Characterization of human iPSC-derived cardiomyocytes (Cor.4U) on an automated planar patch clamp set-up (QPatch)

Human induced pluripotent stem cell-derived cardiomyocytes
(hiPSC – CM) are providing new, highly predictive strategies to assess cardiotoxicity in vitro and can thus reduce costs for cardiac safety assessment in drug development (Ma et al., 2011).
In the present study, we characterized Cor.4U® cells using Sophion’s 48-channel QPatch both in voltage and in current clamp mode.

Electrophysiological investigation of hiPSC-CM requires a high quality set up that offers the possibility to both record action potentials in current clamp mode and to isolate individual ion channel currents using voltage clamp.

The QPatch fulfills these requirements and does not rely on the use of a seal enhancer. Many automated patch clamp systems rely on the use of fluoride in the internal solution to gain sufficiently high seal resistances. However, fluoride is also known to chelate Ca²⁺, inhibit proteases and hyperpolarize the gating of sodium channels and may thus affect the recordings (Cummins et al., 2009).

As the number of cardiomyocytes are usually limited, it is critical to minimize the cell consumption per experiment. QPatch is endowed with a feature that helps to reduce the number of cells needed per experiment. Using this feature, 200 μl of cell suspension is sufficient to run a 48-well QPlate.