Easy to Use Instrument for Metabolic Assays, Some Weakness with Repeatability

The Seahorse XFp (and similar instruments for different plate sizes) can measure cellular metabolism with a variety of assay kits. In principle, cells are seeded in an 8-well plate and 4 test compounds can be sequentially injected into the well for calculating basal respiration, ATP production, proton leak, and maximal respiration. The main readouts measured are oxygen consumption rate (OCR) and extracellular acidification rate (ECAR). This system can provide great data on how specific metabolic pathways are impacted by addition of specific drugs such as for inhibiting particular components of the electron transport chain. However, there can be noticeable day-to-day variation when repeating experiments. Overall a decent platform for gaining some insight into metabolic flux, but other assays may be useful for confirming validity of observations.