A fluorescence polarization immunoassay(FPIA) for the determination of salinomycin(SAL) was developed by using anti-SAL monoclonal antibodies(mAb).Fluorescein labeled SAL(tracer) was synthesized by the N-hydroxysuccin...A fluorescence polarization immunoassay(FPIA) for the determination of salinomycin(SAL) was developed by using anti-SAL monoclonal antibodies(mAb).Fluorescein labeled SAL(tracer) was synthesized by the N-hydroxysuccinimide active ester method and purified using thin layer chromatography(TLC).The developed FPIA for SAL had a dynamic range from 0.60 to 2193 ng/mL with an IC50 value of 33.2 ng/mL and a detection limit(LOD) of 0.08 ng/mL.No significant cross-reactivities were observed with other drugs but 67.6% with narasin.展开更多
Objective Determination of estrone (E1) levels has a significant meaning in evaluating physiological effect and diagnosing some diseases. In order to detect free E1 in biological fluids, a monoclonal antibody specifi...Objective Determination of estrone (E1) levels has a significant meaning in evaluating physiological effect and diagnosing some diseases. In order to detect free E1 in biological fluids, a monoclonal antibody specific for E1 was prepared after the complete antigen of E1 was synthesized. The purified monoclonal antibody was fully characterized for later immunoassay. Methods 3-O-carboxymethyl ether derivative of E1 was synthesized and in turn coupled to bovine serum albumin (BSA) to form complete antigen E1-BSA. A monoclonal antibody (McAb) specific for E1 was produced both in vitro and in vivo by a hybridoma anti-E1. Anti-E1 was prepared by fusion of SP2/0 murine myeloma cells with spleen cells isolated from immunized BALB/c mouse. The McAb was characterized by enzyme-linked immunosorbent assay (ELISA), SDS-PAGE and Western-blotting. The specificity of the immunoassay was investigated by determining the cross-reactions of E1 analogs when free E1 was detected by competitive indirect enzyme-linked immunosorbent assay (CI-ELISA). Results Analysis revealed that anti-E1 McAb (E1-McAb) was of the IgG1 type, the molecular weight of E1-McAb was 164 000 daltons. The affinity constant of E1-McAb with coated complete antigen was 8.2108L/mol. The linear range for free E1 determined by CI-ELISA was 10pg/mL^10ng/mL. The detection limit was 21.4 pg/mL (defined as twice the standard deviation of the blank). Conclusion The CI-ELISA developed with E1-McAb was both sensitive and specific. The prepared E1-McAb can be used in some immunoassays.展开更多
Human epidermal growth factor receptor 2(HER2)is an important biomarker for detection and treatment of breast cancer.In this study,we developed monoclonal antibodies against the extracellular domain(ECD)of HER2 and es...Human epidermal growth factor receptor 2(HER2)is an important biomarker for detection and treatment of breast cancer.In this study,we developed monoclonal antibodies against the extracellular domain(ECD)of HER2 and established a rapid and accurate lateral flow immunoassay(LFIA)for use in community medical institutions.The gene sequence of human HER2-ECD was obtained from the National Center for Biotechnology Information(NCBI)to construct the expression plasmid.HER2-ECD protein expressed in HEK293F cells was used to immunize BALB/c mice.The monoclonal antibodies were produced in mouse ascites and isolated by hybridoma cell screening.Antibodies were analyzed for purity by SDS-PAGE(sodium dodecyl sulphate-polyacrylamide gel-electrophoresis)and affinity was assessed by enzyme-linked immunosorbent assay(ELISA)while subtypes were detected using the commercial kits.The HER2-ECD test strip was prepared based on the sandwich method and evaluated using a portable detection instrument.The affinity of the paired antibodies,4D8 and 8D9,both reached 1×108 L/mol.Both antibodies specifically recognized the HER2-ECD protein in serum.The limit of detection(LOD)of the gold nanoparticle(AuNP)-based LFIA was 1.7 ng/mL with a detection range of 1.7-400 ng/mL,and the performance of the HER2-ECD strip correlated well with that of a Siemens chemiluminescent immunoassay(CLIA)kit.In conclusion,the paired antibodies were successfully prepared with high affinity and specificity.The AuNP-based LFIA of HER2-ECD provides a fast and accurate method to detect the concentration of HER2-ECD in serum samples for clinical use in community medical institutions,and could contribute to determining the progress of the disease or the effectiveness of treatment.展开更多
To reduce the false positive results caused by cross reactivity of the antibodies with other structural analogues,it is crucial to prepare a high specificity and sensitivity antibody against target for developing an a...To reduce the false positive results caused by cross reactivity of the antibodies with other structural analogues,it is crucial to prepare a high specificity and sensitivity antibody against target for developing an accurate immunoassay.In this study,tilmicosin(TM)was selected as a model molecule.Firstly,two-dimensional similarity,electrostatic potential energy,mulliken atomic charges and overlapping of different haptens with TM were calculated using Gaussian 09W and Discovery studio,and the newly designed TM-HS was selected as the optimal hapten.Furthermore,a monoclonal antibody(mAb 12C8)was produced with the half maximal inhibitory concentration(IC50)of 0.36 ng/mL,and negligible cross-reactivity(CR)with other antibiotics.Finally,a lateral flow immunoassay(LFA)for the detection of TM based on amorphous carbon nanoparticles(ACNPs)labeled mAb 12C8 was developed by the reflectance value under natural light.The recoveries of TM ranged from 83.18%to 103.25%with a coefficient of variation(CV)<12.47%.The results showed that the cut-off value of TM in milk samples was 1 ng/mL,and the limits of detection(LODs)for chicken muscle,bovine muscle,porcine muscle and porcine liver samples were 5.23,5.98,6.85 and 7.31μg/kg,respectively.In addition,40 real samples were tested by the LFA,and the detection results were consisted with that of high-performance liquid chromatography-UV detector(HPLC-UV).Those results indicated that the developed LFA is an accurate and useful tool for on-site screening of TM in milk and animal tissues.展开更多
基金support from the National Natural Science Foundation of China (Grant No 30830082)the Major State Basic Research Development Program of China (Grant No 2009CB118801)Beijing Excellent Doctoral Dissertation Fund (Grant No YB20081001902)
文摘A fluorescence polarization immunoassay(FPIA) for the determination of salinomycin(SAL) was developed by using anti-SAL monoclonal antibodies(mAb).Fluorescein labeled SAL(tracer) was synthesized by the N-hydroxysuccinimide active ester method and purified using thin layer chromatography(TLC).The developed FPIA for SAL had a dynamic range from 0.60 to 2193 ng/mL with an IC50 value of 33.2 ng/mL and a detection limit(LOD) of 0.08 ng/mL.No significant cross-reactivities were observed with other drugs but 67.6% with narasin.
基金This work was supported by National Science Foundation of China (Grant no.20075001).
文摘Objective Determination of estrone (E1) levels has a significant meaning in evaluating physiological effect and diagnosing some diseases. In order to detect free E1 in biological fluids, a monoclonal antibody specific for E1 was prepared after the complete antigen of E1 was synthesized. The purified monoclonal antibody was fully characterized for later immunoassay. Methods 3-O-carboxymethyl ether derivative of E1 was synthesized and in turn coupled to bovine serum albumin (BSA) to form complete antigen E1-BSA. A monoclonal antibody (McAb) specific for E1 was produced both in vitro and in vivo by a hybridoma anti-E1. Anti-E1 was prepared by fusion of SP2/0 murine myeloma cells with spleen cells isolated from immunized BALB/c mouse. The McAb was characterized by enzyme-linked immunosorbent assay (ELISA), SDS-PAGE and Western-blotting. The specificity of the immunoassay was investigated by determining the cross-reactions of E1 analogs when free E1 was detected by competitive indirect enzyme-linked immunosorbent assay (CI-ELISA). Results Analysis revealed that anti-E1 McAb (E1-McAb) was of the IgG1 type, the molecular weight of E1-McAb was 164 000 daltons. The affinity constant of E1-McAb with coated complete antigen was 8.2108L/mol. The linear range for free E1 determined by CI-ELISA was 10pg/mL^10ng/mL. The detection limit was 21.4 pg/mL (defined as twice the standard deviation of the blank). Conclusion The CI-ELISA developed with E1-McAb was both sensitive and specific. The prepared E1-McAb can be used in some immunoassays.
基金the National Natural Science Foundation of China(No.22236002)National Key R&D Program(Nos.2023YFF1105003 and 2022YFA1207300).
文摘Human epidermal growth factor receptor 2(HER2)is an important biomarker for detection and treatment of breast cancer.In this study,we developed monoclonal antibodies against the extracellular domain(ECD)of HER2 and established a rapid and accurate lateral flow immunoassay(LFIA)for use in community medical institutions.The gene sequence of human HER2-ECD was obtained from the National Center for Biotechnology Information(NCBI)to construct the expression plasmid.HER2-ECD protein expressed in HEK293F cells was used to immunize BALB/c mice.The monoclonal antibodies were produced in mouse ascites and isolated by hybridoma cell screening.Antibodies were analyzed for purity by SDS-PAGE(sodium dodecyl sulphate-polyacrylamide gel-electrophoresis)and affinity was assessed by enzyme-linked immunosorbent assay(ELISA)while subtypes were detected using the commercial kits.The HER2-ECD test strip was prepared based on the sandwich method and evaluated using a portable detection instrument.The affinity of the paired antibodies,4D8 and 8D9,both reached 1×108 L/mol.Both antibodies specifically recognized the HER2-ECD protein in serum.The limit of detection(LOD)of the gold nanoparticle(AuNP)-based LFIA was 1.7 ng/mL with a detection range of 1.7-400 ng/mL,and the performance of the HER2-ECD strip correlated well with that of a Siemens chemiluminescent immunoassay(CLIA)kit.In conclusion,the paired antibodies were successfully prepared with high affinity and specificity.The AuNP-based LFIA of HER2-ECD provides a fast and accurate method to detect the concentration of HER2-ECD in serum samples for clinical use in community medical institutions,and could contribute to determining the progress of the disease or the effectiveness of treatment.
基金supported by the Key Scientific and Technological Project of Henan Provincial Department of China(222102310162)the National Natural Science Foundation of China(32172298)+2 种基金the Young Talents Project of Henan Agricultural University(30501305)the Henan Postgraduate Joint Training Base Project(YJS2022JD16)the Program for Innovative Research Team(in Science and Technology),University of Henan Province(NO.23IRTSTHN023).
文摘To reduce the false positive results caused by cross reactivity of the antibodies with other structural analogues,it is crucial to prepare a high specificity and sensitivity antibody against target for developing an accurate immunoassay.In this study,tilmicosin(TM)was selected as a model molecule.Firstly,two-dimensional similarity,electrostatic potential energy,mulliken atomic charges and overlapping of different haptens with TM were calculated using Gaussian 09W and Discovery studio,and the newly designed TM-HS was selected as the optimal hapten.Furthermore,a monoclonal antibody(mAb 12C8)was produced with the half maximal inhibitory concentration(IC50)of 0.36 ng/mL,and negligible cross-reactivity(CR)with other antibiotics.Finally,a lateral flow immunoassay(LFA)for the detection of TM based on amorphous carbon nanoparticles(ACNPs)labeled mAb 12C8 was developed by the reflectance value under natural light.The recoveries of TM ranged from 83.18%to 103.25%with a coefficient of variation(CV)<12.47%.The results showed that the cut-off value of TM in milk samples was 1 ng/mL,and the limits of detection(LODs)for chicken muscle,bovine muscle,porcine muscle and porcine liver samples were 5.23,5.98,6.85 and 7.31μg/kg,respectively.In addition,40 real samples were tested by the LFA,and the detection results were consisted with that of high-performance liquid chromatography-UV detector(HPLC-UV).Those results indicated that the developed LFA is an accurate and useful tool for on-site screening of TM in milk and animal tissues.
