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Measure binding kinetics directly in serum, plasma, and CSF

Crude matrices contain proteins and lipids that can cause non-specific binding. An antifouling hydrogel minimises these interactions, enabling real time affinity, kinetics, and active concentration directly in the sample with minimal prep using only a 0.22 µm filter.
Antifouling surface for serum, plasma, and CSF
30 µL is enough for a measurement
Sensitive detection at 0.1 RU RMS baseline noise

Where label-free helps in bioanalysis of complex matrices

Binding measured directly in serum, plasma, CSF, or urine, with no tag on either partner.

Biomarker and cytokine quantification

Measure a biomarker or cytokine in patient serum or plasma and confirm real binding signal.

Concentration and binding behaviour read from the same trace.

active concentration

Drug concentration and PK/PD work

Measure drug–target binding directly in complex samples, from preclinical PK/PD and animal studies through to human samples.

One chip runs the full sample series, keeping early and late samples comparable.

kon, koff regenerable chip

Immunogenicity & anti-drug antibodies

Characterise an ADA response as kinetics, not only as titre.

Measured in the matrix the sample arrived in, with no tag on either partner.

ADA kinetics

Studies with limited sample material

Run a target with its controls and related markers from one small sample, in animal work, paediatric studies, or microsampling.

16 sensors on a single chip carry the panel, spotter required.

16 sensors

Diagnostic assay development

Screen capture reagents and surface chemistries against real matrix early.

Find out what holds up in matrix while the assay design can still change.

capture screening assay development

Don't see your application?

Discuss your assay with one of our application specialists.

Talk to a specialist

Benefits of the inQuiQ in complex biological matrices

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
In-flow immobilisation
Spotter immobilisation

Serum and plasma read as clean traces

An antifouling hydrogel layer limits adsorption of matrix proteins and lipids, and a reference channel carries what remains, so specific binding is separated from background.

gold surface
matrix adsorbs
the inQuiQ
antifouling hydrogel

bar length shows non-specific signal, not analyte response

antifouling hydrogelreferencing
what sticks, and what does not

The whole binding event, not one endpoint number

Endpoint methods report how much analyte is there at a fixed timepoint. The inQuiQ records association and dissociation as they happen, so rate, stability, and active concentration all come from the same trace.

kon, koff, KDactive concentration
four injections, or four endpoint numbers

Filter, inject, and the run is under way

Unpurified samples go straight in once they have passed a 0.22 µm filter, undiluted or diluted.

  • No extraction or cleanup step between the sample and the sensor
0.22 µm filter
straight from sample to sensor

From sample to sensorgram

Every measurement follows the same steps, whatever the matrix. A capture reagent is immobilised on the sensor, the filtered sample flows past, and the instrument records the response in real time. An endpoint assay gives you one number. The inQuiQ gives you the full curve.

Immobilisation

The capture reagent is attached to the sensor surface first.

Amine coupling or capture through a tag holds it in place on an antifouling hydrogel layer, which limits serum and plasma sticking to the surface. A reference channel without capture reagent runs alongside, so matrix background is subtracted from every injection.

  • amine coupling
  • capture
  • antifouling hydrogel

Deactivation

Unused activated sites are capped before the first sample arrives.

Without it the surface keeps reacting with whatever passes over, and in serum or plasma that puts matrix proteins and lipids in the trace instead of the pair being measured. The response then settles at the immobilised amount.

  • deactivation
  • blocking
  • non-specific binding

Association

The filtered sample flows across the surface and the response climbs.

Serum, plasma, CSF, or urine goes in undiluted or diluted, once past a 0.22 µm filter. Flow rate sets contact time, and injections up to 2 mL give a dilute analyte longer at the surface. The rising phase gives the on-rate, kon.

  • 0.22 µm filter
  • referencing
  • kon

Dissociation

Buffer replaces the sample and the response falls as the complex comes apart.

The dissociation phase gives the off-rate, koff, and 1/koff is residence time. A concentration series yields kon, koff, and KD in the matrix the sample arrived in. For an ADA response or a drug-target pair, that is the difference between a titre and a kinetic profile, and the reading is active concentration rather than total mass.

  • residence time
  • koff
  • KD
  • active concentration

Regeneration

A regeneration buffer strips what remains and returns the sensor to baseline.

The immobilised capture reagent stays in place, so every sample meets the same surface. Inject, read, regenerate, repeat, unattended. Every sensor on the chip reads each injection, so one small sample can cover a marker panel, or a target with its mismatch and off-target controls.

  • regeneration
  • automated cycling
  • off-target controls
Response (RU) Time

What the inQuiQ does for work in complex matrices

Six capabilities, one modular benchtop instrument, no label on either binding partner.

Clean signal from dirty samples

An antifouling hydrogel layer limits non-specific binding, so serum, plasma, and CSF can be measured without extensive cleanup.

antifouling hydrogel serum, plasma, CSF

Real-time ADA and PK-style data

Full on and off rates in matrix, so immunogenicity and drug binding are characterised as kinetic profiles rather than single endpoint values.

kon, koff, KD

Active concentration, not total mass

Binding activity is measured directly, which separates functional analyte from material that is present but not working.

active concentration

Consistent results across a study series

Run toxicology, animal efficacy, and human samples on the same regenerable chip and under consistent conditions, keeping results comparable across the programme.

2×384 wells regenerable chip

Stable baseline across long sample series

Drift stays typically below 0.3 RU per minute, so a full plate of study samples reads against the same reference.

< 0.3 RU/min drift

A target and its controls from one small sample

30 µL is enough for a measurement, and with a spotter 16 sensors carry a biomarker panel, or a target plus its specificity controls, on one chip.

30 µL minimum 16 sensors (spotter required)
Start A conversation

Talk to an application scientist

Bring us a matrix that has been giving you trouble. We will look at the assay design with you.

Ready to see the inQuiQ in action?

Questions researchers ask

Immobilise a capture reagent on an antifouling sensor surface, then inject filtered serum and follow binding in real time. The antifouling hydrogel limits non-specific adsorption from matrix proteins and lipids. Reference channels correct for bulk effects, so the remaining signal reflects specific binding, giving KD, kon, and koff directly in serum.

Three things do most of the work: surface chemistry that resists adsorption, referencing against a control channel to subtract bulk and background effects, and filtering the sample through a 0.22 µm filter. The antifouling hydrogel layer on the inQuiQ chips handles the first, and the 4-channel chip supports the second.

MSD is an endpoint electrochemiluminescence method: it reports how much ADA is present at one timepoint, with a tag on the detection reagent. Label-free measurement adds real-time association and dissociation with no tag, so an ADA response can be described by its kinetics and stability, not only its level.

No. Unpurified samples run directly once filtered through a 0.22 µm filter. Minimum sample volume is 30 µL, and up to 2 mL can be used when a low-concentration analyte needs longer contact time with the sensor surface.

The standard 4-channel photonic chip supports up to 4-plex with no extra hardware. With a microarray spotter, the chip carries 16 sensors, so a biomarker panel or a target plus mismatch and off-target controls can be read from a single small sample injection.