The Applied Analytical Chemistry working group deals with the analysis of complex samples. We are trying to set up a four-dimensional analysis platform in which multidimensional chromatography and the coupling of ion mobility and mass spectrometry are used in order to achieve maximum separation performance. We want to separate as many components of a sample (> 1,000) as possible on a column system on the basis of the functional groups and then generate a further separation with regard to the size and mass of the analytes so that we are able to analyze several 10,000 analytes in a sample within one hour.

Data evaluation of such complex samples represents an enormous challenge. For this reason, we are working on the development of a software-supported workflow. We are also using self-written programs based on Python and R. These programs are also used in our metabolome and lipidome analysis in the field of cancer research, where we collaborate with international and national researchers to better understand the metastasis of tumor cells, for example.

In addition, we are also interested in why some tumor cells are not killed by chemotherapy, whereas most other tumor cells die. To investigate this, we are developing a single-cell ion source with which it is possible, after coupling with a mass spectrometer, to analyze the metabolome of individual cells and determine the differences between the individual tumor cells.

Although mass spectrometric detection is very powerful, even the most expensive mass spectrometer in the world cannot distinguish glucose from fructose, as both substances, known as isobars, have the same molecular formula and differ only in their structure. In our experiments on the single-cell analysis of tumor cells, we cannot use chromatographic pre-separation, which means that we have no chance of analyzing isobaric substances in mass spectrometric detection. For this reason, we are also working on the coupling of ion mobility spectrometry (IMS) with mass spectrometry (MS). Here, the ions are separated according to size to charge with IMS and according to mass to charge with MS. And since isobaric substances do not differ in mass but in size or structure, the use of so-called ion mobility mass spectrometers (IM-MS) can often solve the problem of analyzing isobaric substances.

In order to transfer the analytes optimally into the MS or IM-MS, they must first be ionized in so-called ion sources. Depending on polarity, size, thermal stability and functional groups, different ion sources must be used for this purpose, all of which have advantages and disadvantages. This is why we are constantly developing new ion sources in search of the "jack of all trades", i.e. the ion source that can ionize all analytes well and has no significant disadvantages.

Get an overview of the analytical systems in the labs of our working group