The manual patch clamp method is able to detect fast responses allowing detection of very rapid changes in membrane potential. Comparing data generated using the FLIPR Membrane Potential Assay Kits with results from the manual patch clamp method shows good correlation (Figures 1 and 2). Both the opening and closing of the ion channel can be observed. This differs from DiBAC, which can only show unidirectional changes in membrane potential (Figure 3).
Comparison between patch clamp (mV) and FLIPR Membrane Potential (fluorescence) Assays on CHO cells expressing a voltage-gated K+ channel. Data courtesy of Michael Xie, Millenium Pharmaceuticals.