Targeting-ligand engagement
Confirm the particle reaches the receptor it was designed for.
Measure kon and koff at the particle surface.
receptor engagement
Lipid nanoparticle and extracellular vesicle characterisation
A particle can carry the right targeting ligand and still not engage its receptor. Size, heterogeneity, and a crowded surface make that hard to see in an endpoint assay. Label-free analysis reveals how these particles actually interact with their targets in real time.
Where EV and LNP researchers use label-free binding data
Label-free interaction analysis measures binding between unmodified molecules in real time. For EVs and LNPs it returns receptor engagement at the particle surface, association and dissociation rates, and specificity, with no dye or reporter added to the particle.
mRNA-LNP delivery
Characterise ionizable lipid formulations carrying nucleic acid cargo.
Compare formulations on receptor binding, alongside particle size.
ionizable lipid
EV surface markers
Profile exosome and microvesicle surface proteins.
Screen tetraspanins and other markers against one preparation.
tetraspanins
Protein corona
Follow what the particle picks up from its environment.
Measure serum protein binding, ApoE included, at the particle surface.
ApoE binding
Specificity and cross-reactivity
Separate on-target engagement from surface sticking.
Run competitive and blocking injections against control receptors.
receptor blocking
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Discuss your assay with one of our application specialists.
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Benefits of the inQuiQ in EV and LNP analysis
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
Measure engagement at the particle surface
The immobilised receptor captures the intact particle, measuring target engagement within the 100 nm sensing area at the sensor surface, not a lysate or released component.
kon, koff, KDtargeting ligand
particle engaging the receptor
Give a large particle time to reach the surface
EVs and LNPs diffuse slowly compared with a protein. Flow runs from 5 to 100 µL/min, up to 300 µL/min for low-viscosity samples, so contact time is set to the particle rather than to the instrument.
5 to 100 µL/minup to 300 µL/min
contact time set by flow rate
Confirm specific receptor engagement
Compare particle binding to an open target receptor, a blocked receptor, and control surfaces. A strong signal that drops when the receptor is blocked confirms specific engagement.
specificity controlscompetitive assays
target receptor:
available or blocked
available or blocked
How an EV binding run works
Every measurement follows the same steps, regardless of the type of particle. The ligand is immobilised on the sensor, the sample flows past, and the response is recorded through the whole injection.
Receptor immobilisation
The target receptor goes on the sensor surface first.
For lipid nanoparticle and extracellular vesicle characterisation the receptor, antibody, or surface marker is immobilised and the particle is injected over it. Density is kept low so large particles are not crowded on the surface.
- receptor capture
- surface marker
- ligand density
Deactivation
Unused activated sites are switched off before the first particle sample arrives.
Lipid surfaces bind readily to unblocked chemistry. Deactivation, together with the antifouling hydrogel, keeps the sensorgram to receptor engagement rather than particle sticking.
- deactivation
- antifouling
- non-specific binding
Association
The particle preparation flows across the surface and the response climbs.
In EV and LNP binding kinetics analysis the association phase gives kon for targeting-ligand engagement at the particle surface. Flow rate is lowered so slow-diffusing particles get enough contact time to reach the receptor.
- targeting ligand
- contact time
- kon
Dissociation
Buffer replaces the particle sample and the response falls as the complex comes apart.
The dissociation phase gives koff, and the pair gives KD for the particle and receptor. Competitive injections with free ligand then separate specific receptor engagement from cross-reactivity.
- koff
- KD
- receptor blocking
- cross-reactivity
Regeneration
A regeneration buffer returns the sensor to baseline for the next preparation.
The receptor stays in place, so every LNP formulation or EV batch meets the same surface across a characterisation series.
- regeneration
- formulation series
- automated cycling
Response (RU)
Time
What the inQuiQ does for EV and LNP research
Six capabilities, one modular benchtop instrument, in a label-free workflow.
Many receptors, one particle preparation
Four channels with in-flow immobilisation, or sixteen sensors with a spotter, put target receptors, control receptors, and blanks under the same injected sample.
16 sensors (spotter required)
30 µL
Sensitive to a small surface response
Baseline noise stays low enough that engagement by a heterogeneous particle population is still readable.
0.1 RU RMS
Weak engagement through tight binding
One affinity range covers loose corona interactions and high-affinity targeting-ligand engagement.
10 pM to 10 mM
Contact time set to the particle
EVs and LNPs diffuse slowly compared with a protein, and flow rate is what decides how long they meet the surface.
5 to 100 µL/min
up to 300 µL/min
Comparison across formulations
Lipid composition and ionic strength differ between formulations, and the same sensor surface carries the comparison across them.
formulation series
Modular system for an increased throughput
Simply add an autosampler, and run a long formulation or batch series unattended.
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 particle. 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
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 receptor and inject the LNP preparation over it. The association phase gives kon for targeting-ligand engagement, the dissociation phase gives koff, and the two give KD. Nothing is added to the particle, so the surface being measured is the one you formulated.
Spot capture antibodies against tetraspanins and other markers on one chip, then inject the vesicle preparation once. Every sensor reads the same injected sample in series, so a marker profile comes from a single run rather than one assay per marker.
Immobilise the serum protein of interest and inject the particle preparation, or run it the other way round. Real-time recording shows how quickly corona proteins associate and how long they stay, which an endpoint measurement of the settled corona cannot show.
EVs and LNPs diffuse far more slowly than a protein, so at high flow many particles pass without reaching the surface. Flow runs from 5 to 100 µL/min, up to 300 µL/min for low-viscosity samples, which lets contact time be set to the particle rather than to the instrument.
Run the injection over the target receptor, over a control receptor, and over a blank surface, then repeat with the receptor pre-blocked using free ligand. Binding that disappears when the receptor is blocked is receptor engagement; binding that stays is surface sticking.