Upstream antibody titer measurement
Titer determination and IgG quantification through the bioreactor run.
Measure straight from clarified cell culture supernatant.
cell culture supernatant
Antibody titer, active concentration and host cell protein assay, on one label-free method
Titer, potency, a host cell protein assay and comparability are usually four assays on four platforms, each with its own standard curve and its own reagents, and none of them transfers cleanly to the next stage.
Where process and QC scientists use label-free binding analysis
Label-free interaction analysis measures real-time binding of unmodified molecules, enabling active concentration, binding kinetics, and batch-to-batch comparability without labels or secondary antibodies.
Clone and cell line selection
Rank clones on what they actually produce.
Cell line screening on titer and on binding activity across candidate lines.
clone selection
Downstream monitoring and host cell protein assay
Follow the product through capture and polishing.
Check binding activity and run HCP quantification after Protein A, ion exchange, and SEC.
quality control
Potency and protein concentration determination
Confirm identity, and that the product still engages its target.
Active concentration reports function, not total protein mass.
active concentration
Biosimilar comparability and batch release testing
Run candidate and reference standard on the same chip.
Compare ka, kd, and KD side by side across lots.
reference standard
Don't see your system?
Discuss your assay with one of our application specialists.
Talk to a specialist
Benefits of the inQuiQ in bioprocessing
01 / 04
One injection, four channels, sixteen sensors
Four independently addressable flow channels, each carrying four sensors, with the sample flowing through the channels in series.
30 µL minimumsequential flow paths
Run a plate of batches without touching it
The inQuiQ768 autosampler takes 2×96 or 2×384 well plates and injects one sample after another. Every batch meets the same surface under the same conditions.
2×96 wells2×384 wells
one plate, sequential injections
Measure what still binds, not just what is there
Total protein counts all protein. Reference standards convert binding to active concentration, showing only target-binding protein.
standard curvepotency
response read against a standard curve
Put the reference standard next to the lot
Immobilize reference material alongside candidate lots and inject once. Read up to 16 targets and controls from a single chip for direct comparability.
16 sensors (spotter required)
reference and lot, same axes
How label-free analysis works
Every measurement follows the same steps, whatever the stage. A capture ligand is held on the sensor, the sample flows past, and the response is recorded through the whole injection rather than at the end.
Ligand immobilization
The capture ligand goes on the sensor surface first.
For antibody titer and active concentration assays, Protein A, the antigen, or a receptor is coupled once and the same surface then serves every batch. Ligand density is set low enough that titer readings are not limited by transport to the surface.
- Protein A
- capture ligand
- ligand density
Deactivation
Unused activated sites are switched off before the first supernatant arrives.
Cell culture supernatant carries host cell protein and media components. Deactivation, together with the antifouling hydrogel, keeps those out of the sensorgram as non-specific binding.
- deactivation
- host cell protein
- non-specific binding
Association
The sample flows across the surface and the response climbs.
In bioprocessing kinetics analysis the association phase gives kon and, read against a standard curve, the active concentration of product in the sample. Supernatant is clarified through a 0.22 µm filter before injection.
- active concentration
- standard curve
- kon
Dissociation
Buffer replaces the sample and the response falls as the complex comes apart.
The dissociation phase gives koff, and kon with koff gives KD. Comparing those three numbers lot to lot is how potency, identity, and biosimilarity are tracked from upstream through release testing.
- koff
- KD
- potency
- comparability
Regeneration
A regeneration buffer returns the sensor to baseline for the next batch.
The capture ligand stays in place, so every lot and the reference standard meet the same surface. On the inQuiQ768 a full plate of batches runs unattended.
- regeneration
- reference standard
- unattended runs
Response (RU)
Time
What the inQuiQ does for bioprocessing
Six capabilities, one modular benchtop instrument, in a label-free workflow.
Many lots, one prepared surface
Four channels with in-flow immobilization, or sixteen sensors with a spotter, put batches and controls on the same capture surface.
16 sensors (spotter required)
30 µL
Active concentration, not total mass
A standard curve of the reference material turns binding response into the concentration of product that still engages its target.
standard curve
Clean signal from crude supernatant
The antifouling hydrogel limits non-specific binding, supporting host cell protein detection after 0.22 µm filtration.
0.22 µm filter
Reference standard side by side
Candidate lots and the reference material sit on one chip and meet the same injected sample, so comparability is read from one run.
biosimilarity
comparability
The same kinetic method at every stage
The measurement sits at-line, alongside process analytical technology rather than inside the process stream.
kon, koff, KD
Unattended runs on the inQuiQ768
The autosampler takes 2×96 or 2×384 well plates and works through them one injection after another.
2×96 wells
2×384 wells
Explore the inQuiQ768
Application notes, publications, and data
From small molecule kinetics to antibody affinity, explore real binding data generated on the inQuiQ. Each application note pairs a sensorgram with the affinity and kinetic values behind it.
Start A conversation
Talk to an application scientist
Bring your process step. We will tell you honestly whether label-free is the right method for it, and how the assay would be built.
Ready to see the inQuiQ in action?
Talk to an application scientist
Thirty minutes to discuss your assay design, before anyone mentions an instrument.
Download the inQuiQ brochure
Sensitivity, channel layout, footprint, and consumable formats in a couple of pages.
Delta Life Science
request@deltalifescience.nl
Send us an email, and we will get back to you as soon as possible.
request@deltalifescience.nl
Send us an email, and we will get back to you as soon as possible.
Questions researchers ask
Immobilize Protein A or the antigen on the sensor, inject clarified supernatant, and read the binding response against a standard curve of the reference material. An antibody titer assay run this way needs no secondary antibody and no label, and the result is the concentration of antibody that still binds rather than total protein mass.
Usually yes, after clarification through a 0.22 µm filter. The antifouling hydrogel surface limits binding by host cell protein and media components, and a reference channel subtracts what remains. That removes a purification step between the bioreactor and the number. The same chemistry runs the reverse experiment, a host cell protein assay that captures HCP on purpose for host cell protein quantification instead of excluding it.
Usually yes, after clarification through a 0.22 µm filter. The antifouling hydrogel surface limits binding by host cell protein and media components, and a reference channel subtracts what remains. That removes a purification step between the bioreactor and the number.
Put both on the same chip and inject the same sample series. Measuring kon, koff, and KD side by side under identical conditions makes the comparison a single experiment rather than two runs that have to be normalised against each other afterwards.
The inQuiQ768 autosampler holds 2×96 or 2×384 well plates and works through them one injection after another. Samples run in series, never in parallel, so every batch meets the same prepared surface under the same conditions across the sequence.
Not in the in-line sense. Process analytical technology usually means a probe in the stream, Raman or NIR spectroscopy with a multivariate model behind it, reporting continuously without a sample being taken. Label-free binding analysis is at-line: a sample is drawn, clarified through a 0.22 µm filter and injected. What it adds that an in-line probe cannot is a functional number, the concentration of product that still engages its target and the kinetics behind it, measured the same way at every stage. The two answer different questions and a process monitoring strategy can carry both.