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High-Resolution, Accurate-Mass Forensic Toxicology Screening in Blood Samples Using a Q Exactive Mass Spectrometer
ve High-Resolution,
nder 2.0 software. Identification of the
the precursor, the retention time, the
es.
mass accuracy. The method was set
of the parent and the retention time.
pattern and up to 5 fragment ions
ining up to 650 analytes was selected
f the results page showing the XIC
m reconstructed with 5 ppm mass
n confirmation (c).
FIGURE 4. Source Parameters
for HESI Probe.
Parameter
Value
Sheath Gas
30
Aux gas
15
Spray voltage (V)
3500
Capillary temp (
°
C)
320
Vaporizer Temp (
°
C)
350
FIGURE 5. ExactFinder results page showing XIC chromatogram for Diazepam
reconstructed with 5 ppm mass window (a), isotopic pattern (b) and fragment
ion confirmation (c).
Metabolite Identification
In addition to compound identification, it is possible to confirm the results by identifying
potential metabolites present in the sample. The approach is simple. As the acquisition
is performed in Full Scan mode, identification of metabolites can be realized with the
same HR-MS analysis by only extracting theroretical
m/z
values for predicted
biotransformations. Figure 6 shows an example of metabolites identified from a single
sample. The main compound identified is methadone and we have also been able to
identify two major metabolites: EDDP and EMDP.
* Parameters are the same for
positive and negative modes
(a)
(b)
(c)
FIGURE 7. List of analytes t
and confirmed using the 3 a
and Q Exactive screening.
Results are reported using flags of different colors :
•
(green circle): When the sample/compound/peak combination is identified
and fully confirmed.
•
(yellow triangle): When the sample/compound/peak combination is
identified but not fully confirmed.
•
(red square): When the sample/compound/peak combination is not
identified.
llision Energy (NCE) of 70. Relevant
s 3 and 4.
Waters Corporation, Milford, MA)
ns 612 molecules. Acquisition is
een used to acquire data in SRM
od includes 97 molecules.
FIGURE 6. ExactFinder results page showing XIC chromatogram for EDDP (a),
EMDP (b) and Methadone (c) reconstructed with 5 ppm mass window.
(a)
(b)
(c)
0
Alprazolam
Aminoclonazepam
Amiodarone
Amitriptyline
Amoxapine
Bromazepam
Benzoyecgonine
Citalopram
Cocaïne
Codeine
Cyamemazine
Desvenlafaxine
Diazepam
EDDP
Estazolam
Hydrocodone
Hydroxyzine
Ketamine
Levopromazine
Lormatazepam
Loxapine
Maprotiline
MDMA
Methadone
Mianserine
Mirtazapine
Morphine
Norcodeine
Nordiazepam
Oxazepam
Paracetamol
Promethazine
Propranolol
Quinine
Temazepam
THC
Tramadol
Venlafaxine
Zolpidem
Zopiclone
Nu
Nu
Nu