EI-FLEX, simplifying single-molecule spectroscopy

An affordable bench-top instrument capable of two-colour, single-molecule fluorescence detection in solution.

The EI-FLEX is a versatile tool for studying protein conformations and bimolecular interactions. Now smFRET and FCS experiments are accessible at your benchtop without optical tables or dark rooms.

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Real-time data analysis and visualisation.

Whether you're new to single-molecule experiments or an expert, our simple to use software provides you with the tools you need to generate publication-quality figures.

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EI-Cloud analysis

Democratising single-molecule biophysics

Dr Tim Craggs

Single molecule spectroscopy is a powerful technique that could lead to new discoveries in biophysics, life sciences, drug development and diagnostics. We set out to democratise this cutting-edge approach, and bring it to the widest possible user base. Ultimately we hope to make our instrument a standard tool in every biophysics lab.

Dr Tim Craggs

Founder, Exciting Instruments


  • Protein conformational landscapes

    Easily explore the full range of protein conformations present in solution and changes to their distribution induced by molecular interactions.

  • Verifying protein structure

    Verify that the static protein structures obtained from crystallography, cryoEM or AlphaFold are the major species present in the solution.

  • Binding and diffusion

    Investigate the binding and disassociation of biomolecular complexes, including protein-protein interactions, ligand-receptor binding (GPCRs) and Extracellular Vesicles (EVs).

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