EI-FLEX Pro
Transform molecular mechanisms and drug development workflows with single-molecule sensitivity
With our upgradable, automated single-molecule fluorescence spectroscopy system
For de-risking development rapid candidate selection ternary complex characterisation scaling your internal or CRO capabilities
For de-risking development rapid candidate selection ternary complex characterisation scaling your internal or CRO capabilities
Traditional biophysical characterisation often misses the rare conformations that lead to off-target effects or poor stability.
The EI-FLEX Pro offers an end-to-end, confocal benchtop system that rapidly reveals physiologically-relevant behaviour without immobilising targets or requiring large sample volumes, all at single-molecule precision.
This is ideal for validating PROTAC-induced ternary complexes, understanding conformational dynamics, characterising antibody-target engagement, or analysing protein aggregation with the quantitative precision of a specialist lab plus the ease required for modern pharmaceutical R&D.
Looking for our essential, cost-effective instrument the EI-FLEX? Find it here.
The Exciting Ecosystem: one stack from label design to discovery
Most instruments solve one step. We built a platform that connects all of them - so you spend less time stitching workflows together and more time doing science.
Choose where to label
Our tools and team help you identify optimal labelling positions - maximising signal without disrupting your molecule's native behaviour.
LABEL DESIGNExpress labelled constructs
From dye selection to conjugation strategy, we'll guide you through sample preparation.
SAMPLE PREPCapture every molecule
The EI-FLEX Pro does the heavy lifting. Confocal detection, automated acquisition, and real-time single-molecule sensitivity - all on your benchtop.
EI-FLEX PROAnalyse and publish
Integrated software takes you from raw photons to publication-ready figures. FRET histograms, FCS curves, burst analysis - no third-party tools required.
INTEGRATED SOFTWAREEvery step connects. When your label design, sample prep, instrument, and analysis all speak the same language, you get cleaner data, faster answers, and far fewer headaches.
Real-time single-molecule confidence
Resolve molecular heterogeneity early to ensure a more predictable path to the clinic.
Maximise lab ROI
Benchtop footprint with no darkrooms or specialist training required - plus sample to answer in less than a day.
Experimental design and demonstration
Guidance from world-class single-molecule experts and proof-of-concept sample runs.
Accelerate throughput
Seamless upgrade to high throughput acquisition (96 and 384 well plate formats).
Why labs choose the EI-FLEX Pro
Why labs choose the
EI-FLEX Pro
Key applications explorer
Select an application to discover how freely diffusing, single-molecule methods on the EI-FLEX Pro system can transform your workflows. View more applications here.
Trusted by Exciting researchers at










What our customers say
âIt has opened up new avenues of research because of the combined FCS, FCCS and single-molecule FRET capabilities. The high performance, stability and precision of the EI-FLEX instrument have really been a game-changer for experiments where sensitivity to picomolar concentration of biomolecules really matters.â
Dr. Steven Quinn, University of York
âSolution-based measurements, like those taken using the EI-FLEX, avoid surface tethering, which can introduce artefacts, especially for proteins that donât behave well near hydrophobic surfaces. Keeping proteins in solution lets you observe their native conformation, and itâs much easier experimentally: you label, dilute, and measure, often getting results in minutes rather than days or weeks with TIRF-based systems.
Associate Professor Kuang Shen, UMass Chan Medical School
âWhat sets the EI-FLEX apart is its versatility - it's our go-to for probing kinetics and conformational changes that the other systems can't resolve. This opens up a range of research for us that was previously impossible.â
Professor Edwin Antony, Saint Louis University
What our customers say
"What sets EI-FLEX apart is its versatility - it's our go-to for probing kinetics and conformational changes that the other systems can't fully resolve. This opens up a range of research for us that was previously impossible."
Dr. Steven Quinn, University of York
âSolution-based measurements, like those taken using the EI-FLEX, avoid surface tethering, which can introduce artefacts, especially for proteins that donât behave well near hydrophobic surfaces. Keeping proteins in solution lets you observe their native conformation, and itâs much easier experimentally: you label, dilute, and measure, often getting results in minutes rather than days or weeks with TIRF-based systems.
Associate Professor Kuang Shen, UMass Chan Medical School
"It has opened up new avenues of research because of the combined FCS, FCCS and single-molecule FRET capabilities. The high performance, stability and precision of the EI-FLEX instrument have really been a game-changer for experiments where sensitivity to picomolar concentration of biomolecules really matters."
Professor Edwin Antony, Saint Louis University
What our customers say
âIt has opened up new avenues of research because of the combined FCS, FCCS and single-molecule FRET capabilities. The high performance, stability and precision of the EI-FLEX instrument have really been a game-changer for experiments where sensitivity to picomolar concentration of biomolecules really matters.â
Dr. Steven Quinn, University of York
âSolution-based measurements, like those taken using the EI-FLEX, avoid surface tethering, which can introduce artefacts, especially for proteins that donât behave well near hydrophobic surfaces. Keeping proteins in solution lets you observe their native conformation, and itâs much easier experimentally: you label, dilute, and measure, often getting results in minutes rather than days or weeks with TIRF-based systems.
Associate Professor Kuang Shen, UMass Chan Medical School
âWhat sets the EI-FLEX apart is its versatility - it's our go-to for probing kinetics and conformational changes that the other systems can't resolve. This opens up a range of research for us that was previously impossible.â
Professor Edwin Antony, Saint Louis University