Logo Universitat Bremen
Page path:

Molecular-isotopic Mass-Spectrometry

MAT 253

The ThermoFisher Scientific MAT 253 mass-spectrometer is equipped with a differential pumping system, an universal collector of 8 Faraday cups to measure isotopes of C, O, N, S and 2 dedicated Faraday cups to analyse HD. It uses 10 kV acceleration voltage and has 50 V amplifiers. It is connected to a ConFlo IV referencing interface. Our continuous-flow system is costumized with an oxygen bleed to reduce gas tailing in the ion source.

Inlet systems

Thermal-Conversion/Elemental-Analyser (TC/EA)

The TC/EA is equipped with autosamplers for liquid and solid samples. Samples are pyrolysed in a high-temperature reactor and the resulting H2 and CO gas is transferred via the ConFlo IV into the mass-spectrometer.
Typical uses include isotopic analyses of water (e.g., culture waters, precipitation, seawater) and isotopic determination of solid standards.
Typical precision is ≤ 2 ‰ for HD and ≤ 0.2 ‰ for 18O for liquid analyses and ≤ 3 ‰ for HD and ≤ 0.4 ‰ for 18O for solid analyses.

For questions please contact:

Dr. Enno Schefuß

Phone: 

+49 421 218-65526

Fax:

+49 421-218

Email:

Room: 

MARUM I, 1160

Gas-chromatograph for lipid analyses

This GC is our work-horse for compound-specific hydrogen isotope analyses. It is equipped with a programmable Triplus autosampler, two injectors (an automated on-column and a PTV injector) allowing most flexible sample injection techniques. After separation in the gas-chromatograph, the eluting compounds are pyrolysed to H2 gas by high-temperature conversion which is transferred into the mass-spectrometer via the ConFlo IV interface. the optional combustion reactor is not used in this system for easier maintenance (see below: ThermoFinnigan MAT 252).
Necessary sample amounts are 300 ng of compound per injection and typical precision is ≤ 3 ‰ for HD.

For questions please contact:

Dr. Enno Schefuß

Phone: 

+49 421 218-65526

Fax:

+49 421-218

Email:

Room: 

MARUM I, 1160

Gas-chromatograph for analyses of volatiles

This GC enables hydrogen and carbon isotope analysis of volatiles such as low-molecular weight hydrocarbons (e.g., methane) and carbon dioxide. It is equipped with a programmable TriPlus RSH autosampler. Depending on the isotopic signature to be determined, compounds separated in the gas-chromatograph are either pyrolysed to H2 by high-temperature conversion or converted to CO2 in a combustion reactor. These products are transferred into the mass-spectrometer via the ConFlo IV interface.

For questions please contact:

Dr. Thomas Pape

Phone: 

+49 421 218-65053

Fax:

+49 421 218-65099

Email:

Room: 

GEO, 1110

MAT 252

The ThermoFinnigan MAT 252 mass-spectrometer is equipped with an universal collector of 8 Faraday cups for the isotopic analyses of C, N, O, S. It uses 10 kV acceleration voltage and has 10 V amplifiers. The continuous-flow system is not equipped to analyse HD. It is connected to a modified GC/C III interface without reduction furnace.

Inlet systems

Gas-chromatograph for lipid analyses

The gas-chromatograph for lipid analyses is our work-horse for compound-specific 13C analyses and is equipped with a programmable Triplus autosampler and two injectors (automated on-column and large-volume split/splitless injector) allowing highly flexible sample injections. After separation in the gas-chromatograph, the compounds are combusted in a modified combustion reactor filled with Ni-wires and using an oxygen trickle-flow.
Typical precision for compound-specific 13C analyses is ≤ 0.3 ‰.

For questions please contact:

Dr. Enno Schefuß

Phone: 

+49 421 218-65526

Fax:

+49 421-218

Email:

Room: 

MARUM I, 1160

Laser-based systems

Picarro water analyser

The Cavity Ring-Down Spectrometer (CRDS) Picarro L-2130i is used for the simultaneous analysis of stable oxygen (d18O) and deuterium (dD) isotope signatures of water samples. The measurement is based on the absorption characteristic of water vapor isotopologues to a laser pulse that circulates in an evacuated chamber. The instrument is capable of handling ultra-small sample sizes (typically a few nL of water are required per injection) and is equipped with a combustion module to handle organic contamination in natural water samples.

For questions please contact:

Dr. Martin Kölling

Phone: 

+49 421 218-65111

Fax:

+49 421 218-9865111

Email:

Room: 

NW2-C / C 2340