Page 6 - Shimadzu Journal vol.9 Issue1

INSIGHT from CUSTOMER

Interview 1 Interview with Prof. Uwe Karst
“Cooperations always are

based on trust and on

personal relations”

Professor Karst, thank you very much for spending some time for this
interview. At first, could you introduce the outline of the research you
conduct in general?

Our group is specialized on the development and application of an­
alytical methods and instrumentation to address complex analyti­
cal problems, mainly originating from the biomedical area. One
of our major research areas is speciation analysis. The need for
speciation analysis is caused by the fact that the physio­
logical properties (uptake, distribution, metabolism and
excretion), of metal­containing compounds are strongly
dependent on the individual metal species rather than on
the heteroatom in general. This is easily proven using the
example that hexavalent chromium is considered to be
toxic and carcinogenic, while trivalent chromium is dis­
cussed as possible essential trace metal species. A second
major research area of our group is chemical imaging ­ the
analysis of the distribution and the spatially resolved quantifi­
cation of low molecular weight analytes in biological matrices.

How much are speciation analysis and (multimodal)
chemical imaging linked to each other?

Speciation analysis and chemical imaging complement
each other perfectly regarding the analysis of metal
species in the organism of humans, animals or plants.
Speciation analysis mostly uses liquid phase separa­
tions to separate the metal or metalloid species
prior to identification by electrospray mass spec­
trometry (ESI­MS) and quantification by inductively
coupled plasma­mass spectrometry (ICP­MS).
Chemical imaging, on the other hand, is carried
out by matrix­assisted laser desorption/ionization­
mass spectrometry (MALDI­MS) and related tech­
niques to obtain distribution information about
intact molecules, while distribution and quantification
of the elements is accessible by laser ablation (LA) cou­
pled to ICP­MS and micro­X­ray fluorescence (µXRF).
To provide an example, the investigation of side effects
of Cisplatin­based tumor therapy requires speciation

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