Radiometric Assays for Kinase Activity

Radiometric Assays for Kinase Activity

Radiometric Assays for Kinase Activity


Creative BioMart offers high-quality services on kinase activity studies using radiometric assays to assist our customers in their kinase biology research and drug discovery. Our talented scientific team is able to provide our customers with unparalleled expertise and experience in kinase biology and pharmaceutical research.


Kinases capable of modifying target substrates by phosphorylation are the key mediator of messages in signaling pathways. Due to their critical role in many cellular processes, these enzymes are often under stringent control. Altering the activity of kinases may lead to changes in cellular response and the development of diseases. Therefore, these enzymes have been considered as potential therapeutic targets. It is of great interest to develop robust assays for monitoring their activities. Among different kinase assays that have been developed to detect the activity of specific kinases in cells, radiometric assays have long been considered the "gold standard" assay format.

Radiometric assays allow direct measurement of the rate of a given kinase reaction to accurately determine and quantify its catalytic activity. This assay format is versatile and compatible with virtually any type of kinase substrates, including peptides, proteins, small molecules, and lipids, as long as there is a suitable method to separate radiolabeled ATP and substrate. Radiometric assays for kinase activity can be performed in several different formats. SDS PAGE, filtration techniques, chromatography, or density gradient centrifugation are typically used to separate radiolabeled ATP from radiolabeled substrate in low-throughput assays, while Scintillation Proximity Assay (SPA) or FlashPlate assays can be used for high-throughput assays. Given the important role of kinases in cellular regulation, radiometric assays can be applied to almost any biological research that investigates enzymatic activity within cellular processes.

Radiometric kinase assay.

Figure 1. Radiometric kinase assay. (Duong-Ly K C & Peterson J R., 2016)

Options for Rediochemicals

Creative BioMart offers multiple options for radiochemicals to meet different labeling requirements.

Radiochemicals Specific Activity Radioactive Concentration Half Life

ATP, [γ-32P]

10 Ci/mmol
3000 Ci/mmol
6000 Ci/mmol

2 mCi/mL
10 mCi/mL
150 mCi/mL

14.3 days

ATP, [γ-33P]

3000 Ci/mmol

10 mCi/mL

25.4 days

ATP, [γ-35S]

25-100 Ci/mmol

10 mCi/mL

87.4 days

GTP, [γ-32P]

6000 Ci/mmol

10 mCi/mL

14.3 days

Featured Services

Creative BioMart offers different radiometric assay formats for measuring the activity of various types of kinases. Our scientists will work with you to develop an optimum assay and provide comprehensive results. If you can’t find an assay of your interest, please fill out the online inquiry form and let us know more details. We can offer you our expertise to help you accelerate your success.

In-Gel Kinase Assays

The in-gel kinase assay is a powerful method to direct measure the activity of specific kinases. Protein or peptide substrate embedded in polyacrylamide gels can be phosphorylated by kinases and then separated by electrophoresis under denaturing conditions. The fractionated samples are renatured in situ. The gel is incubated with ATP, [γ-32P] and the kinase activity can be visualized by autoradiography.

Radiometric Filtration Binding Assays

The radioisotope filtration binding assay allows for the detection of kinase phosphoryl transfer activity, which is proportional to the amount of phosphorylated substrate. This assay is the only format that directly detects the true product without any special substrate labeling or modification. Radiometric filtration binding assays is universal and can be used for all kinds of kinases.

SPA Kinase Assays

The scintillation proximity assay (SPA) using radioisotope-labeled ATP is an activity-based homogenous and versatile assay that allows for rapid and sensitive detection of kinase activity. SPA kinase assays have been developed for a variety of kinases such as serine/threonine, tyrosine, and histidine. This assay format does not require washing steps, making it HTS friendly.

Creative BioMart is an advanced biotech company within the field of kinase/phosphatase biology. We offer our expertise in establishing assays for kinase screening & profiling. We have state-of-the-art facilities and technology to provide efficient services with guaranteed turnaround times. A large collection of ready-to-use kinase activity assay kits are also available to help our customers save precious time. If you have any questions, please do not hesitate to contact us.


  • Duong-Ly K C & Peterson J R. A high-throughput radiometric kinase assay. Kinase Screening and Profiling. Humana Press, New York, NY, 2016: 87-95.
  • Jia Y, et al. Current in vitro kinase assay technologies: the quest for a universal format. Current drug discovery technologies, 2008, 5(1): 59-69.
For research use only. Not intended for any clinical use.