Mitsuo Ito

Separation of tetrodotoxin and paralytic shellfish poisons by high-performance liquid chromatography with a fluorometric detection using o-phthalaldehyde

Tetrodotoxin (TTX) and a variety of paralytic shellfish poisons (PSPs) were extracted from toxic specimens of puffer and scallop, and quantitated by high-performance liquid chromatography with a fluorometric detection using o-phthalaldehyde. Fluorescence spectra for the TTX- and PSP-fluorophors in 0.05 M borate buffer (pH 10) showed maxima at 453 nm with 332-nm excitation. The fluorescence intensity per nM of TTX was found to be 3 and those of PSP to be 4-12. This fluorometric technique may be useful for the simultaneous quantitation of TTX and PSP in small volumes of toxin extracts.

Low dead volume coulometric detector for liquid chromatography

Abstract A low dead volume coulometric detector flow cell for liquid chromatography was designed. Its cylindrical flow cell structure is simple and the cell volume is extremely small. The working and counter electrodes are made of bundled carbon fibres, and the working and counter electrode compartments are separated by a cation-exchange tube. The detector is applicable to many types of compounds. The detection limit for catecholamines is 0.05 pmol.

Correlative retention time peak identification method for glycated haemoglobin in high-performance liquid chromatography.

A convenient peak identification method in stepwise elution was investigated and correlation among the retention times of peaks in ion-exchange chromatography of glycated haemoglobin was assessed. By using a correlation method, accuracy of peak identification among columns with degradation and product deviations can be maintained. The correlative retention time identification procedure is treated theoretically.