Fragments
A fragment under 300 Da gives a small mass change and usually binds weakly.
Confirm that a fragment binds at all.
weak binders
Measure small molecule binding affinity and kinetics, label-free
Fragments, inhibitors, peptides. The inQuiQ resolves weak and short-lived binding in real time, on your own bench.
Label-free binding data across compound classes
Every compound class brings its own binding question. inQuiQ answers them from one platform.
Enzyme inhibitors
Separate potency from how long a compound stays bound.
Two inhibitors with the same IC50 can have very different off-rates.
koff, residence time
Agonists and antagonists
Full dose response at the target itself.
Binding and inhibition measured on the same surface, in the same run.
IC50, EC50
Allosteric modulators
Find out where on the target a compound acts.
Competitive assays show whether a compound shares the orthosteric site or sits elsewhere.
orthosteric vs allosteric
Peptides
Kinetics for peptide and protein pairs across chemistries.
No buffer constraints, so solvents, salts, and additives follow the assay rather than the instrument.
no buffer constraints
Don't see your compound class?
Discuss your assay with one of our application specialists.
Talk to a specialist
Benefits of the inQuiQ in small molecule research
01 / 04
One injection reads sixteen sensors.
Target, mutants, and counter-screen controls measured together, so a compound series moves as a batch instead of a queue.
*spotter necessary for 16-sensor immobilisation
30 µL minimumrun in series
four channels, sixteen sensors
A fragment-sized response still resolves.
Baseline noise stays low enough to read a small mass change, and flow rate sets how long the compound meets the target. Affinity runs from 10 pM to 10 mM, with steady-state fitting where dissociation is too fast for kinetics.
0.1 RU RMSkon, koff, KD
weak binder still resolves
Measure in native, label-free conditions.
The compound and its target meet unmodified, so nothing added to a small molecule changes the potency being measured.
- No tag on a compound where extra mass would alter binding
- Binding measured exactly as it happens in solution
the same binding event
See where the compound binds, not just how well.
Inject the test compound against a known site binder and watch the response. A compound competing for the same site blocks it. One binding elsewhere goes on alongside, in the same real-time trace.
competitive assaysIC50, EC50
blocked, or bound alongside
How an antibody binding run works
Every measurement follows the same steps, no matter the compound. The target is immobilised sensor, the compound flows past, and the instrument records the response in real time. An endpoint assay gives you one number. inQuiQ gives you the full curve.
Immobilisation
The target protein is attached to the sensor surface first.
Amine coupling or capture through a tag holds the protein in place. This target-on-the-surface setup is the standard configuration for fragment-based drug discovery and peptide screening, where the compound is injected as the analyte. Ligand density is set high enough that a low mass analyte still gives a readable response.
- amine coupling
- capture
- ligand density
Deactivation
Any activated site left unused is capped before the first compound arrives.
Without it the surface keeps reacting with whatever passes over, and non-specific binding shows up in the trace as signal that has nothing to do with the pair being measured. The response settles at a stable level, the immobilised amount.
- deactivation
- blocking
- non-specific binding
Association
The compound flows across the surface and the response climbs.
Sample and running buffer are matched, since a small solvent mismatch shifts the bulk signal more than the binding does, and a reference channel subtracts what remains. Flow between 1 and 100 µL/min sets contact time, up to 300 µL/min for low-viscosity samples. The rising phase gives the on-rate, kon.
- solvent matching
- referencing
- kon
Dissociation
Buffer replaces the sample and the response falls as the complex comes apart.
The falling phase gives the off-rate, koff, and 1/koff gives residence time. Fit a concentration series and you get kon, koff, and KD across 10 pM to 10 mM. Where dissociation is too fast to fit, the plateau of each injection gives steady-state affinity. Single-cycle kinetics runs the series uninterrupted when material is scarce.
- residence time
- koff
- KD
- steady state
- SCK
Regeneration
A regeneration buffer strips the remaining compound and returns the sensor to baseline, ready for the next injection.
The immobilised target stays in place, so every compound in a series meets the same surface. Inject, read, regenerate, repeat, unattended. Compounds run one after another, and each injection is read by every sensor on the chip, so one sample can cover several targets, mutants, or counter-screen controls at once.
- regeneration
- automated cycling
- saveable sequences
Response (RU)
Time
What inQuiQ does for small molecule and peptide research
Six capabilities, one modular benchtop instrument, no labels anywhere in the workflow.
Many targets, one small sample
Flexibly addressable channels for improved assay freedom, with 16 sensors to screen mutants, off-targets and controls efficiently.
16 sensors (spotter required)
30 µL
Resolve low mass binders
Baseline noise stays low enough that a fragment-sized mass change is still readable.
0.1 RU RMS
Cover weak binding through to optimised leads
One affinity range spans fragment hits and late-stage compounds, with steady-state fitting where kinetics run out.
10 pM to 10 mM
Confirm mechanism alongside potency
Competitive assays show whether two compounds share a site, and a dose response gives IC50 or EC50 on the same surface.
IC50
EC50
Add thermodynamic detail
The temperature-controlled flow cell runs a full temperature series.
temp. control from 16 to 40 °C
Modular system for an increased throughput
Simply add an autosampler, and increasy your throughput for library screens.
2×96 wells
2×384 wells
Application notes, publications, and data
From small molecule kinetics to antibody affinity, explore real binding data generated on inQuiQ. Each application note pairs a sensorgram with the affinity and kinetic values behind it.
Small Molecule Kinetics on inQuiQ
This white paper showcases the high sensitivity of ring resonator technology for measuring low-molecular-weight interactions, using Carbonic Anhydrase II (CAII) and two small-molecule binders as a model system.
APPLICATION NOTE
Antibody interaction analysis
Kinetic characterisation of antibodoes and whatnot
APPLICATION NOTE
Small molecule interactions
Ka and Kd for very tiny small biomolecules.
APPLICATION NOTE
Small molecule interactions
Ka and Kd for very tiny small biomolecules.
Start A conversation
See inQuiQ run your compound analysis
Tell us your target, your compound class, and the binding questions you need answered. We will show you inQuiQ on an assay close to yours.
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
info@deltalifescience.nl
Send us an email, and we will get back to you as soon as possible.
info@deltalifescience.nl
Send us an email, and we will get back to you as soon as possible.
Questions researchers ask
Immobilise the target protein on the sensor, then inject a concentration series of the compound. inQuiQ records association and dissociation in real time and fits the data to give affinity (KD) and kinetics (kon, koff) across a range of 10 pM to 10 mM. Weak binders are fitted at steady state instead.
Yes, as long as the sensor resolves the small mass change a fragment produces. inQuiQ runs at a baseline noise of 0.1 RU RMS, and ligand density is set high enough that a fragment under 300 Da gives a readable response. Weak binding is then fitted at steady state.
Residence time is the average time a compound stays bound, calculated as 1 divided by the off-rate (koff). inQuiQ measures koff directly from the dissociation phase in real time, so two compounds with the same IC50 can still be separated by how long each one holds its target.
Immobilise the protein partner and inject the peptide as a concentration series, or capture the peptide and flow the protein past. inQuiQ records association and dissociation in real time, returning kon, koff, and KD. There are no buffer constraints, so solvents and additives follow what the peptide needs.
The rule of 3 is a guideline for fragment libraries: molecular weight under 300 Da, no more than three hydrogen bond donors, no more than three acceptors, and a cLogP of three or less. Fragments this small bind weakly, so screening needs a method sensitive to a small mass change.