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BACKGROUND Ochratoxin A ( OTA) and zearalenone ( ZEN) are natural products of filamentous fungi that are harmful to humans and animals exposed to them even in extremely low concentration. The immunochromatographic test strip has become a popular diagnostic tool for detecting analytes. Its major advantages are that results can be obtained within 5-10 min, all needed reagents are included in the strip and it can be used to detect OTA and ZEN contamination in spots. In this study a colloidal gold-based immunochromatographic test strip of competitive format was developed for the rapid simultaneous qualitative and quantitative detection of OTA and ZEN in corn and other cereals. RESULTS The test strip results with the naked eye showed that the sensitivities were 6 µg kg−1 OTA and 20 µg kg−1 ZEN in cereal, while those with a TSR3000 membrane strip reader showed that the IC50 values of OTA and ZEN were 1.7905 and 4.3514 ng mL−1 and the lower detection limit ( LDL) values were 0.7697 and 1.2000 µg kg−1 respectively. These results were confirmed by high-performance liquid chromatography. CONCLUSION The immunochromatographic test strip developed in this study could be used for the rapid simultaneous, qualitative and quantitative screening of OTA and ZEN in corn samples. © 2015 Society of Chemical Industry [ABSTRACT FROM AUTHOR]

BACKGROUND: Nitroxynil (NIT) is a veterinary drug against hepatic fluke disease for food‐producing cattle and sheep. NIT has a long half‐life time in animals since it is highly bound to plasma protein. Therefore NIT possibly remains in animal edible tissues or milk due to drug abuse. In this study, a specific murine monoclonal antibody (mAb) against NIT was prepared and an immunochromatographic strip assay based on the mAb was developed for screening NIT in milk. RESULTS: The affinity constant of the anti‐NIT mAb was 2.93 × 1010 and the anti‐NIT mAb had almost no cross‐reactivity with other analogs, so that it showed good specificity. The cutoff value of this test strip was considered to be 50 ng mL−1 by the naked eye. When detected by the strip reader, the half maximum inhibition concentration (IC50) of the immunoassay strip was calculated to be 5.716 ng mL−1 and the limit of detection (LOD) was 1.146 ng mL−1. Intra‐assay recoveries from 88.80 to 97.13% were obtained, with the highest coefficient of variation (CV) at 9.01%; inter‐assay recoveries ranged from 84.60 to 106.87%, with the highest CV at 9.93%. CONCLUSION: The operative procedure of the proposed method can be completed within 10 min. The strip developed in this study was a practical tool for rapid semiquantitative and quantitative detection of NIT in milk. This study suggested great potential for analytically monitoring NIT in other food samples. © 2019 Society of Chemical Industry [ABSTRACT FROM AUTHOR]

Abstract: BACKGROUND: The importance of peptides in regulatory interactions has caused peptide‐protein docking to attract the attention of many researchers. A variety of methods for molecular modeling of peptide‐protein docking, such as local search and global search, are currently used. RESULTS: The interactions of 11 peptides and CSFV E2 protein were evaluated by the GalaxyPepDock and FlexX/ SYBYL programs, respectively. The assessment scores of all the peptides were correlated with their KD values. The final results showed that a moderate correlation coefficient was represented between KD values and CScores of predicted models by FlexX/ SYBYL. CONCLUSION: Our results demonstrate that considering the flexibility of the peptide is better than searching for more potential binding sites on the target protein surface while performing peptide‐protein molecular docking. These data provide reasonable evidence for the molecular design of peptides and guidance for the functional assignment of target proteins. © 2018 Society of Chemical Industry [ABSTRACT FROM AUTHOR]