TY - JOUR

T1 - HPLC-HRMS quantification of the ichthyotoxin karmitoxin from Karlodinium armiger

AU - Andersen, Aaron John Christian

AU - de Medeiros, Lívia Soman

AU - Binzer, Sofie Bjørnholt

AU - Rasmussen, Silas Anselm

AU - Hansen, Per Juel

AU - Nielsen, Kristian Fog

AU - Jørgensen, Kevin

AU - Larsen, Thomas Ostenfeld

PY - 2017/9

Y1 - 2017/9

N2 - Being able to quantify ichthyotoxicmetabolites frommicroalgae allows for the determination of ecologically-relevant concentrations that can be simulated in laboratory experiments, as well as to investigate bioaccumulation and degradation. Here, the ichthyotoxin karmitoxin, produced by Karlodinium armiger, was quantified in laboratory-grown cultures using high-performance liquid chromatography (HPLC) coupled to electrospray ionisation high-resolution time-of-flight mass spectrometry (HRMS). Prior to the quantification of karmitoxin, a standard of karmitoxin was purified from K. armiger cultures (80 L). The standard was quantified by fluorescent derivatisation using Waters AccQ-Fluor reagent and derivatised fumonisin B1 and fumonisin B2 as standards, as each contain a primary amine. Various sample preparation methods for whole culture samples were assessed, including six different solid phase extraction substrates. During analysis of culture samples, MS source conditions were monitored with chloramphenicol and valinomycin as external standards over prolonged injection sequences (>12 h) and karmitoxin concentrations were determined using the response factor of a closely eluting iturin A2 internal standard. Using this method the limit of quantification was 0.11 µgmL-1, and the limit of detection was found to be 0.03 µg mL-1. Matrix effects were determined with the use of K. armiger cultures grown with 13C-labelled bicarbonate as the primary carbon source.

AB - Being able to quantify ichthyotoxicmetabolites frommicroalgae allows for the determination of ecologically-relevant concentrations that can be simulated in laboratory experiments, as well as to investigate bioaccumulation and degradation. Here, the ichthyotoxin karmitoxin, produced by Karlodinium armiger, was quantified in laboratory-grown cultures using high-performance liquid chromatography (HPLC) coupled to electrospray ionisation high-resolution time-of-flight mass spectrometry (HRMS). Prior to the quantification of karmitoxin, a standard of karmitoxin was purified from K. armiger cultures (80 L). The standard was quantified by fluorescent derivatisation using Waters AccQ-Fluor reagent and derivatised fumonisin B1 and fumonisin B2 as standards, as each contain a primary amine. Various sample preparation methods for whole culture samples were assessed, including six different solid phase extraction substrates. During analysis of culture samples, MS source conditions were monitored with chloramphenicol and valinomycin as external standards over prolonged injection sequences (>12 h) and karmitoxin concentrations were determined using the response factor of a closely eluting iturin A2 internal standard. Using this method the limit of quantification was 0.11 µgmL-1, and the limit of detection was found to be 0.03 µg mL-1. Matrix effects were determined with the use of K. armiger cultures grown with 13C-labelled bicarbonate as the primary carbon source.

U2 - 10.3390/md15090278

DO - 10.3390/md15090278

M3 - Journal article

C2 - 28858210

VL - 15

JO - Marine Drugs

JF - Marine Drugs

SN - 1660-3397

IS - 9

M1 - 278

ER -