Continuous vs. Endpoint Kinase Assays: What You Need to Know
Explore the key differences between continuous and endpoint kinase assays to determine the best approach for your research needs.
In drug discovery and biomedical research, Biochemical Kinase Activity Assays are vital tools used to study kinase function, explore signalling pathways, and screen for potential drug candidates that can inhibit or activate specific kinases. These assays are available in two major formats: continuous or endpoint. Both measure kinase activity, but they do so in different ways, each with its own set of advantages and limitations. In this blog, we’ll dive into the key differences between these assay types, helping you understand which is best suited for your research.
Endpoint Kinase Assays
Endpoint assays measure kinase activity at a specific time after the reaction starts. These assays work by incubating the kinase enzyme with its substrate for a specific period of time, after which the reaction is stopped, and the final amount of product (typically ADP or phosphorylated substrate) is measured at the "endpoint."
Continuous Kinase Assays
In contrast, continuous assays monitor kinase activity in real-time, providing a dynamic view of the enzymatic reaction as it progresses. Instead of stopping the reaction, continuous assays track the conversion of substrate to product continuously throughout the experiment.
Key Differences:
| Feature | Endpoint Assays | Continuous Assays |
|---|---|---|
| Reaction Monitoring | Snapshot of activity at a specific time point | Real-time, continuous monitoring throughout the reaction - generating a progress curve in every well. |
| Workflow Complexity | Multiple steps to generate signal. | Homogenous, add-and-read protocol streamlines benchwork. |
| Ideal For | Primary screening (HTS) and kinase selectivity profiling, where qualitative data is sufficient | Activity screening/profiling through lead optimization for in-depth inhibitor characterization. |
Which Assay Type Is Right for Your Research?
The choice between continuous and endpoint kinase assays depends on the goals of your research:
- Use Endpoint Assays if you need a simple, qualitative measure of kinase activity.
- Use Continuous Assays if you require detailed kinetic data, especially when developing covalent inhibitors.
At AssayQuant, we specialize in continuous kinase assays that provide unparalleled sensitivity and accuracy for monitoring enzyme activity in real-time.
Want to Learn More?
If you’re interested in exploring the advantages of continuous kinase assays or would like to see how our PhosphoSens-Kinetic Kinase Activity Assays can enhance your research, access our technote where we compare our PhosphoSens assay to a commonly used endpoint assay based on luminescent detection of ADP formation with two commercially available inhibitors of Epidermal Growth Factor Receptor (EGFR), Gefitinib and Osimertinib.
