Agriculture Reference
In-Depth Information
throughput increase using conventional LC and QqLIT is automation and on-
line combination of the extraction procedure.
A relatively new, and extremely powerful, technique is Q-ToF-MS, where
a single quadrupole is combined with a time-of-flight (ToF) instrument. The
accurate mass measurement of the ToF-MS ensures a distinctly enhanced
selectivity compared with the other two types of tandem MS machines [105].
In one run, such multi-residue analysis can deal with more than 100
compounds with no loss of sensitivity.
Several examples have already been published with UPLC-TOF/MS
probably being one of the more powerful measurement tool available today
[141].
LC-MS
n
and LC-TOF/MS are powerful, complementary techniques that
can independently cover the majority of challenges related to the
determination of metabolites of food chemical contaminants. The sequential
combination of both systems benefits from their complementary advantages
and helps to increase the performance or simplify routine large scale methods
[142]. These two types of approaches are applied to control food safety—
MS/MS (QqQ or QqLIT) that give nominal masses information and either MS
or
MS/MS
(TOF,
QqTOF,
orbitrap)
able
to
obtain
accurate
mass
measurements [141].
The use of other types of high-resolution, accurate mass instruments (e.g.,
Orbitrap and Fourier transform ion cyclotron resonance, FT-ICR) has also
strongly emerged as attractive alternatives for these analyses. They are an
emerging trend within this field [145-146].
However, the extreme complexity and dynamic range of processed
samples, especially food samples, pose big challenges for identifying low-
abundance metabolites and degradation products. Identification of metabolites
and degradation products from food contaminants is an emerging and
challenging topic.
10.3 Nitrofurans
If there is a global challenge to determine nitrofuran residues from food it
would be unsuitable to ignore the latest analytical developments. It is now
becoming clear that recent developments can help to further reduce the
prevalence of nitrofuran residues and, at the same time, enable third countries
with a more limited analytical capacity to put in place a more realistic
monitoring strategy.
