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5

Thermo Scientific Poster Note

PN64243-RAFA 0914S

wn screening workflows

ies of targeted screening

ere we show how one data

throughput quantitative

targeted investigations in a

r from different sources

out any further treatment. In

control sample and one

sample were run in the

e EQuan online SPE and

Port

lve

6-Port

Valve

Conventional

Volume

Sample Loop

12µmHypersilGold

Preconcentration

Column

ore RP-MS

calColumn

Accela1250 pump

Autosampler

Accela600

pump

6-Port

Valve

on and chromatographic

EQuan™ system was

0 µL was injected onto a

ld™ 20x2.1 mm trapping

n onto a Thermo Scientific

c column. A 6.7 minute

s shown in Fig 1. This

f 15 minutes for sample

and chromatographic

tion a Thermo Scientific

eter was used and run in full

IF) mode. In this mode full

ted with AIF fragmentation

0,000 (FWHM@

m/z

200)

range of

m/z

103 to 900

70 and resolution setting

ns) to be prepared for all

ass axis of the system was

As to be expected, it was possible to identify a good

number of contaminants, yielding a match on all three

confirming points. On the other it was clear that this way of

screening did not cover all possible compounds, as was

visible from the neat standard (as used normally for target

screening on these samples) measured in the same

batch. A clear benefit could be seen in the fact that

fragment information and library spectra were present for

additional confirmation (see Fig. 4).

In addition, a larger database with 2900 components was

applied still left open the question of contaminants not

found because they may not be members of this list

FIGURE 4. Three stages of confirmation in suspect

screen: isotope pattern match, fragment search and

library search; A: isotopic pattern overlay; B:

fragment overlay; C: Library comparison.

A

C

B

Unknown Screening

As a consequence of the limitations of a suspect screen

an unknown screening workflow was run. For this the

measured sequence was transferred to the screening

application SIEVE for unconditioned component

detection. Since all necessary settings and parameters

were transferred from TraceFinder to SIEVE

automatically, the component detection process could be

started immediately. As a result, 5000 components were

detected. Since such a list contains all components

regardless of their significance, refinement of this list was

clearly needed. As part of the process, all samples were

referenced against the tap water sample, so a simple filter

could be applied to remove matrix and background

signals from the result list, leaving 1829 components in

the list. Application of a principal component analysis to

this result revealed that three water samples were closely

related, while on water sample (surface water 1, see Fig.

5) seemed to be rather different in its content, so the filter

For confirmation and re

compound database wa

screening. The advanta

TraceFinder was to be a

suspect and unknown s

be able to use the same

It became visible that so

with higher amounts of

extract significant signal

maintaining full mass ac

intensity. Fig. 7 shows a

Loxoprofen, where the s

roughly the same intensi

signal of the compound.

resolved from the backg

compound can easily be

this clear separation of

high resolving power of

analysis.

FIGURE 7. Importance

unambiguous identific

monoisotopic signl (A)

are surrounded by ma

which are only separat

resolving power used.

Since all final processin

results of target, suspec

easily be combined into

and archiving one singl

between the two applica

shows a short selection

part of the initial target s

unknown screening pro

FIGURE 8. Selection o

present in previous ta

Compound Name Formula

m/z (Ap

Bisoprolol

C18H31NO4

326.23

Candesartan C24H20N6O3 441.16

Carbofuran

C12H15NO3

222.11

Dibenzylamine C14H15N

198.12

Irbesartan

C25H28N6O 429.24

Loxoprofen

C15H18O3

247.13

Mexacarbate C12H18N2O2 223.14

Oxazepam C15H11ClN2O2 287.05

Propiconazole C15H17Cl2N3O2 342.07

Tramadol

C16H25NO2

264.19

Conclusion