Tehran University of Medical Sciences Journal of Food Safety and Hygiene 2476-3241 2 3/4 2018 03 07 75 83 Wenjun Wang College of Grain, oil and food, Henan University of technology, Zhengzhou, PR China AND Beijing ZYD Technology Corporation Ltd, Beijing, PR China Jinxin He Beijing Key Laboratory of Biodiversity and Organic Farming, College of Resources and Environmental Sciences, China Agricultural University, Beijing, China Han Xiao College of Science, Beijing Jiao tong University, Beijing , PR China Xueling Zheng College of Grain, oil and food, Henan University of technology, Zhengzhou, PR China Limin Li College of Grain, oil and food, Henan University of technology, Zhengzhou, PR China 2018 03 08 Dexamethasone (DEX) is a potent glucocorticoid that was widely employed in livestock production. In the present study, a one-step indirect competitive enzyme-linked immunosorbent assay (icELISA) was developed for the determination of DEX residue in animal-origin food. With this aim, hapten DEX-3c was firstly synthesized, conjugated to carrier protein, and then used as immunogen in rabbits. Polyclonal antibody was subsequently obtained and characterized. The half-maximal inhibition concentrations (IC50) and the limit of detection (LOD, calculated as IC20) of the icELISA for DEX were approximately 0.061 and 0.015 ng/mL, respectively. The antibody exhibited significantly cross-reactivity with some of DEX structural analogs. The average recoveries and coefficients of variation (CVs) of DEX from fortified samples by icELISA were in a range of 83.3- 114.2% and 5.6-9.5%, respectively. The LOD of this assay for DEX in chicken muscle and liver extracts was 0.3 μg/kg and 0.5 μg/kg, respectively. https://jfsh.tums.ac.ir/index.php/jfsh/article/view/108 https://jfsh.tums.ac.ir/index.php/jfsh/article/download/108/53