Development of an ic-ELISA and immunochromatographic strip based on IgG antibody for detection of ω-conotoxin MVIIA.

ω-conotoxin MVIIA(ω-CTX MVIIA) is a peptide consisting of 25 amino acid residues secreted mainly by Conus magus. In view of the toxin threat to humans and animals and defined application in analgesic therapy, it is necessary to develop a rapid, effective and accuracy method for the quantification and analysis of ω-CTX MVIIA in real samples. In the present study, a hybridoma cell named 2E5 stable secreting IgG antibody against ω-CTX MVIIA was selected successfully, and the subtype of Mab 2E5 was IgG1. The purified monoclonal antibody(Mab) 2E5 has high affinity (about 2.79 × 10 L/mol), and shows high specificity to ω-CTX MVIIA antigen. The linear range of ic-ELISA to detect ω-CTX MVIIA was 0.20˜7.22 μg/mL, with a lower detection limit (LOD) of 0.14 ng/mL. The average recovery of intra- and inter-assay were (85.45 ± 2.28)% and (88.03 ± 4.80)% respectively, with a coefficient of variation from 2.59% to 5.42%. The LOD of colloidal strip by naked eye was 1 μg/mL, and the detection time was less than 10 min without any equipment. The developed ELISA and colloidal test strips based on this IgG antibody could be used to detect ω-CTX MVIIA residue in real Conus samples.