Anatoxin-a (VFDF), RBA 96 tests
Patented receptor-binding assay for the detection of Anatoxin-a in fresh water samples.
The Anatoxin-a Receptor-Binding Assay is a patented receptor-binding assay for the detection of Anatoxin-a in fresh water samples. This test is suitable for the quantitative and/or qualitative detection of Anatoxin-a. Positive samples should be confirmed by HPLC/MS, GC/MS, or other conventional methods. The test is a receptor-binding assay based on the affinity of Anatoxin-a for nicotinic acetylcholine receptors (nAChRs). Anatoxin-a, when present in a sample, will compete with the biotinylated alpha-bungarotoxin for the acetylcholine binding sites of nAChRs, from purified Torpedo electrocyte membranes, which were coated on the microtiter plate. After a washing step, a streptavidin-HRP solution is added to allow for the colorimetric detection of the biotinylated alpha-bungarotoxin bound on the receptor. After a second washing step, the substrate solution is added and a color signal is produced. The intensity of the blue color is inversely proportional to the concentration of Anatoxin-a present in the sample. The color reaction is stopped after a specified time and the color (yellow) is evaluated using a microplate photometer. The concentrations of the samples are determined by interpolation using the standard curve constructed with each run.