Ultrasensitive immunochromatographic strip for detection of cyproheptadine

Gold-based immunochromatographic assay strip for the detection of quinclorac in foods

In this study, a highly specific and sensitive monoclonal antibody (mAb) against quinclorac (Qui) was prepared. Based on the selected mAb, 2G3, an indirect competitive enzyme-linked immunosorbent assay (ic-ELISA) and an immunochromatographic strip assay were established for the detection of Qui in actual samples. The 50%-inhibitory concentration of mAb 2G3 against Qui was 48.763 ng mL^-1. No cross-reaction with other quinolines indicated that mAb 2G3 had high specificity. The recovery of the established ic-ELISA method was in the range of 85.6% to 98.9%. The cut-off value of Qui in cucumber and tomato by immunochromatographic strip was 200 ng g^-1. The analysis results of ic-ELISA and immunochromatographic strip assay were consistent with the results of LC-MS/MS, which further proved that the established ic-ELISA and immunochromatographic strip assay could provide valuable tools for the rapid detection of Qui residues in cucumber and tomato samples.

Ultrasensitive immunochromatographic strip for the detection of cyhalothrin in foods

In this study, a highly specific and sensitive monoclonal antibody (mAb) against lambda-cyhalothrin (LCT) was prepared. The half maximal inhibitory concentration (IC₅₀) in the ic-ELISA was 1.2 ng mL^-1 and the limit of detection (LOD) value was 0.2 ng mL^-1. Based on the mAb, an immunochromatographic strip (ICS) was developed to qualitatively and quantitatively detect LCT in cabbage, parsley, spinach, and green tea samples. The results from the qualitative test can be observed with the naked eye within 10 min, and from quantitative detection experiments the linear detection ranges for cabbage, parsley, spinach, and green tea samples were 2.3-122.0, 1.5-98.2, 2.1-145.5, and 6.6-129.7 ng g^-1, respectively. Furthermore, recovery experiments were carried out at three spiked concentrations of LCT (5, 20, and 80 ng g^-1), and the recoveries of the ICS in vegetable samples ranged from 81.2% to 96.7%, with a coefficient of variation (CV) of less than 8.1%. For green tea, the recoveries of the ICS were from 80.4% to 90.7%, with a CV of less than 8.7%. The ICS assay established in this study can be used for the qualitative and quantitative determination of LCT residues in foods and agricultural products.

An ultrasensitive fluorescent paper sensor for fast screening of berberine

Berberine (BBR) is a highly effective animal feed additive, but it also has adverse side effects on animals and causes potential food safety issues. Based on BBR antibody preparation, fluorescent immunochromatography assay was established for quantitative detection of BBR in feed samples.

Hapten synthesis and antibody production for the development of a paper immunosensor for lean meat powder zilpaterol

An anti-zilpaterol mAb with an IC₅₀ of 0.31 ng mL⁻¹ and a limit of detection (LOD) of 0.02 ng mL⁻¹ has been developed. For semi-quantitative detection in pork samples, the visual LOD is 0.5 ng mL⁻¹ and the cut-off value is 5 ng mL⁻¹.

A colloidal gold immunochromatographic strip for quantitative detection of azoxystrobin in vegetables

Develop the immunochromatographic strip assay for rapid on-site screening of azoxystrobin in vegetables.

Development of an ic-ELISA and Immunochromatographic Strip Assay for the Detection of Diacetoxyscirpenol in Rice

Diacetoxyscirpenol (DAS) is a highly toxic type A trichothecene, a natural contaminant in food and animal feed, which is a serious hazard to human and animal health. An anti-DAS mAb, 3H10, with high sensitivity and specificity, was prepared, and an indirect competitive enzyme-linked immunosorbent assay (ic-ELISA) and a lateral-flow immunochromatographic strip (ICA strip) were developed for rapid testing of DAS in rice samples. The 50% inhibitory concentration and limit of detection of ic-ELISA were 5.97 and 0.78 ng/mL, respectively. The recovery of rice samples ranged from 99.4 to 110.7%, demonstrating that the analytical method can be used to detect rice samples. The cutoff value of the lateral-flow ICA strip to DAS was 500 ng/g. The developed immunoassay method can provide an effective method of initially detecting and screening DAS in food and feed samples.

Sensitive Immunochromatographic Assay Using Highly Luminescent Quantum Dot Nanobeads as Tracer for the Detection of Cyproheptadine Hydrochloride in Animal-Derived Food

Cyproheptadine hydrochloride (CYP), used as human and veterinary drug, has been used illegally as feed additive for food-producing animals, which could remain in food and jeopardize human health. There is a need for on-site detection of CYP residue in animal-derived food. In this study, a hapten was designed, and a specific monoclonal antibody (mAb) was developed to detect CYP with an IC50 of 1.38 ng/mL and negligible cross-reactivity (CR) for other analogs. Forthermore, a high sensitive immunochromatographic assay (QBs-ICA) was developed using quantum dot nanobeads as reporters. The assay showed the linear detection range (IC20-IC80) of 0.03-0.52 ng/mL, the limit of detection (LOD) and visual detection limit (VDL) reached to 0.01 and 0.625 ng/mL, respectively. Spiked recovery study in pig urine and pork confirmed that the QBs-ICA was applicable for on-site testing. This assay showed better sensitivity and speedy than the reported instrumental analysis and immunoassays.

Electro-spinning fabrication of nitrogen, phosphorus co-doped porous carbon nanofiber as an electro-chemiluminescent sensor for the determination of cyproheptadine

Nitrogen, phosphorus co-doped porous carbon nanofiber (N, P-PCNF) is prepared by electrospinning the mixed solution of polyacrylonitrile (PAN), polyvinylpyrrolidone (PVP) and phosphoric acid followed by carbonization. The N, P-PCNF as a modified electrode material is directly used to fabricate an electro-chemiluminescent sensor for determination of cyproheptadine, and owing to the large specific area, more active sites and promotion of electron transfer, the sensor exhibits high electro-catalytic activity, high sensitivity, a good linear relationship ranging from 1.0 × 10-7 to 1.0 × 10-5 mol L-1 and a low detection limit (2.89 × 10-8 mol L-1). In addition, the good recoveries indicate that the sensor is a promising device for the detection of cyproheptadine in real samples.