The present invention relates to bioconjugates and labeled derivatives of anatoxin-a, at different positions of the molecule, suitable for producing antibodies with high affinity and specificity for anatoxin-a. At the same time, the present invention also relates to the use of bioconjugates of anatoxin‑a and labeled derivatives of anatoxin-a as assay antigens. Moreover, the present invention also relates to methods for analyzing, concentrating and extracting anatoxin-a using the antibodies obtained, sometimes together with assay antigens which are bioconjugates or labeled derivatives. This invention also provides a kit for analyzing anatoxin-a which comprises antibodies against this cyanotoxin sometimes together with assay antigens which are bioconjugates or labeled derivatives of anatoxin-a.