13 / 20
Page 38
Notes:
allied
academies
J Clin Exp Tox 2017 | Volume 1 | Issue 2
Toxicology and Pharmacology
November 01-02, 2017 | Toronto, Canada
International Conference on
A high throughput targeted and non-targeted method for the analysis of microcystins and anatoxin-A
using on-line solid phase extraction coupled to liquid chromatography - quadrupole time-of-flight high
resolution mass spectrometry
Xavier Ortiz
Ontario Ministry of the Environment and Climate Change, Canada
M
icrocystins are cyclic heptapeptide hepatotoxins
produced by cyanobacteria in freshwater. Sample
preparation for the analysis of these cyanotoxins in water
from algal blooms can take up to several days due to the
matrix complexity and the low detection limits required
complying with current legislation. Moreover, there is a large
number of unknown microcystins that could potentially
exist in the environment resulting from different amino
acid substitutions into the microcystin skeletal structure.
To tackle these problems, the present study involved the
development of a high throughput method based on on-line
solid phase extraction coupled to liquid chromatography
that can provide quantitative results for 12 microcystin
variants (LR, YR, RR, HtyR, HilR, WR, LW, LA, LF, LY, Dha7-LR
and Dha7-RR) and anatoxin-A in less than three hours with
detection limits between 0.004-0.01 µgL-1 and uncertainty
between 4-14%. Data dependent acquisition was employed
for the non-targeted analysis of these cyanotoxins. Filtering
the data based on structure diagnostic fragments, two
unknown microcystin variants not previously reported in the
literature were detected. The structures Leu1-microcystin-
Met(O)R and Leu1-microcystin-LY were fully characterized by
accurate mass measurement, collision induced dissociation
and fragmentation prediction software.
Speaker Biography
Xavier Ortiz obtained his PhD degree at IQS-Barcelona (Spain), where he developed
methods for the analysis of Persistent Organic Pollutants in food using GC-HRMS
technology. Before coming to Canada, he worked in the pharmaceutical and
biotechnology private sectors as Analytical Lab Manager; characterizing, isolating
and purifying natural products from microalgae by preparative LC. Currently, he is a
Research Scientist at the Ontario Ministry of the Environment and Climate Change,
developing new methods for the analysis of emerging pollutants in the Canadian
Environment using chromatography and mass spectrometry. He is the Ministry’s Lead
Scientist in cyanotoxins analysis, specializing in lab automation to increase productivity
and non-targeted analysis of previously unknown toxins.
e:
xavier.ortiz@ontario.ca