The BIACORE 2000 by Biacore AB is a biomolecular analyzer that utilizes surface plasmon resonance (SPR) technology to monitor biomolecular interactions in real time. SPR is a noninvasive optical measuring technique that does not require the labelling of interacting components. It is used to find the mass concentration of biomolecules that are adjacent to a specially prepared surface. Because the response is mostly independent of biomolecular nature, the same detection technique can be used across all investigations. The real time biomolecular interaction analysis (BIA) can detect surface protein concentrations as low as a few pg/mm2and can similarly measure differences in surface concentration as quick as a tenth of a second. In this way, the platform is able to determine binding specificity, kinetics, and concentration for analytes as small as 150 daltons and as large as 106daltons, making it incredibly flexible in application. Integrated fluidics and flow through technology provide maximum reproducibility in sample handling and makes kinetic calculations practical and intuitive.
The analysis of formation and dissociation events is performed on a sensor surface to which molecules are covalently bound. Investigations are made during continuous flow, with the sensor surface acting as one wall of the flow cell. Typically, the biospecific surface is reusable for multiple analyses in many applications, including protein and protein conjugate interaction studies as well as interactions of nucleic acids, lipid micelles, viruses, and cells. This versatility makes the BIACORE 2000 ideal for applications in drug discovery, monoclonal antibody production, and infectious disease research. Other uses of the real time BIA technology include measurement of kinetic constants (both rate and equilibrium), as well as kinetic ranking of related molecular species. Additionally, the system can be used to detect binding partners in screening applications and also to monitor enzymatic processes such as proteolysis, phosphorylation, nucleic acid synthesis, ligation, and cleavage. Analysis of multiple binding patterns is also possible, particularly where the ability of multiple analytes bound in sequence to a ligand may reveal both interference and cooperativity between said analytes. The technology can be utilized for concentration studies in which the biospecific surface acts as a selective probe that determines the concentration of a target substance in complex mixtures.
Because the detection technique of the BIACORE 2000 does not require labelling of the interacting components, ligand purification is not necessary for many of the aforementioned analytical processes. A key example of this is in kinetic ranking and epitope specificity studies, in which the experimental procedure can be performed for monoclonal antibodies in unfractionated hybridoma culture supernatant. For maximum flexibility and convenience, the unit can be preprogrammed for walkaway automated processing of nearly two hundred samples (two 96-well microplates simultaneously). The platform includes two pumps for liquid dispensing (one for constant flow and one for the autosampler), an autosampling mechanism, a detector, and microprocessors for comprehensive system control. It is a highly efficient and versatile detection instrument capable of providing precision and accuracy over a variety of applications.
Interaction analysis with SPR-MALDI interface.