Kinase Assays

With the largest portfolio of kinase assays available for drug discovery and 20 years of expertise in custom-tailored assay development, Reaction Biology is guaranteed to provide the in vitro kinase assay you need. 

Our kinase assays measure the effects of compounds on kinase activity. Kinase screening can be performed in low, medium, and high-throughput fashion. Our free choice setup allows clients to choose a part of kinases from our portfolio for testing any number of compounds. High-throughput kinase screening is available with cherry-picking, compound management, and IC50 follow-up options. 

  • Protein kinase assays are performed with gold standard radioactive assay formats to deliver reproducible high-quality data directly measuring enzyme activity, meaning you won't need to worry about false positives and negatives caused by other formats of detection. 
  • Kinase screening can be performed with ATP-competitive, substrate competitive, and allosteric inhibitors.
  • Many of our kinase assays are adaptable to any protein or peptide substrate without modification. 

Our radioactive kinase assays accurately measure enzyme activity. The kinase screening results of your test substance are provided as % of inhibition or IC50 value. Send us your test substance and we will provide comprehensive profiling and screening results.

Our contract research organization works with pharmaceutical and biotechnology companies as well as academic drug discovery teams from around the world who work with our global team of business development managers to coordinate their research needs with our kinase assay screening facilities

New Poster: Kinase drug discovery 20 years after imatinib

Reaction Biology sponsored a poster authored by Philip Cohen, Darren Cross, and Pasi Jänne that was published by Nature Reviews Drug Discovery.

The peer-reviewed poster illustrates the tremendous progress made over the last 20 years towards the development of new kinase inhibitors.

Download our Poster

RB Kinase Drug Discovery Poster

Browse our portfolio of biochemical kinase activity assays

See our complete list of kinase targets here.

Kinase Assay Details

Assay Formats

HotSpot™ and 33PanQinase™: two radioactive assay formats

Principle of radiometric kinase activity assay. 33 phosphate is transferred onto the substrate. The radioactive kinase substrate is than quantified

Reaction Biology offers two radioactive assay formats that are performed in our screening facilities located in Malvern, PA, USA, and Freiburg, Germany. Both assays are based on the transfer of 33P-labelled phosphate from ATP to the kinase substrate. The methods, however, differ with respect to retention and detection of the phosphorylated substrates. Proteins and peptides in the HotSpot™ assay (performed in the US) are captured via spotting of the reaction mix on a filter membrane. The 33PanQinase™ assay (performed in Germany) is performed with ScintiPlate microtiter plates, which are coated with scintillant for detection.

Lipid kinases are screened with ADP-Glo (Promega) at both facilities. 

Assay advantages

Radiometric assay formats are the gold standard for kinase screening producing reproducible, high-quality data, and directly measure enzyme activity. The catalytic product is directly detected (phosphorylated peptide or protein). False positives and negatives, as caused by indirect formats of detection, are avoided. 

Both, the HotSpotTM and 33PanQinaseTM assays allow detection of ATP- as well as substrate competitive and allosteric inhibitors.

HotSpot™ assays are adaptable to any protein or peptide substrate without modification. 

Screening at US facility

Setups: Single-dose screening in duplicates or IC50 value determination with 5 or 10 concentrations. Other screening formats are available upon request. 

The assay protocol for HotSpot™ Assay is available here.

ATP concentrations: 1 uM, 10 uM or apparent ATP-Km up to 100 uM

Controls: No inhibitor control (DMSO vehicle) and for every kinase, one kinase-specific control compound is tested in 10-dose IC50 format. 

Screening facility: Malvern, PA, USA

Turnaround time: 10 business days for standard projects. Expedited scheduling and data delivery can be arranged prior to the commencement of the studies. 

Report: The raw data, % enzyme activity and control compound IC50 values will be reported in Excel format for single-dose assays. For IC50 orders, raw data, IC50 values, and curve fitting will be delivered in Excel format. 
Assay conditions, target, and substrate information are available upon request. Requirements for this information should be noted prior to the commencement of the study.

Compound requirements: In brief, for a standard project with less than 50 kinases, 20ul of a 10mM DMSO stock or solid material is needed. Please inquire for compound requirements for large scale screening. Please refer to our FAQs for information regarding compound preparation and shipping.

Screening at German facility

Setup: Single-dose screening or IC50 value determination with 10 concentrations. Other screening formats are available upon request.

The assay protocol for 33PanQinase™ assay is available here.

ATP concentrations: apparent ATP-Km

Controls: DMSO only control; reference inhibitor control for IC50 value measurement

Screening facility: Freiburg, Germany

Turnaround time: 10 business days for standard projects. Expedited scheduling and data delivery can be arranged prior to commencement of the studies

Report: A detailed report will be provided including assay conditions, target, and substrate information. The raw data and % enzyme activity will be reported in Excel including IC50 values and curve fitting, if applicable. 

Compound requirements: In brief, for a standard project with less than 33 kinases, 100 µl of the stock solution with 100x of the highest assay concentration or solid material. Please inquire for compound requirements for large scale screening.

High-Throughput Screening

Library screening: Screen your own or our libraries. 

Available libraries:

  • Drug-like diversified small molecule libraries; > 110,000 compounds
  • Focused small libraries including kinase inhibitors, FDA-approved inhibitors, epigenetic inhibitors, natural products, and a clinical collection. 
  • Fragment libraries including a standard diversified fragment library, Fsp3-enriched fragments library, 3D fragment library, protein-protein interaction fragments, and covalent fragments library.

In addition to our high-throughput primary screening formats, we offer orthogonal screening formats and secondary screening formats. Hits can be characterized for their kinetic, binding affinity, mechanism of action, and intracellular activity. 

Our medicinal chemistry partners are available to optimize the structure-activity-relationship of your hits to increase potency and reduce off-target and toxic effects and enhance the pharmacological profile of your lead compounds. 

Assay Development

Kinase assays that are not part of our portfolio can be developed in a custom-tailored fashion. 

Our assay development service includes:

  • Plasmid construction, cDNA synthesis, and mutagenesis
  • E. coli or Baculovirus-based expression in Sf9 cells
  • Co-expression with co-factors is optional
  • Purification via HIS, GST, GST-HIS, HALO-HIS, SUMO-HIS, TXN-HIS or other tags via affinity chromatography
  • Tag cleavage and enzyme activation are optional 
  • Identification of suitable substrate 
  • Determination of enzyme activity
  • Optimization of assay conditions

View the Protein Production and Assay Development webpage here.