Objective: Traditional ochratoxin A(OTA) competitive antigen are high toxicity, high price and difficult preparation. Non-toxic and easy prepared OTA competitive antigen substitutes were expressed by recombinant filamentous phage which have OTA mimotope displayed on its p VI surface.
Methods: Recombinant phagemid pC89-COTA which contain OTA mimotope nucleotide sequence was constructed. Moreover, to increase the binding rate of OTA mimotope with antibody, Enterokinase cleavage sits were led into 5' terminal of OTA mimotope nucleotide sequence. The pC89-COTA was transformed into E. coli XL1-blue. The E. coli XL1-blue were infected by wild KM13 phage and recombinant phage with OTA mimotope displayed generated.
Results: OTA mimotope phage was successful expressed and OTA mimotope phage which digested by Enterokinase had significantly higher binding rate with antibody than phage which not digested by Enterokinase. Non-toxic OTA competitive ELISA was established by using this digested OTA mimotope phage, the detecting limitation was 100 microg/ml, the linear range of the inhibition curves was between 250 pg/ml and 1000 pg/ml. Spiked recoveries of the farina tritici blank samples, the recovery rate of OTA were 99.8% 112.3% and coefficients of variation were 8.19% 11.64%, then 16 commercially available samples were tested and the positive rate was 31.25%.
Conclusion: OTA mimotope phage were successfully expressed and non-toxic OTA competitive ELISA was established.
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Food Chem
February 2025
School of Food Science and Engineering, Hainan University, Haikou 570228, China. Electronic address:
Ochratoxin A (OTA) is a common food contaminant and poses a significant threat to human health, which requires rigorous monitoring. Mimotope peptides (MPs) are commonly used as non-toxic alternatives to toxic small molecules in eco-friendly immunoassays. Herein, with an anti-OTA nanobody as the target protein, cyclic 7-mer MPs of OTA were screened using phage display and immunomagnetic separation.
View Article and Find Full Text PDFBiosens Bioelectron
September 2024
School of Food Science and Engineering, Hainan University, Haikou 570228, China. Electronic address:
Rapid, portable, and accurate detection tools for monitoring ochratoxin A (OTA) in food are essential for the guarantee of food safety and human health. Herein, as a proof-of-concept, this study proposed a ratiometric bioluminescence immunosensor (RBL-immunosensor) for homogeneous detection of OTA in pepper. The construct of the RBL-immunosensor consists of three components, including the large fragment of the split nanoluciferase (NanoLuc)-tagged nanobody (NLg), the small fragment of the split NanoLuc-tagged mimotope peptide heptamer (MPSm), and the calibrator luciferase (GeNL).
View Article and Find Full Text PDFFood Chem
December 2023
School of Food Science and Engineering, Hainan University, Haikou 570228, China. Electronic address:
Mimotope-based immunoassays for mycotoxins eliminate the requirement for large amounts of mycotoxin standards for the chemosynthesis of artificial antigens. Herein, the nanobody-based magnetic beads were used to screen the mimotope (peptidomimetic) of ochratoxin A (OTA) from the phage-displayed peptide library. The interactions between nanobody and the most sensitive Y4 peptidomimetic were investigated by computer-assisted simulation and compared with those between nanobody and OTA.
View Article and Find Full Text PDFToxins (Basel)
December 2022
State Key Laboratory of Food Science and Technology, Nanchang University, Nanchang 330047, China.
"Point of care" (POC) methods without expensive instruments and special technicians are greatly needed for high-throughput analysis of mycotoxins. In comparison, the most widely used screening method of the conventional enzyme-linked immunosorbent assay (ELISA) confronts low sensitivity and harmful competing antigens. Herein, we develop a plasmonic-photothermal ELISA that allows precise readout by color-temperature dual-modal signals based on enzymatic reaction-induced AuNP aggregation for highly sensitive detection of ochratoxin A (OTA).
View Article and Find Full Text PDFToxins (Basel)
November 2021
State Key Laboratory of Food Science and Technology, Nanchang University, Nanchang 330047, China.
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