LC-MS Applications for Environmental Analysis

Thermo Scientific Poster Note

•

PN64243-RAFA 0914S

same sequence.

FIGURE 1. Schematics of the EQuan online SPE and

separation system.

6-Port

Valve

6-Port

Valve

Large

Volume

Sample

Loop

Conventional

Volume

Sample Loop

12µmHypersilGold

Preconcentration

Column

3µmAccucore RP-MS

18AnalyticalColumn

Accela1250 pump

Autosampler

Accela600

pump

6-Port

Valve

Liquid Chromatography

For online sample concentration and chromatographic

separation a Thermo Scientific EQuan™ system was

used. A sample volume of 1000 µL was injected onto a

Thermo Scientific Hypersil Gold™ 20

x 2.1 mm trapping

column with subsequent elution onto a Thermo Scientific

Accucore

RP-MS

18 analytic column. A 6.7 minute

solvent gradient was applied as shown in Fig 1. This

resulted in a total cycle time of 15 minutes for sample

injection, online concentration and chromatographic

separation.

Mass Spectrometry

For mass spectrometric detection a Thermo Scientific

Exactive Plus mass spectrometer was used and run in full

scan / all ion fragmentation (AIF) mode. In this mode full

scans are permanently alternated with AIF fragmentation

scans. A resolution setting of 70,000 (FWHM@

m/z

200)

was used (see Fig. 2). A mass range of

m/z

103 to 900

was applied (resp.

m/z

70 to 870 and resolution setting

35,000 FWHM for the AIF scans) to be prepared for all

possible contaminants. The mass axis of the system was

calibrated with the standard calibration mix once prior

measurement. Further optimization of the instrument

(compound tuning) was not required.

FIGURE 2. Exactive Plus method setup.

found because they ma

FIGURE 4. Three stage

screen: isotope patter

library search; A: isot

fragment overlay; C: L

Unknown Screening

As a consequence of th

an unknown screening

measured sequence wa

application SIEVE for u

detection. Since all nec

were transferred from Tr

automatically, the comp

started immediately. As

detected. Since such a l

regardless of their signif

clearly needed. As part

referenced against the t

could be applied to rem

signals from the result li

the list. Application of a

this result revealed that

related, while on water

5) seemed to be rather

for significant compone

FIGURE 5. PCA result

differences.

surfacewater4

surfacewater2