You are studying the effects of a compound(s) on your cells. You want to know how the compound affects cell health over a period of hours, or even days. Real-time assays allow you to monitor cell viability, cytotoxicity and apoptosis continuously, to detect changes over time.
Why use a real-time assay?
A real-time assay enables you to repeatedly measure specific events or conditions over time from the same sample or plate well. Repeated measurement is possible because the cells are not harmed by real-time assay reagents. Real-time assays allow you to collect data without lysing the cells.
Advantages of Real-Time Measurement
Real-time assays allow you to:
- Detect kinetic changes during extended incubations, because cells remain viable when using a real-time cell viability assay. Traditional endpoint assays lyse cells in order to collect data, thus only allow sampling of cells at one time point.
- Perform an extended time study with a single plate, instead of the need to have a separate plate for each time point.
- Use less reagents. A single-plate assay uses fewer cells and plates, also less culture media and other cell culture tools than multiple plates.
- Multiplex your cell viability data with other assays to gain more data from a single plate well. Multiple assays from the same cells provides an internal control and less variability than working with multiple, replicate plates.
Here are some examples of data generated using real-time assays.
Real-Time Cell Viability
To measure cell viability in real time using a simple, plate-based, bioluminescent method, we used the RealTime-Glo™ MT Cell Viability Assay . RealTime-Glo™ determines the number of viable cells in culture by measuring the reducing potential of cells and thus metabolism. The nonlytic nature of this assay allows the cells to be used for additional downstream applications, including multiplexing with a variety of assay chemistries.
For more details on how the RealTime-Glo™ MT Cell Viability Assay works, watch this animation.
You can detect the accumulation of dead cells in culture via fluorescence, using a plate reader or microscope and the CellTox™ Green Cytotoxicity Assay. In the following figure, accumulation of dead cells was monitored over 72 hours.
Coming Soon: Real-Time Apoptosis Assays
We are preparing to roll out a new real-time , plate-reader based, apoptosis assay based on annexin V binding paired with NanoBiT® Technology. Stay tuned for more information on this new real-time apoptosis assay.
Are you using real-time assays for viability or cytotoxicity analysis? How would you use a real-time apoptosis assay? Tell us about the advantages you’ve gained using real-time assays in your research.