Bioanalytics – Group Jörg Hofmann

The Bioanalytics group established a Metabolomics technology platform and a Proteomics platform enabling the qualitative and quantitative analysis of biomolecules. This includes targeted and untargeted metabolite profiling. The Metabolomics branch consists of the following equipment:

Metabolomics platform

LC/MS-MS System

• ABI/MDS-Sciex QTRAP-3200 (Mass Spectrometer)
• Dionex ICS-3000 Ion Exchange HPLC (metabolite analysis)
• Dionex ULTIMATE-3000 HPLC (metabolite analysis)

Other instruments

• Dionex SUMMIT P680 HPLC (metabolite analysis)
• Shimadzu GCMS-QP2010S mit GC-2010 (Fatty acid analysis)
• Äkta Purifier HPLC (Protein purification)
• Pharmacia P-800 FPLC (low pressure LC)
• Packard Flow Scintillation Analyser (Radioactive molecules)
• BIO-TEK ELISA Multiwell microplate photometer (Vis fluorescence)
• Goebel UVIKON-XL Spectrophotometer (UV/Vis)

Access

Prior to use the analysis platform the requirements of our regulations   (PDF, german)  apply and a sample submission form which is available on request must be filled in and sent via e-mail to:   joerg.hofmann (at) fau.de

The core of our LC-MS/MS system represents the QTrap-3200 which is a versatile hybrid mass spectrometer. It combines the features of three cascaded mass filters (Triple-Quadrupole) needed for precise quantification with the concept of a linear iontrap enabling to derive information about quality (structure determination). This combination cares for an enhanced sensitivity. The Triple-Quadrupole together with other technical features (eg. N2-curtain) allows the analysis of relatively crude samples. For sensitive molecules we can adjust the harshness of ionisation by switching between different ion-sources ( Gas assisted Electro Spray Ionisation (ESI), Atmospheric pressure chemical ionisation (APCI) ). The ion source receives the stream of analytes after separation by the ICS-3000– ion chromatography- or the Ultimate-3000 HPLC system.
The inert ICS-3000 IC is exceptionally suited for ion exchange chromatography e.g. of carbohydrates or phosphorylated intermediates. It generates a “reagent-free” eluent required for mass spectrometry and has additional detectors (conductivity- and 3D amperometry detector) e.g. for the screening of sugars. In combination with the QTrap mass spectrometer we can use this device for targeted metabolite profiling with higher dynamic range and a broad spectrum of compounds.
Combining the Ultimate 3000 HPLC with an UV/Vis Photodiode Array Detector (PDA) results in a sophisticated 3D-visualization of fluorescence signals allowing easy identification and sensitve quantification of e.g. pigments, such as carotenoids or chlorophyll.
We have an additional HPLC system (Dionex SUMMIT) with a fluorescence detector suitable for the sensitive measurement of compounds like tocopherol and (derivatized) amino acids after Reversed Phase (RP) Chromatography.
We are also currently improving methods for GC/MS-based determination of fatty acids.
Our newly installed laboratory is further equipped with various supporting devices. Two types of absorption photometers are used to measure e.g. sugar concentration: 96-well ELISA Plate Readers with washer and fluorescence-detector facilitate quick simultaneous analyses of multiple samples. UV/Vis Spectrophotometers allow more sensitive absorption measurements.
In combination with our Flow Scintillation Analyser after chromatographic separation, we can detect radioactively labeled compounds. Furthermore we have installed a cold lab with an Äkta purifier and a low pressure FPLC sytem for the separation of proteins.
This equipment allows the parallel investigation of metabolites in complex mixtures and supports projects aimed at investigating plant-microbe interactions and primary plant metabolism ( AG S.Sonnewald, AG U.Sonnewald ). Furthermore, plant-cell-to-cell connections (plasmodesmata) are analysed at the biochemical and molecular level.

Proteomics platform