Xiujin Chen,Zhaozhou Li,Fengxia Sun,Xiaotian Cao,Yao Wang,Li Cao,Hongli Gao,Dong Gao,Yawen Wang
Tebuconazole is widely applied for controlling pathogenic fungi of crops and proved hazardous to human being. To better measure tebuconazole residues, an enzyme-linked immunosorbent assay for screening tebuconazole residues in aqueous samples was established using an innovative hapten (hapten1) designed via molecular model. The work concentration of calibration standard curves based on aqueous matrices ranged from 0.51 to 10.71 ng mL–1. The cross-reactivities of other analogs were less than 6%. The detection limits of the assay were in the range of 0.197–0.297 ng mL–1 for tebuconazole in water samples. The average recoveries of tebuconazole in the spiked water samples varied from 76.76% to 107.52% with the variation coefficient scope of 4.54–13.26%. The obtained immunoassay was verified by gas chromatography coupled to mass spectrometry with high correlation coefficients (r > 0.9868). Herein, the proposed immunoassay offers a cost-effective, convenient, reliable tool for the determination of tebuconazole residues in aqueous samples.
Histamine (HA) is an essential test item for fishery samples. However, the fast and effective determination of HA is difficult due to its simple structure and small molecular size. In this study, a sensitive and specific monoclonal antibody against p-nitrobenzoylated histamine (NPHA), which can be easily obtained from the reaction of HA and p-nitrobenzoic acid N-hydroxysuccinimide ester (PNBA-OSu) under mild conditions, was generated for the first time. Based on this mAb, an immunochromato-graphic assay strip (ICA strip) using a colloidal gold nano particles-antibody (GNPs) probe for rapid detection of HA in saury samples was established. After screening the coating antigens and optimization of analytical parameters, a heterologous coating based ICA strip exhibited the most excellent detection ability with a visual detection limit (VDL) of 6.0 mg kg−1 in qualitative experiments and a detection limit (by a strip reader) of 1.0 mg kg−1 in semi-quantitative experiments for saury samples, with no cross-reactivity with HA analogs. Good correlation between the ICA strip with liquid chromatography-tandem mass spectrometry was achieved for spiked and naturally contaminated saury samples. Overall, this method is suitable for screening of HA residue for large scale fish samples in a quick, simple and low-cost manner.
Lu Zeng,Shanshan Song,Qiankun Zheng,Pengjie Luo,Xiaoling Wu,Hua Kuang
Shrimp tropomyosin is one of the most important causes of shellfish allergy. The objective of this study was to develop a highly sensitive and specific immunoassay for the detection of shrimp tropomyosin in food. Ten monoclonal antibodies against shrimp tropomyosin were obtained by fusion and cell screening. We found two optimum monoclonal antibodies (mAbs); mAb 2 was used as the capture antibody, and HRP-labelled mAb 3 was used as the detection antibody. Using this pair of mAbs, a sandwich enzyme-linked immunosorbent assay (ELISA) was developed with the limit of detection (LOD) of 0.45 ng/mL. Cross-reactivity with other food allergens using this method was found to be negligible. An immunochromatographic assay strip was also developed for the rapid detection of shrimp tropomyosin with the LOD of 0.5 ng/mL. The results demonstrated that our developmental methods represent a useful tool for the detection of shrimp tropomyosin in food.
危险品化学品经营许可证（带存储）