Abstract: An artificial antigen of aflatoxin biosynthetic precursor Sterigmatocystin (ST) and a method for preparing same. Firstly, hydroxyacetic acid is reacted with the double bound of the difuran ring in the aflatoxin biosynthetic precursor ST, yielding an aflatoxin biosynthetic precursor ST hapten with an active carboxymethoxy group. Secondly, a carboxyl group on the ST hapten is attached to an amino group on a carrier protein. At last, the artificial antigen of aflatoxin biosynthetic precursor ST is obtained by dialysis and lyophilize.

Abstract: An aflatoxin nanobody immunoabsorbent and immunoaffinity column and preparation method and use thereof. The immunoabsorbent comprises a solid phase carrier and aflatoxin B1 nanobody 2014AFB-G15 coupled with the solid phase carrier. The 50% inhibiting concentration IC50 of aflatoxin B1 nanobody 2014AFB-G15 to aflatoxin B1 is 0.66 ng/mL, and the cross-reactivity of aflatoxin B1 nanobody 2014AFB-G15 to aflatoxins B2, G1, G2, and M1 are respectively 22.6%, 10.95%, 32.1% and 26%. The amino acid sequence of aflatoxin B1 nanobody 2014AFB-G15 is as depicted by SEQ ID NO: 7, and the coding gene sequence thereof is as depicted by SEQ ID NO: 8. The aflatoxin nanobody immunoaffinity column can be used for purification and concentration of sample extract prior to computer testing, and the immunoaffinity column can be reused repeatedly.

Abstract: An aflatoxin M1 nanobody, an immunosorbent and an immunoaffinity column. The aflatoxin M1 nanobody 2014AFM-G2 has the amino acid sequence of SEQ ID NO:7, is encoded by the nucleic acid sequence of SEQ ID NO:8, has a 50% inhibiting concentration IC50 to aflatoxin M1 of 0.208 ng/mL, and has cross reaction rates with aflatoxins B1, B2, G1, and G2 of 9.43%, 5.93%, 4.87% and 6.17%, respectively. The immunosorbent includes a solid phase carrier and aflatoxin M1 nanobody 2014AFM-G2 coupled with the solid phase carrier. The immunoaffinity column is loaded with the aflatoxin M1 nanobody immunosorbent. It can be used for purifying and concentrating an extracting solution of a sample before loading to a machine for detection and the immunoaffinity column can be used repeatedly for many times.

Abstract: A hybridoma cell line ST03 having China Center for Type Culture Collection (CCTCC) accession number C2013187, a monoclonal antibody against aflatoxin biosynthetic precursor ST produced by the hybridoma cell line ST03, and the use of the monoclonal antibody. The hybridoma cell line ST03 can be used for preparing a high-titer monoclonal antibody against aflatoxin biosynthetic precursor ST, and the titer of mouse ascites antibody against aflatoxin biosynthetic precursor ST determined by enzyme linked immunosorbent assay (ELISA) can reach 6.4×105. The monoclonal antibody against aflatoxin biosynthetic precursor ST has high sensitivity, has 50% inhibiting concentration IC50 to aflatoxin biosynthetic precursor ST of 0.36 ng/mL, has no cross reaction with all of aflatoxin B1, aflatoxin B2, aflatoxin G1, and aflatoxin G2, and can be used for the content determination of aflatoxin biosynthetic precursor ST.

Abstract: Aflatoxin M1 nanobody 2014AFM-G2 has the amino acid sequence of SEQ ID NO:7, and is encoded by the gene sequence of SEQ ID NO:8. The aflatoxin M1 nanobody 2014AFM-G2 obtained via screening has the properties of tolerance to organic reagents, tolerance to high temperature, tolerance to acids and bases and the like, and good stability. The aflatoxin M1 nanobody 2014AFM-G2 has 50% inhibiting concentration IC50 to aflatoxin M1 of 0.208 ng/mL, and has cross reaction rates with aflatoxin B1, B2, G1, G2 are 9.43%, 5.93%, 4.87% and 6.17%, respectively.

Abstract: Hybridoma cell line 10G4 and monoclonal antibody against total aflatoxins produced by the hybridoma cell line 10G4. The hybridoma cell line 10G4 is used to produce the monoclonal antibody that binds specifically total aflatoxin B1, B2, G1 and G2. The titer of the mouse ascites antibody produced by the 10G4 treated mouse is determined through non-competitive enzyme-linked immunosorbent assay and the titer can reach up to 5.12×105. The monoclonal antibody against total aflatoxin B1, B2, G1 and G2 are used for better identification of aflatoxin B1, B2, G1 and G2 with good consistency. The 50% inhibitory concentrations (IC50) of the antibody against aflatoxin B1, B2, G1 and G2 are 2.09 ng/mL, 2.23 ng/mL, 2.19 ng/mL and 3.21 ng/mL respectively. The range of cross reaction rate for aflatoxin B1, B2, G1 and G2 is about 65.2%-100%. The antibody is used for quantitative measurement of total aflatoxin B1, B2, G1 and G2.