title: An optical biosensor for monitoring recombinant proteins in process media.
abstract: This paper describes the construction of a sensor for the direct monitoring of a recombinant protein, the human insulin analogue (MI3). The surface plasmon resonance (SPR) sensor incorporates an immobilised, sterilisable affinity-ligand that has been designed to bind to MI3. In practice, gold SPR devices were fabricated with; a 2D assembly of ethanethiol-modified ligand, a 2D mixed-assembly of ethanethiol-modified ligand and mercaptoethanol, a 3D coating of ligand-modified terminal-thiolated poly(vinyl)alcohol (PVA) or a 3D hydrogel of dextran coupled to a self-assembled monolayer (SAM) of mercaptohexaneundecanl-ol. Routine measurement of the concentration MI3 in the concentration range 1-100 mg/l in pilot-scale samples of crude fermentation broth have been achieved with high sensitivity levels and a high signal-to-noise ratio. Analysis can be achieved within < 10 min with the active surface being regenerable for at least 60 cycles over a 6 month period. The coupling of a robust, sterilisable and highly-selective sensor-coating with suitable transducer technologies promises to deliver sensors that are capable of direct in situ monitoring of biopharmaceuticals in industrial bioprocesses.
authors.affiliation: Institute of Biotechnology, University of Cambridge, UK. admin@biotech.cam.ac.uk
authors.forename: D M
authors.initials: DM
authors.lastname: Disley
authors.forename: P R
authors.initials: PR
authors.lastname: Morrill
authors.forename: K
authors.initials: K
authors.lastname: Sproule
authors.forename: C R
authors.initials: CR
authors.lastname: Lowe
mesh_terms: D001709:Biotechnology; D006046:Gold; D006801:Humans; D007328:Insulin / Q000031:analogs & derivatives / Q000032:analysis / Q000737:chemistry; D008024:Ligands; D008623:Mercaptoethanol; D008958:Models, Molecular; D055095:Optics and Photonics; D017433:Protein Structure, Secondary; D011994:Recombinant Proteins / Q000032:analysis* / Q000737:chemistry; D013438:Sulfhydryl Compounds; D020349:Surface Plasmon Resonance
chemical_list: D007328:Insulin; D008024:Ligands; D011994:Recombinant Proteins; D013438:Sulfhydryl Compounds; D008623:Mercaptoethanol; D006046:Gold; C007638:ethanethiol