Bio-Layer Interferometry Services

Octet® R4 System

Rockland can help you select the best antibody or protein for your assay by providing label-free analysis using the Sartorius Octet® R4 System. Use it as part of your assay development program or as a stand-alone service.

Octet® Bio-Layer Interferometry

The label-free Bio-Layer Interferometry (BLI) technology enables the direct detection of specific proteins and other biomolecules in complex mixtures like crude cell culture supernatants and lysates. BLI uses optical-based biosensors to convert biological binding reactions into signals without the use of a detection label. This allows real-time monitoring of changes that occur when an analyte binds to a ligand immobilized on a biosensor surface and eliminates the need to manipulate individual assay components. The system can be used for a wide range of analyses including kinetic analysis, quantification of IgGs and other proteins, immunoassay development, epitope binning, and ligand binding assays.

Bio-Layer Interferometry


Kinetic Analysis

The Octet® R4 system allows the measurement of binding events in real-time to determine turn-on rates (ka), turn-off rates (kd) and affinity constants (KD).

Figure: Binding mode and kinetic analysis of Mouse Anti-HbS Antibody. Using Octet® R4, a series of nine (9) concentrations of Mouse Anti-HbS Antibody (3.0 nM-2.2 µM) were immobilized on an AR2G biosensor and exposed to 20 µg/ml HbS protein. Each colored curve represents the acquired signal of its antibody concentration. The interaction features reproducible duplicate injections and fits to a 1:2 bivalent kinetic model. The association constant (ka=32x103M-1s-1) and dissociation constant (kd=8.74x10-4s-1) values are depicted in the graph. The assay was performed as per the manufacture's protocol.

Protein Quantification

Faster and more accurate than ELISA, the Octet® R4 system directly measures the presence of specific proteins and other molecules in solution with minimal interference from complex matrices.

Figure: Fitting of kinetic data to bivalent binding site model. Steady-state signals (blue-filled symbols) are fitted to a bivalent binding site model (blue line). A 4-parameter non-linear regression curve fit was used for the integration of the data. The Mouse Anti-HbS Antibody presents a KD=27 nM (affinity constant) to HbS protein.

Sartorius Octet at Rockland

Octet® R4 System

Detection Technology Bio-Layer Interferometry (BLI)
Sample Type Proteins, antibodies, peptides, DNA, RNA, liposomes, viruses, and VLPs in various media including serum, buffers containing DMSO, periplasmic fractions, untreated cell culture supernatants, and crude cell lysates.
Information Provided Yes/No binding - Kinetic and affinity analysis (kobs, ka, kd, KD) - Specific and selective detection of molecules, even in crude samples - Relative and absolute quantitation of specific proteins in crude matrices or purified samples.
Number of Spectrometers 4
Maximum Simultaneous Reads 4
Sample Volume 180–220 µl/well, non-destructive testing
Plate Type 96-well
Orbital Flow Capacity Static or 100–1500 rpm
Analysis Temperature Range 15°C to 40°C, in 1°C increments