Dexamethasone,a long-acting glucocorticoid,exhibits considerable structural similarity to other glucocorticoids.To avoid false-positive results in immunoassays due to cross-reactivity of antibodies with structural ana...Dexamethasone,a long-acting glucocorticoid,exhibits considerable structural similarity to other glucocorticoids.To avoid false-positive results in immunoassays due to cross-reactivity of antibodies with structural analogues,the preparation of highly specific antibodies is crucial.In this study,a novel hapten DEX-GA was designed and synthesized,and the monoclonal antibody(mAb)3D1 was successfully prepared based on the hapten.The mAb 3D1 has the 50%inhibitory concentration of 0.38 ng/mL for dexamethasone,with cross-reactivity below 7.45%against twelve glucocorticoids including betamethasone,prednisone,triamcinolone and beclomethasone.Based on this antibody,indirect competitive enzyme-linked immunosorbent assay(ic-ELISA)and colloidal gold immunochromatography assay(GICA)were developed for accurate detection of dexamethasone in milk and animal tissues.The limits of detection of ic-ELISA in milk and animal tissues ranged from 0.132 to 0.215μg/kg,which was a 1-3-fold increase in sensitivity compared with the previously reported ic-ELISA method.The GICA method established in this study had a visual limit of detection of 0.3μg/L in milk.Notably,this constitutes the first application of GICA in animal tissues,demonstrating a visual detection limit of 0.2μg/kg.The accuracy and reliability of both ic-ELISA and GICA were validated using liquid chromatography-tandem mass spectrometry.展开更多
基金funded by the National Natural Science Founda-tion of China(32573424)the National Key Research and Development Programs of China(2023YFD1301001,2024YFF1105705)the Hubei Provincial Natural Science Foundation(2024AFB146).
文摘Dexamethasone,a long-acting glucocorticoid,exhibits considerable structural similarity to other glucocorticoids.To avoid false-positive results in immunoassays due to cross-reactivity of antibodies with structural analogues,the preparation of highly specific antibodies is crucial.In this study,a novel hapten DEX-GA was designed and synthesized,and the monoclonal antibody(mAb)3D1 was successfully prepared based on the hapten.The mAb 3D1 has the 50%inhibitory concentration of 0.38 ng/mL for dexamethasone,with cross-reactivity below 7.45%against twelve glucocorticoids including betamethasone,prednisone,triamcinolone and beclomethasone.Based on this antibody,indirect competitive enzyme-linked immunosorbent assay(ic-ELISA)and colloidal gold immunochromatography assay(GICA)were developed for accurate detection of dexamethasone in milk and animal tissues.The limits of detection of ic-ELISA in milk and animal tissues ranged from 0.132 to 0.215μg/kg,which was a 1-3-fold increase in sensitivity compared with the previously reported ic-ELISA method.The GICA method established in this study had a visual limit of detection of 0.3μg/L in milk.Notably,this constitutes the first application of GICA in animal tissues,demonstrating a visual detection limit of 0.2μg/kg.The accuracy and reliability of both ic-ELISA and GICA were validated using liquid chromatography-tandem mass spectrometry.
