and a rabbit are immunized with the identified and purified recombinant N protein, and a monoclonal antibody and a polyclonal antibody are prepared respectively. The titer of the polyclonal antibody is measured through an ELISA method, and two positive cell strains are obtained through screening and are named as 2G4 and 6C7 respectively. Furthermore, the prepared polyclonal antibody is used as a coating antigen, an HRP-labeled 2G4 monoclonal antibody is used as a detection antibody, and a double-antibody sandwich ELISA detection method for AKAV N protein antigen detection is optimized and established. According to the method, the AKAV N antigen can be specifically recognized, and reliable technical support is provided for clinical antigen monitoring of AKAV. The monoclonal antibody preparation system and the double-antibody sandwich ELISA detection method established by the invention lay an important foundation for pathogen detection and epidemiological investigation of akabane disease.

This invention discloses a qualitative test strip for HBV PreS1 antibody, its preparation method, and its applications, relating to the fields of virology, immunology, biodetection technology, and immunochromatographic analysis. Based on the principle of antigen-antibody specific recognition, the test strip achieves rapid detection of PreS1 antibodies in serum or plasma samples through the specific binding of PreS1 antigen and PreS1 antibody. It is assembled sequentially from a sample pad, a gold-labeled pad, a nitrocellulose membrane (NC membrane), and an absorbent pad. The gold-labeled pad is immobilized with colloidal gold-labeled anti-human IgG antibody as a gold probe. The NC membrane detection line (T line) is coated with HBV PreS1 antigen to capture PreS1 antibodies in the sample, and the NC membrane control line (C line) is coated with HB2 antibody to determine the effectiveness of the test strip's detection process. The test strip of this invention requires no complex instruments or equipment, the detection process is simple, rapid, and has good sensitivity and specificity, making it suitable for evaluating the immunization efficacy of hepatitis B vaccines and for large-scale screening.

This invention discloses a highly sensitive glycocholic acid single-chain antibody, its screening method, and its application. The aim is to provide a highly sensitive glycocholic acid single-chain antibody that can be used for rapid immunodetection of glycocholic acid and has good application value. Its amino acid sequence is shown in SEQ ID NO. 1. The single-chain antibody is obtained by immunizing animals with a glycocholic acid immunogen and screening using a heterologous coated antigen. This invention relates to the field of biotechnology.

This invention relates to an indirect ELISA detection kit for *Bacteroides argyrophyllinoides* antibodies and its application, belonging to the field of biodetection technology. To address the shortcomings of existing bacterial isolation, identification, and PCR detection methods for *Bacteroides argyrophyllinoides*, and the lack of serological identification methods for this bacterium in current technologies, this invention uses the outer membrane protein Omp1D of *Bacteroides argyrophyllinoides* as the coating antigen in the indirect ELISA detection kit. This enables rapid detection and screening of *Bacteroides argyrophyllinoides* infection in cattle and sheep, featuring simple operation, high sensitivity, accurate results, good specificity, and good reproducibility. Furthermore, the *Bacteroides argyrophyllinoides* antibody indirect ELISA detection kit is characterized by simple preparation method, low cost, and suitability for large-scale production. It provides a rapid, simple, and sensitive diagnostic kit for detecting *Bacteroides argyrophyllinoides* infection in large-scale livestock farming, offering technical support for the prevention and control of *Bacteroides argyrophyllinoides* infection.

The application discloses a kind of gold cluster-manganese dioxide nanosheet-based pesticide fluorescence immunoassay method.Currently, it is still challenging to develop a high-sensitivity, strong anti-interference ability analysis method to detect pesticides in complex food matrix.In the present application, coated antigen competes with pesticide to recognize enzyme-labeled antibody.After competitive immune reaction, ALP catalyzes substrate to produce ascorbic acid, which triggers the decomposition of AuNCs-MnO2NFs and regulates fluorescence reaction.Methidathion is selected as the analyte to be detected by the method.The results show that the fluorescence immunoassay method has high detection sensitivity (IC 10 = 5.78 pg mL ‑1 ), which is about 56 times higher than the traditional enzyme-linked immunoassay.The present application is successfully used for precise monitoring of pesticide residues and degradation dynamics in pakchoi, and has good anti-interference ability and reproducibility, paving the way for pesticide residue determination in actual samples.

The application discloses a BVDV antigen capture ELISA method and kit based on rCD46 and rE2 monoclonal antibodies, and the expression strain is preserved in the China General Microbiological Culture Collection Center on July 24, 2024, with a preservation number of CGMCC NO: 31440; the monoclonal antibody hybridoma cell strain E2mAb strain is preserved in the China General Microbiological Culture Collection Center on October 09, 2024, with a preservation number of CGMCC NO: 46055. The application establishes a BVDV antigen capture ELISA detection method by using a BVDV receptor rCD46 protein as a coating antigen and using HRP-labeled specific rE2 monoclonal antibodies as detection antibodies, and domestic BVDV antigen capture ELISA detection kits based on the receptor rCD46 and the BVDV rE2 monoclonal antibodies are assembled for the first time.

The invention relates to a hepatitis A virus (HAV) fusion protein as well as a preparation method and application thereof, prokaryotic expression and purification are carried out based on connection and fusion of main antigen regions of HAV capsid proteins VP1 and VP3, a high-purity HAV-rVP13 fusion protein is obtained, the HAV-rVP13 fusion protein is used as a coating antigen, and an ELISA detection method for an HAV specific IgG antibody is established. By establishing an enterprise calibrator and a quality control product and calibrating by a national HAV specific IgG standard product, the established ELISA detection method can quantitatively determine the concentration of the HAV specific IgG antibody in human plasma / serum, has very high sensitivity and specificity, and can be used for quantitative detection of the HAV IgG antibody in a human plasma / serum sample.

The application discloses a pig SLPI monoclonal antibody and application thereof, and belongs to the field of biotechnology and cell engineering. The application immunizes mice with a His-SLPI recombinant protein, and carries out cell fusion when the serum titer reaches 1:10000 or above. On the seventh day of the fusion, indirect ELISA is carried out on cell supernatant, and positive wells with higher OD values are screened out. The purified recombinant GST-SLPI protein is used as a coating antigen, the wells are expanded and cultured, and the cells are made into single cells in single wells by using an effective dilution method. After continuous screening to obtain 100% positive wells, the supernatant of the positive cells is used for specific identification of the pig-derived SLPI protein by Western blot and IFA. One hybridoma strain B with a higher binding titer is obtained by identification, the heavy chain amino acid sequence of the SLPI monoclonal antibody produced by the hybridoma strain B is shown as SEQ ID NO. 1, and the light chain amino acid sequence is shown as SEQ ID NO. 2.

This invention provides a kit based on a three-phase enzyme-linked immunosorbent assay (ELISA) and its application. The construction of the three-phase ELISA sensor in the kit mainly includes the following steps: first, selecting a hydrophobic substrate, washing and pretreating it; second, immobilizing the coated antigen and oxidase on the substrate. This invention develops a competitive immunoassay method based on a three-phase substrate and applies it to the detection of 5-fluorouracil. This invention utilizes the specific immunoreaction between a collaboratively developed 5-fluorouracil monoclonal antibody and the antigen to quantitatively detect 5-fluorouracil, improving the selectivity for the target analyte. This immunosensor uses inexpensive equipment, is easy to operate, has high detection efficiency, simple sample processing, and exhibits a wide linear range and a high detection upper limit, making it easy to popularize and cost-effective, thus possessing high practical value.