First Detection of Tetrodotoxin in the Bivalve Paphies australis by Liquid Chromatography Coupled to Triple Quadrupole Mass Spectrometry With and Without Precolumn Reaction

Abstract

Two methods for the determination of tetrodotoxin (TTX) in marine biota have been developed and validated using ultra-performance LC coupled to triple quadrupole MS. The direct analysis of TTX is completed in one method, while the other method detects the dehydration product of TTX after reaction with base. The methods were validated in a single-laboratory trial and used to test Paphies australis (pipi) samples collected from Whangapoua, New Zealand during April 2011. Pa. australis is a commonly eaten species of bivalve that was found to contain TTX at levels up to 0.80 mg/kg in this study. The methods exhibited recoveries ranging from 94 to 120%, and the within laboratory reproducibility ranged from 6 to 27% for Pleurobranchaea maculata (grey-side gilled sea slug) and bivalve matrixes. Use of the method using a dehydration step showed no evidence of TTX analogs in any of the samples.

The association of bacterial C9-based TTX-like compounds with Prorocentrum minimum opens new uncertainties about shellfish seafood safety

“…These structures and molecular formula were also proposed as fragment ions of 5,6,11-trideoxyTTX21. In addition, a similar molecule C 9 H 9 N 3 O 2 , molecular weight 191.1, is produced after strong base treatment of TTX15. When the errors between theoretical and experimental data are compared some differences are observed.…”

“…Before 2014 only one highly toxic TTX-accumulation in scallops from Japan had been reported14. However, from 2014 to date three reports have identified the presence of TTX in shellfish and it was also detected in several edible gastropods1516172223. Therefore, the presence of TTXs in shellfish as well as the source of these toxins should be taken into account, since TTX-contaminated samples will not be detected by official analytical methods, such as LC-MS/MS or HLPC with fluorescence detection, because TTX is not required to be included in these methods.…”

“…This structure is common to all TTX active analogues21. In this sense the C9 base of TTX is often used to determine the total amount of TTX analogues in samples1516. However, the affinity and toxicity of analogues should be different2234.…”

“…To date, few appearances of TTX in bivalve molluscs have been reported1415. Recently, TTX has been detected in mussels and Pacific oyster from the English coast (2013–2014)16.…”

Study of the matrix effects of tetrodotoxin and its content in cooked seafood by liquid chromatography with triple quadrupole mass spectrometry

“…Therefore, sample dilution was performed to improve detection [47]. McNabb et al also reported a method of 1:400 or 1:10000 dilution for the quantitative determination of TTX in paphies australis [48]. In this study, the effect of the volume of the sample extract loaded into the MCX SPE cartridge was studied by measuring the % ME using the post-SPE standard spiking method.…”