Octet Data Analysis — Free Online BLI Analysis Tool

⚠️ Sensor-to-Sensor Variability

BLI biosensor tips can show variability in baseline levels and loading capacity between individual sensors in the same tray. This is more pronounced than chip-to-chip variability in SPR and can affect quantitative comparisons.

Solution: Pre-condition biosensors in buffer for 10+ minutes before the assay. Use reference sensors (unloaded tips or tips with no analyte) for subtraction. Normalize binding responses to ligand loading levels when comparing across sensors.

⚠️ Non-Specific Binding

Non-specific binding to the biosensor tip can appear as a slow, linear drift during the association phase that does not saturate. This is especially common with HIS1K and NTA sensors when working with complex samples or at high analyte concentrations.

Solution: Include reference sensors (no ligand loaded) to subtract non-specific binding. Add 0.1% BSA or 0.02% Tween-20 to your assay buffer. Consider switching biosensor type if NSB is persistent (e.g., SA with biotinylated ligand instead of HIS1K).

⚠️ Insufficient Shaking Speed

BLI uses orbital shaking to deliver analyte to the biosensor tip. If the shaking speed is too low, mass transport limitations can dominate — the observed k_a will be artificially slow, especially for fast-binding interactions.

Solution: Use 1000 rpm shaking speed for kinetic experiments (the standard recommendation from Sartorius). For very fast interactions (k_a > 10⁵ M⁻¹s⁻¹), even maximum shaking may not fully eliminate mass transport effects — consider SPR for these interactions.

⚠️ Ligand Leaching

If the baseline signal decreases during the assay (particularly with capture-based formats like AHC or Protein A), the ligand may be dissociating from the biosensor. This is called ligand leaching and leads to underestimation of k_a and overestimation of k_d.

Solution: Monitor baseline stability between cycles. For AHC sensors, ensure the captured antibody has sufficient affinity for the anti-human Fc surface. Consider covalent coupling (AR2G) for ligands that leach significantly from capture surfaces.

Can I analyze Octet data online?

Yes. KinetiHub runs entirely in your web browser. Upload your Octet .frd files and perform kinetic fitting without installing any software. KinetiHub parses the native Octet binary format, including step definitions, sensor assignments, and concentration metadata. Your data stays private unless you choose to share it.

What file format does KinetiHub accept for Octet data?

KinetiHub accepts native .frd files from Octet instruments. You can upload individual .frd files or ZIP the entire experiment folder. The .frd format contains all the raw data and metadata needed for analysis — no conversion or pre-processing required. Text exports from Octet Analysis Studio are also supported.

Which Octet models are compatible?

All current and legacy Octet models: RED96, RED96e, R8, R2, K2, HTX, QKe, and QK. The .frd format is consistent across the entire Octet product line, so data from any model works seamlessly with KinetiHub.

Does KinetiHub support all biosensor types?

Yes. KinetiHub supports data from all Octet biosensor types: SA, AHC, AR2G, HIS1K, NTA, Protein A, Protein G, FAB2G, AHQ, and custom sensors. The biosensor type is detected from the .frd metadata and displayed in the analysis interface. The kinetic fitting is independent of the surface chemistry — KinetiHub fits the observed binding traces regardless of how the ligand was immobilized.