Metabolic Activity Assays FAQ

Some assays tolerate multiple freeze/thaw cycles, while others do not. In general, avoid repeated freeze/thaw of reagents and aliquot reagents if needed.

Use white, opaque-walled plates to maximize signal reflection and sensitivity while minimizing crosstalk between wells. Always refer to the technical manual for specific plate recommendations. If your plate format differs from what is recommended, we suggest validating signal performance and consistency before use in critical experiments.

Choosing the right assay depends on your research goals, the metabolic pathway of interest, and your sample type. We offer assays for glucose uptake, lactate production, glutamine consumption, NAD(P)/NAD(P)H detection, and more—all compatible with a range of cell models, including adherent cells, suspension cells, 3D cultures and media samples. Explore our How to Measure Cellular Metabolism Guide for selection support and workflow examples.

Our metabolism assays produce luminescent signals that are directly proportional to metabolite levels or enzyme activity. You’ll receive quantitative data in relative light units (RLU) or concentration derived from a standard curve run with supplied standards, which can be analyzed using a standard luminometer or compatible plate reader. Most assays are endpoint-based with fast results, and protocols include guidance on data interpretation and normalization.

Multiple metabolites can be measured by splitting samples into parallel wells. All the assays use the same luminescent readout, so multiplexing in the same well is not possible. Multiplexing with other cell health readouts is possible in many cases and is demonstrated in our technical manuals. You should avoid overlapping detection signals (e.g., luminescence vs. fluorescence). Use controls to assess assay performance and contact our Technical Support Scientists if you have questions.

Yes. Our metabolism assays can help validate omics findings by providing functional confirmation of changes in gene expression, metabolite levels or pathway activity. For example, transcriptomics data indicating altered glycolysis can be supported by measuring lactate secretion or glucose consumption directly. These assays offer a scalable way to add confidence to high-throughput or discovery-stage datasets.

We know that the NAD/NADH-Glo™ Assay and the NADP/NADPH-Glo™ Assay have been cited for use in bacteria. Researchers used the NAD/NADH-Glo™ Assay to monitor how Listeria, Acinetobacter and Vibrio maintain redox balance under stress. The NADP/NADPH-Glo™ Assay was cited by researchers in studies of oxidative stress in Streptococcus and Campylobacter. Information on using these assays with bacteria can be obtained from these papers or by contacting our Technical Support Scientists. It may be possible to use other specific metabolite assays with bacteria. Our Technical Services Scientists can help with points to consider during your experiments. 

Yes, this is the concept behind our LDH-Glo™ Cytotoxicity Assay which derived from modifying the chemistry of the Lactate-Glo™ Assay. With excess lactate and no lactate dehydrogenase in the assay reagent, the light production is dependent upon how much lactate dehydrogenase is present in the test sample. We offer the plug-and-play Dehydrogenase-Glo™ Detection System for designing a custom dehydrogenase assay. You will need to supply the substrate of this dehydrogenase. Promega and Eppendorf collaborated to produce an Application Note which includes metabolic profile monitoring of human mesenchymal stem cells cultivated in a bioreactor. The Dehydrogenase-Glo™ Detection System was used to create assays for malate, isocitrate and 6-phosphogluconate dehydrogenases.

Most Promega metabolism assays are optimized for 96- and 384-well plates and can be adapted for high-throughput workflows. Their add-mix-read format is ideal for automation, and luminescent readouts are easily integrated into standard HTS platforms. For specific set-up recommendations, reach out to our Technical Support Scientists for assistance.

Yes, we have a system called the Metabolite-Glo™ Detection System which can be used to create a plug-and-play custom assay. You will need to supply a dehydrogenase specific to your metabolite and the metabolite to test and create a standard curve. This Application Note describes a protocol that used the Metabolite-Glo™ Detection System with commercially available isocitrate dehydrogenase and d-isocitrate.

Sample requests are available for many of our metabolism assays, though availability may vary by product and region. You can check current eligibility or request a sample by visiting the Metabolic Activity Assays page and selecting the assay of interest.

 We offer a few key resources to help researchers begin working with metabolism assays:

• Getting Started with Cellular Metabolism: Covers key concepts and experimental planning.
• How to Measure Cellular Metabolism: Provides assay selection guidance and workflow examples.
• How to Run a Metabolism Experiment: A three-minute overview video that covers assay setups, workflows and readout steps.

These resources are a great starting point for designing your experiment and our Technical Support Scientist are ready to help as well.