An in vitro assay to detect Paralytic Shellfish Poison

摘要

We have developed an in vitro assay named Paralytic Shellfish Poison-test (PSP-test) that is capable of detecting low quantities of saxitoxin (STX), the first toxin studied from PSP. The PSP-test is an immunoassay based on the development of specific monoclonal antibodies (MAbs) capable of recognizing soluble saxitoxin (STX) and able to agglutinate in minutes, a latex containing STX adsorbed to its surface. The PSP-test is a two-step indirect immunoassay. During the first step, the MAbs are incubated with an extract suspected of containing STX. If the solution contains STX, this molecule will occupy the MAbs binding sites and block the latex agglutination. In the second step, MAbs-STX are incubated with an STX-latex. An inhibition indicates the presence of STX (PSP) in the sample. The PSP-test can detect within the range of 1.25-2.5 #mu#g/ml of STX standard. It is also capable of recognizing STX. in whole shellfish extract, acidic shellfish extract, and supernatants from aged toxic Cultures of bacteria or dinoflagellates. The assay is simple, economic, and quick. Training of in its use is fast and harmless to the user. It can be performed in the field as a first screening procedure because an instrument to interpret the results is not required.However, the PSP-test was not developed to replace the mouse bioassay but rather to be complementary, and the strategy used for its development can be easily adapted to other toxins.