Highly Sensitive, Upgradeable System for Biomolecule Characterization

The Octet® R4 System Makes Biologics Development Affordable and Flexible

The 4-channel Octet® R4 instrument can be used for a wide range of analyses including kinetic analysis, titer of IgG and other proteins, reagent qualification, immunoassay development, bioprocess development, quality analysis, crude antibody screening, epitope binning/mapping, ligand binding assays, and small molecule analysis, elucidating cell signaling mechanisms, and infectious disease monitoring. Analysis can be done using a single to all four channels, enabling flexibility in sample throughput. 

The Octet® R4 System is priced for customers looking for a balance between throughput and cost. This system provides higher throughput than the 2-channel Octet® R2 instrument, and the same sensitivity as the 8-channel Octet® R8 instrument - at a lower overall price.  Contact us and we’ll help determine which throughput level is best for your lab and research needs.

The Benefits of the Octet® R4 Protein Analysis System

Fast Results

The Octet® R4 system has four parallel, independent channels for increased flexibility and faster results.

High Sensitivity, Moderate Throughput, Low Cost

The Octet® R4 system is designed for customers looking for moderate throughput sample analysis, without any compromise on assay sensitivity.

Reduced Assay Time and Maintenance Cost

The Octet® platform provides faster time to results and process economy when compared to other technologies due to its fluidics-free Dip and Read format. Additionally, crude sample compatibility saves valuable time by eliminating the need for sample pre-treatment, and non-destructive testing conserves precious samples for other assays.

Field Upgradeable within a Single Visit

Choose when to upgrade to an 8-channel Octet® system for higher throughput and full GMP compliance. Upgrades are performed on-site within a single visit by trained Sartorius engineers without the hassle of down time or system trade-in.

Sample Plate Cooling for Temperature-Sensitive Proteins

The sample plate temperature can be controlled from 15–40°C, which enables reliable kinetic determinations at different temperatures for temperature-sensitive proteins. Additional advantages of sample cooling include the ability to rapidly determine binding rate constants at multiple temperatures to extrapolate thermodynamic measurements. The Octet® R4 system’s four channels can be used independently to measure samples for screening purposes or in tandem, pairing the sample read with a dedicated reference for high-quality kinetic characterization.

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Kinetic and Affinity Characterization

The Octet® R4 system monitors binding events in real time to calculate on rates (ka), off rates (kd), and affinity constants (KD) by bringing the detection surface directly to the sample, eliminating the need for microfluidics. The sample plate temperature can be controlled from 15–40°C, which enables reliable kinetic determinations at different temperatures for temperature-sensitive proteins. Additional advantages of sample cooling include the ability to rapidly determine binding rate constants at multiple temperatures to extrapolate thermodynamic measurements.

Protein Quantitation in Bioprocessing

Accurately determining the concentration of antibodies and other proteins is critical to the selection of cell lines for development and the optimization of antibody production. The Octet® R4 system directly measures the presence of specific proteins and other molecules in solution with minimal interference from complex matrices with reproducible concentrations determined in as little as 2 minutes per sample using a simple, one-step assay. Rapid turnaround time of results improves process efficiencies and productivity that cannot be achieved with othermethods such as HPLC and ELISA.

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Featured Publications

Octet R Series System brochure cover

Brochure: Octet® R Series Systems

Accelerate your research with an upgradeable, label-free protein analysis platform

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Biomolecular Binding Kinetics Assays on the Octet® Platform thumbnail

Biomolecular Binding Kinetics Assays on the Octet® Platform

Introducing label-free platforms, the technology, capabilities, and advantages of label-free binding assessment in therapeutics development and...

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Writing Grant Proposals for Biomolecular Interactions Research

Grant writing can be a grind. You know how and why the funding is needed, but communicating that successfully sometimes seems like an art.

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Detection Technology

Bio-Layer Interferometry (BLI)

Biosensor Type

Disposable, single-use fiber optic biosensors with optional reuse by regeneration and/or re-racking in the biosensor tray

Data Presentation

Graphs displaying real-time kinetic binding sensorgrams, fitted result plots, and residuals of fits
Concentration data analysis including calibration curves and output of tabulated concentration data
Tabulated kinetic data
Epitope binning and cross-blocking matrices and trace overlays

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

Number of Spectrometers


Maximum Simultaneous Reads


Data Collection Rate

2, 5 or 10 Hz

Sample Position and Format

1 standard 96-well, black, flat-bottom microplate

Sample Volume

180–220 µL/well
Nondestructive testing

Orbital Flow Capacity

Static or 100–1500 rpm

Analysis Temperature Range

15°C to 40°C, in 1°C increments

Quantitation and Kinetics


Up to 4 assays in parallel

Molecular Weight Detection

>150 Da

Analysis Time per Sample

Real-time kinetic binding experiments from 5 minutes to 4 hours

Association Rate Constant (ka)101 to 107 M-1 s-1
Dissociation Rate Constant (kd)10-6 – 0.1 s-1
Affinity Constant (KD)

1 mM – 10 pM

Baseline Noise (RMS)

<3.0 pm

Baseline Drift

≤ 0.12 nm/hour

Quantitation Precision

CV <10%



72 lb (32.7 Kg)

Dimensions (H x W x D)

19.5 in x 22 in x 18.2 in
(49 cm x 56 cm x 46 cm)

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