Identification and characterization of target molecules utilizing Surface Plasmon Resonance (SPR)

In this joint project, the main emphasis of our work is on analyte-ligand and cell-analyte interactions and aimed to monitor cell cultures and fermentation processes using Surface Plasmon Resonance (SPR). Therefore, two model applications are investigated:

Cell cultures: Monitoring of secreted human serum albumin (HSA) to characterize the specific activity of in vitro cultivated human hepatocytes.
Fermentation processes: Monitoring of secreted cellulase to characterize the fermentation of Trichoderma viride.

Thereby, the design of the bioactive sensor surface is one of the most challenging aspects in SPR. The receptors (mostly antibodies) have to be immobilized in a functional, stable and possibly orientated way. Especially for measurements in crude samples, it is necessary to achieve a sufficient immobilization level and ensure high activity by avoiding steric hindrance. Furthermore, the surface has to be resistant to nonspecific binding of the sample components. To avoid false-positive results, a reference surface should also be examined. This is important to estimate all the factors that could produce a change in refractive index, like mechanical movements, fluctuations in temperature and nonspecific binding. Therefore, the reference surface should be as similar as possible to the sensing surface. Ideally, an unrelated antibody should be immobilized in the same way as the sensitive one. Signals arising from the reference antibody can then be subtracted from those arising from the sensitive antibody to obtain binding signals that only reflect the specific interaction.

SPR Sensorgram — The phases of a sensorgram. (I) Baseline with flow of buffer (signal of the functionalized gold surface). (II) Injection of the analyte (association). (III) End of injection and flow of buffer (dissociation). The receptors are presented in blue, the crosslinker in red, the analyte in orange and the blocking agent in green.

Project funding:

Financially supported by the European Union and the Free State of Saxony (SAB project UNILOC)

Project head:

Prof. Dr. Thomas Bley

Project staff:

Dipl.-Ing. Anja Henseleit
Phone.: +49 351 463 34272
Fax: +49 351 463 37761

Cooperation partner:

Gesellschaft für Silizium-Mikrosysteme mbH (GeSiM)
Bautzner Landstraße 45
01454 Großerkmannsdorf
Radeberger Präzisions- Formen und Werkzeugbau GmbH (KDS)
R.-Thieme-Straße 6
01900 Großröhrsdorf
Medizin- und Labortechnik Engineering GmbH (MLE)
Bernhard-Voß-Straße 27
01445 Radebeul
Schirmer + Dr. Berthold Umwelttechnik GmbH (SBU)
Andreas-Hecht-Straße 2
04736 Waldheim
Gesellschaft für Qualitätsmanagement und Statistik mbH (quo data)
Kaitzer Straße 135
01187 Dresden
Fraunhofer-Institut für Werkstoff- und Strahltechnik (IWS)
Winterbergstraße 28
01277 Dresden
Fraunhofer-Institut für Angewandte Optik und Feinmechanik (IOF)
Albert-Einstein-Straße 7
07745 Jena

Project term:

01.01.2012 - 30.06.2014

Contact:

Henseleit, Boschke, Bley