Preparation of an anti-dexamethasone monoclonal antibody and its use in development of a colloidal gold immunoassay

Abstract

A lateral flow colloidal gold (CG) immunoassay strip has been developed for detection of dexamethasone (DEX) residues in milk samples. For this purpose, an anti-DEX monoclonal antibody (McAb), based on a DEX succinic anhydride derivative hapten, was prepared and characterized. The McAb showed a high specificity to DEX, the half inhibitory concentration of the antibody was 0.095 ng/mL, its limit of detection (LOD) was 0.017 ng/mL, and its linear range of detection was 0.034-0.265 ng/mL. The developed CG immunoassay had a visual cutoff value of 0.3 ng/mL in phosphate buffered saline (PBS) and 0.5 ng/mL in milk samples. Each test requires 10 min. Analysis of DEX in milk indicated that the results of strip assay had a strong agreement with indirect competitive enzyme-linked immunosorbent assay. Therefore, the CG immunoassay is a sensitive screening method for semiquantitative and qualitative detection of DEX residues in milk samples.

Selection of high affinity aptamer-ligand for dexamethasone and its electrochemical biosensor

“…Therefore, accurate monitoring of the existence and the concentration of DXN in environmental and clinical samples is very important. The concentrations of DXN in real samples were found from sub nanomolar to micromolar range with different matrices 1 , 10 , 11 . Thus, the development of a rapid and sensitive detection method for the identification of DXN is required.…”

A sensitive lateral flow immunoassay for the multiple residues of five adamantanes

“…RMA-hapten (4-((1-((3r, 5r, 7r)-adamantan-1-yl)ethyl)amino)-4-oxobutanoic acid) was synthesized by the succinic anhydride method, which was the same as we reported in our previous work (Wang, Xie, et al, 2017;Wang, Zheng, et al, 2017). A mixture of RMA (1 g, 5.5 mmol) and succinic anhydride (0.66 g, 6.6 mmol) in 15 mL anhydrous pyridine was prepared and refluxed at 60°C for 12 h. Then, the mixture was dried using rotary evaporation, and the residue was dissolved in 15 mL of methanol aqueous solution (v/v, MeOH: H2O = 1:2).…”

“…The subclass of the mAb was determined using a mouse mAb isotyping (IgA, IgM, IgG 1 , IgG 2a , IgG 2b , IgG 3 ) kit (Cellway-lab, Luoyang, China). The affinity of the mAb against AMA and its analogues was determined according to previous studies (Beatty, Beatty, & Vlahos, 1987;Wang, Zheng, et al, 2017). In order to evaluate the performance of this mAb in the ic-ELISA, standard inhibition curves were established by plotting the optical density values at 450 nm obtained from each standard solution against the corresponding concentration of analyte.…”

Development of an immunochromatographic test strip for the detection of procaine in milk

“…Other analytical methods have also been used, including colorimetry (Lee & Livett, 1967;Salama & Omer, 1980), spectrophotometry (Liu et al, 2000), gas chromatography (Baniceru, Croitoru, & Popescu, 2004;Ohshima & Takayasu, 1999), high performance liquid chromatography (He, Peng, Tang, & Zhang, 2013;Liu, Peng, et al, 2017;Lu, 2012), and liquid chromatography tandem mass spectrometry (Babic et al, 2010;Dhananjeyan et al, 2007). However, these methods are time consuming and expensive because they require long pre-treatment procedures and sophisticated analytical instruments (Ge, Suryoprabowo, Zheng, & Kuang, 2017;Liu, Suryoprabowo, Zheng, Song, & Kuang, 2017;Wang, Zheng, et al, 2017).…”