Saxitoxin dihydrochloride

The mouse bioassay (MBA) was developed 70 years ago by Sommer and Meyer as part of their pioneering work that related the dinoflagellate Alexandrium catenella (Gonyaulax) as a causative agent of PSP (see Wekell et al ). At the time, the identity of the paralyzing toxic compounds was not known and the MBA remained for several years as a field test to help health officials manage toxic outbreaks in Alaska and British Columbia.Only after a purified saxitoxin dihydrochloride was made available in 1950 was it possible to calibrate the assay, and the AOAC accepted the new version of the MBA as an official method. Reasons for the sustained application of the MBA lie in its simplicity of application, relatively low cost, and availability of test protocols to calibrate mice strains to compare operator performance and to perform repeatability and reproducibility studies (National Shellfish Sanitation Program, USA ). 

Saxitoxin dihydrochloride CioHigCIjNjO, 35554-08-6 372.209 hyg wh solid vsHjO, MeOH, EtOH... 

Cl2H25CI2N7O5, Saxitoxin ethyl hemiketal dihydrochloride monohydrate, 41B, 647... 

Saxitoxin (1) was the first toxin brought to a pure form (20). The purification procedure was based upon the toxin s ability to bind tightly to weakly acidic resins. A single chromatography on a carboxylate resin such as Amberlite IRC-50 was capable of raising the specific toxicity of the extract several hundred times. Repeated chromatography on carboxylate resins and subsequent chromatography on acidic alumina afforded pure saxitoxin as an amorphous dihydrochloride. 

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