title: Rapid protein expression analysis with an interferometric biosensor for monitoring protein production.
abstract: The concentration of a recombinantly expressed protein has to be monitored to select optimal expression conditions throughout the protein production process. Today this is usually achieved semiquantitatively with sodium dodecyl sulfate polyacrylamide gel electrophoresis/western blotting or with ELISAs, which are time- and labor-intensive methods. In this paper the applicability of a label-free sensor system based on a Young interferometer is presented as an alternative for the monitoring of recombinant protein production. Once a protein is successfully produced, the interferometric biosensor allows any protein-protein interaction to be characterized in a label-free manner. This is demonstrated with an antibody/antigen pair, where the antibody is directed against a four-amino-acid tag used for protein expression analysis as well as purification during recombinant protein production. Label-free detection of the tagged protein is shown both in buffer and in bacterial cell lysate as a sample matrix. The system exhibiting a low limit of detection, low drift and reliable operation is compared with a commercial surface plasmon resonance sensor and a competitive ELISA.
authors.affiliation: Fraunhofer Institute for Physical Measurement Techniques, Heidenhofstr. 8, 79110 Freiburg, Germany. christian.hoffmann@iba-heiligenstadt.de
authors.forename: Christian
authors.initials: C
authors.lastname: Hoffmann
authors.forename: Katrin
authors.initials: K
authors.lastname: Schmitt
authors.forename: Albrecht
authors.initials: A
authors.lastname: Brandenburg
authors.forename: Steffen
authors.initials: S
authors.lastname: Hartmann
mesh_terms: D015374:Biosensing Techniques / Q000295:instrumentation* / Q000379:methods; D004797:Enzyme-Linked Immunosorbent Assay / Q000295:instrumentation* / Q000379:methods; D004867:Equipment Design; D019544:Equipment Failure Analysis; D020869:Gene Expression Profiling / Q000295:instrumentation* / Q000379:methods; D007368:Interferometry / Q000295:instrumentation* / Q000379:methods; D011994:Recombinant Proteins / Q000032:analysis*; D020349:Surface Plasmon Resonance / Q000295:instrumentation* / Q000379:methods
chemical_list: D011994:Recombinant Proteins