Centre for Biological Signalling Studies

Protein Expression & Purification Facility

The Protein Expression and Purification Facility is one of the key units of the Toolbox, which is destined to help researchers as well as biotech and pharmaceutical companies to produce, purify and modify recombinant proteins.

Our unit provides infrastructure and expertise for following applications:

Protein expression and purification in bacterial, insect and mammalian cells:

  • Optimization of expression and purification protocols
  • Generation of stable lines for mammalian and insect cells
  • Scaling up production of proteins
  • Overexpression of multi-protein complexes
  • 15N and 15N/13C isotope labeling of proteins

Antibody production and purification from hybridoma cells:

  • Hybridoma cells maintaining
  • Antibody isotyping
  • Hybridoma cells subcloning
  • Labeling of antibody with fluorescent dye

Protein modifications:

  • Protein-Protein coupling
  • Protein-DNA coupling
  • Protein-dye coupling

Please fill out the Protein Service Request Form and send it per mail to


ÄKTA systems (GE)

A number of ÄKTA chromatography systems are available in Toolbox for separation and purification of biomolecules at scale ranging from micrograms to grams. The following instruments are located in the Signalhaus:

  • ÄKTAxpress
  • ÄKTAprime plus (x3)
  • ÄKTA Avant 25
  • ÄKTAexplorer (x2)

The ÄKTAexplorer and the ÄKTA Avant 25 are especially designed for fast automated media screening and method development. An integrated “design of experiments” functionality helps in obtaining the maximum information from a minimum number of experiments and an automated on-line buffer preparation enables easy screening for optimal buffer compositions and quick preparation of single buffers.


The ÄKTA Prime plus is a robust one-step purification system for routine repeat of optimized purification protocols, while the ÄKTAxpress allows to perform protocols with up to four successive chromatographic steps with minimal invested manpower.


Our ÄKTA systems are equipped with a broad range of chromatographic columns and media, which cover all main types of chromatographic techniques: size exclusion, cathion and anion exchange, affinity, hydrophobic interaction and immobilized-metal affinity (IMAC) chromatography.

Bioreactors and fermentor

Our facility has two bioreactors for culturing mammalian and insect cell lines Celligen310 (2.5 L and 14 L), which can be operated in batch, fed-batch and perfusion mode independently of each other or connected in series.

14 L sterilizable-in-place BioFlo415 Fermentor is a robust production scale system, designed to meet any research and production needs.

Up to 32 parameters could be controlled by BioCommand software, which allows very high cell density growth in bioreactors and fermentor.


HPLC Flexar (Perkin Elmar)

This ultra HPLC machine is a reliable system designed to provide fast analytical separations with highest sensitivity and highest resolution..

The modules available in our laboratory include:

  • an automated sampler
  • UV/Vis detector
  • refractive index detector.

CyFlow Cube cell sorter (Partec)


  • Closed piezo-driven sorter system
  • Non-destructive cell sorting
  • For sterile sorting and non-hazardous sorting
  • High purity sorting
  • Sorting channels: GFP, PE, APC

GALLIOS flow cytometer (Beckman-Coulter)

The GALLIOS flow cytometer is equipped with three laser lines (488nm Blue, 638nm Red and 405nm Violet) and can detect simultaneously up to 10 colors. 32 samples can be measured in automated acquisition mode using multi carousel loader.

A forward-scatter detector provides up to three measurements of cell size and visualization of particles down to 0.404 µm in diameter. Simultaneous measurements of integral, peak and width are available for all parameters, including scatter and fluorescence signals. A selection from up to 62 parameters can be processed per analysis, at acquisition rates of 25,000 events-per-second, with high yield.

RT-qPCR systems

qTower 2.2 (Analytic-Jena) and CFX384 Touch (Bio-Rad) RT-qPCR detection systems are precise, flexible and ease of use machines, which allow researchers to perform high-throughput real-time PCR analysis in a 96- or 384-well format.






Dr. Pavel Salavei


Schänzlestr. 18

79104 Freiburg