Hydrophilic interaction liquid chromatography–electrospray ionization mass spectrometry of tetrodotoxin and its analogs

The advantages of ESI‐MS detection in conjunction with HILIC mode separations: Fundamentals and applications

“…Further, toxin profiles from different species were studied by using HILIC-ESI-MS alone or in combination with other methods. The Yotsu-Yamashita group was able to discover not only the distribution of tetrodotoxin, saxitoxin, and their analogs [142,143], but also the presence of a new dideoxy analog of tetrodotoxin [144] from puffer fish using only HILIC-ESI-MS. Similarly, Dell'Aversano et al [145] analyzed the assorted toxins produced by cyanobacteria.…”

Optimization of simultaneous analysis of tetrodotoxin, 4-epitetrodotoxin, 4,9-anhydrotetrodotoxin, and 5,6,11-trideoxytetrodotoxin by hydrophilic interaction liquid chromatography–tandem mass spectrometry

“…The lower limits of detection (signal-to-noise ratio = 3) with our instrument were 64 pg on-column for TTX, 128 pg for both 4-epiTTX and 4,9-anhydroTTX, and 180 pg for 5,6,11-trideoxyTTX. We previously reported that the lower limit of detection of TTX by LC-MS in the selected ion monitoring (SIM) mode was 192 pg on-column [11] using the same instrument as used in the present study. Optimization of detection conditions for MRM in the present study enhanced the sensitivity for TTX three times higher than that obtained by SIM of single-stage MS, but the sensitivity for 5,6,11-trideoxyTTX was almost the same as that by SIM.…”

“…TTXs were separated by HILC as reported previously [11,13,16]. Briefly, the LC system consisted of an LC-10AD pump (Shimadzu, Kyoto, Japan), a TSKgel Amide-80 column (150 9 2.0 mm i.d., particle size 5 lm, Tosoh, Tokyo, Japan), a vacuum degasser, and a Shimadzu SIL-HTA autosampler.…”

“…However, this ion pair reagent tended to remain in injection and ionization chambers of an LC-MS instrument and sometimes caused spectral noise. Such a problem was avoided in the second system by using hydrophilic interaction liquid chromatography (HILC) to separate TTX analogs without ion pair reagents [11]. Moreover, we also reported that almost all TTX analogs showed a [8].…”

“…Recently, liquid chromatography-mass spectrometry (LC-MS) has been recognized as a useful method to analyze TTX [8][9][10][11][12][13][14][15][16]. We previously reported two different systems to separate TTX analogs by LC-MS analysis.…”