title: Rapid determination of trace copper in animal feed based on micro-plate colorimetric reaction and statistical partitioning correction.
abstract: The objective of this study was to develop a micro-plate based colorimetric assay for rapid and high-throughput detection of copper in animal feed. Copper ion in animal feed was extracted by trichloroacetic acid solution and reduced to cuprous ion by hydroxylamine. The cuprous ion can chelate with 2,2'-bicinchoninic acid to form a Cu-BCA complex which was detected with high sensitivity by micro-plate reader at 354nm. The whole assay procedure can be completed within 20min. To eliminate matrix interference, a statistical partitioning correction approach was proposed, which makes the detection of copper in complex samples possible. The limit of detection was 0.035μg/mL and the detection range was 0.1-10μg/mL of copper in buffer solution. Actual sample analysis indicated that this colorimetric assay produced results consistent with atomic absorption spectrometry analysis. These results demonstrated that the developed assay can be used for rapid determination of copper in animal feed.
authors.affiliation: State Key Laboratory of Animal Nutrition, College of Animal Science and Technology, China Agricultural University, Beijing 100193, China.
authors.forename: Yiming
authors.initials: Y
authors.lastname: Niu
authors.affiliation: State Key Laboratory of Animal Nutrition, College of Animal Science and Technology, China Agricultural University, Beijing 100193, China.
authors.forename: Jiayi
authors.initials: J
authors.lastname: Wang
authors.affiliation: State Key Laboratory of Animal Nutrition, College of Animal Science and Technology, China Agricultural University, Beijing 100193, China.
authors.forename: Chi
authors.initials: C
authors.lastname: Zhang
authors.affiliation: State Key Laboratory of Animal Nutrition, College of Animal Science and Technology, China Agricultural University, Beijing 100193, China. Electronic address: yqchen@cau.edu.cn.
authors.forename: Yiqiang
authors.initials: Y
authors.lastname: Chen
mesh_terms: D000821:Animal Feed / Q000032:analysis*; D000818:Animals; D003124:Colorimetry / Q000379:methods*; D003300:Copper / Q000032:analysis*
chemical_list: D003300:Copper
keywords: 2,2′-Bicinchoninic acid; Animal feed; Colorimetric assay; Copper