HTS Assay Development

With your project goals in mind, our scientists will develop the most promising screening assays for a successful hit identification campaign. We consider your desired mode of action (e.g., competitive, orthosteric, slow off-rate compounds) in our assay development. Enzyme (e.g., binding sites), substrate, and co-factors must be characterized to achieve in vitro conditions that will best represent the physiological reality.

As part of an HTS assay development campaign, we routinely perform the following:

  • Set-up of assays in a 384-well format:
    • Substrate screening for enzymatic assays
    • Ligand/Tracer screening for binding assays
    • Interaction partner screening for protein–protein interaction assay
  • Assay optimization:
    • Buffer optimization (pH, ionic strength, additives, redox systems, chelators, detergents)
    • Reaction parameter optimization (enzyme/substrate concentrations, incubation time, linearity, substrate KM determination, KD determination, KB determination of activator peptide)

Enzyme variation and kinetics of wild-type and dominant negative mutant

  • Assay miniaturization to 1,536-well format, automation, and robustness check:
    • Miniaturization/high-density format conversion
    • IC50 values of reference compounds
    • Stability of reagents (time dependence at room temperature/4°C), enzyme (freeze–thaw cycles), and signal (incubation until measurement)
    • Robustness of assay (RZ′, S/B, monitoring of plate edge effects)
    • Pre-screen of highly diverse in-house test library (10,000 compounds) for QC and to allow for determination of expected hit rate

Comparison of two readouts with our assay development test set

If you are interested in more details about our readout technologies or previous targets and possible mode-of-action assays, see


Publications from our NUVISAN team:

  • Examples can be found in our HTS publication list
  • Carettoni, D. & Bader, B. Assay development and high-throughput screening. Burger’s Medicinal Chemistry, Drug Discovery and Development, eighth edition 2021