A rapid purification procedure for tetrodotoxin derivatives by high-performance liquid chromatography

A simple procedure for purification of tetrodotoxin (TTX) derivatives by high-performance liquid chromatography is described. Chemically oxidized TTX, C₁₁-nortetrodotoxin (nor-TTX), was purified and collected by reverse-phase chromatography. The separation of nor-TTX from unreacted TTX was excellent and recovery of nor-TTX was more than 90%. The isolated nor-TTX was further coupled with lysine, and the coupled product was purified again by high-performance liquid chromatography on a cation-exchange column. The separation of all compounds required less than 15 min. The uv monitoring at 230 nm allowed the detection of TTX derivatives at the 2- to 3-ng level.